For the track enthusiasts and racers in the comments section - This is basically how we set up modern FWD touring cars. Especially in classes where you aren't allowed to run massive front tyres relative to the rears.
I understand that fwd British touring cars (like other series around the world) are very tricky to drive, but thrive on their inherent instability - but only if you know what you're doing!
When I had a Peugeot 205 Gti many years ago, the lift off oversteer was not very benign, and of course there were no fancy electronics to save the day. But in other fwd cars, it's very enjoyable when you get it right. My Mk2 Golf GTI 16V would lift a rear wheel, which was surprising, but that handled very well.
It's not great if you aren't expecting it. I suspect it was a contributing factor when I spun my FWD land barge on the interstate in mixed rain/snow conditions.
Great video. Everything you outline here is dead-on correct. Another factor people dont think about is that typically fwd cars are lighter than rwd and awd cars. That is always a good thing.
Understanding the friction circle made me a significantly better driver. Thanks for all your education over the decades, so glad you're putting it into books again. Yeah the lift off oversteer, something to be wary of in cars with the fuel tank right near the back.
2005 Ford Focus Wagon owner here. Simply fitting a significantly larger/stiffer rear swaybar with poly bushings and upgraded end links with poly bushings completely changed the way my car handled. At the same time I did that I replaced all the springs and shocks so they're back to factory levels of performance. Now the car tucks into corners eagerly and with ease. If I'm pushing it hard and liftoff with a dab of brakes I can induce a slide. Without brakes it rotates and tucks in. Handles completely different and better. Very neutral at the limit with almost no understeer now. That's on regular all seasons 185s all the way around. This guy is right and you don't have to go crazy to make your car handle and feel better to drive.
People think that worn out shock absorbers just start clunking and maybe ride a bit softer. No-no. I bought my car from some girl who never did maintenance on it. It was driving terribly, it was a workout to keep car going straight at 90kmh. It was swaying and leaning to every direction. Felt like the car is floating on giant cushion of air. I fitted new regular-use Monroe shocks and some sports springs. The difference is unbelivable. Car goes straight like an arrow, i can drive hands-free at 130kmh without any issues. So friends, before you start modifying - make sure your car's suspension is in good condition.
You'll often hear people say FWD is "wrong wheel drive" but in gravel rally events they outpace RWD cars. It's viewed as an achievement when someone wins a 2WD class in a RWD.
Spot on Julian, and props for mentioning the importance of castor on fwd. Rules permitting, most - if not all -fwd racing cars have ludicrous amounts of degrees positive castor (+10, or higher), while the road going cars on which they are loosely based tend to be in the+3 to +5 range. Always important to watch the impact on bump steer when adding castor as it will change the position of the tie rod relative to the lower ball joint. Sometimes can work in your favour, others times works against you a bit. In all, it really does help optimize the tire in braking and in cornering.
THANK YOU! Im installing a slightly stiffer rear swaybar and balljoints that add negative camber and fix the roll center on my GTI. Im looking forward to your book. 👍
Hi Julian, well presented mate. I stumbled across your channel by accident, haven't heard from you in years. Didn't know you were still writing. I'm the crazy fella that bought your Camira, Nissan EXA and C210 Skyline. That camira used to put a huge smile on my face. Steering that thing was with the use of ya right foot. Loved it. I agree front wheel drive is much better for a road car. Cheers
Good to hear from you. And I've done lots of writing since then! www.amazon.com.au/stores/Julian-Edgar/author/B00C3MRYN4/allbooks?ref=ap_rdr&isDramIntegrated=true&shoppingPortalEnabled=true
Wow mate you have been busy. Seems like a life time ago that I purchased 21st century performance. I'll grab a copy of your new book. I'm having issues with my race car handling. TS Astra SRi. Have put I whiteline swaybar on the rear and firmer springs. The issue I'm experiencing is the car has all the grip in the world until it doesn't, then it will spin on a dim and there's no way of catching it. Not sure if I'm over driving it or there's an issue.
Interesting, the sway bar is set to it's hardest point. I can back it off and see what happens. Aero is another interesting point as it's a dirt circuit car. No windows, interior etc, otherwise the vehicle looks standard from the outside.
@@TheJlmac one weird possibility with your inconsistent grip which I've encountered in a dirt application: at times, on damp clay sections my wheel speeds weren't high enough to self-clear the treads. see if you can reliably induce it and get some video from an observer.
Can’t wait for the book! He recommended to make the rear work more. I used polyurethane bushings on the end link of the rear sway bars and it is a great feeling during fast corners. New “stock” shocks and the result is still obvious. Just awesome tips indeed!
There are a lot of fwd compact pickups here in Brazil and they handle as you describe because the rear suspensions are harder than the hatchbacks they're based on, for more cargo load capacity. When empty, they have a good amount of oversteer.
I love your explanations. I’ve been playing around with front wheel drives for years and totally concur with your recommendations. This will make you smile, I learned to drive in my Dads Austin 1800. You’ve mentioned you had one also. One thing to mention, If you’re being a bit of a lad in the wet and you have lift off oversteer. Sometime the oversteer can start to get out of hand. Total lift off just makes it worse but that’s the natural reaction. Lift off with a little engine braking is a bit of a nightmare. Having the balls to apply a bit of throttle in those situations is easier said than done. 😂
YES. I had a Ford Laser KE Ghia (Australia...elsewhere Mazda 323) where I fitted a standard Laser rear anti-roll bar (Kind of fully floating cheap modification) underneath the Ghia's; which itself used a slightly bigger rear anti-roll bar from stock. It was weird; One expects the the rear to be stiffer , but the car just sat down on the outside rear wheel and steered itself into corners. So controllable, so accurate, and it surprised many modern vehicles. Possibly at very high speeds ( or loads) it was a tad too much, but it was a bog standard Laser engine and never gave me cause to be concerned. Cheers.
I have a Pontiac G6 and it plows in hard cornering. I replaced the original tires (225/50-R17) with 245/45-R17 on wider rims. It now has more grip but still plows at the limit. I'm going to try your advice (stiffening rear suspension). The GT model has stiffer springs and sway bar and I can get the parts cheap at any salvage yard.
My peugeot 306 Gti6 had the balance you described. Fantastic to drive in 99% of the time. Spun it once when I came into a corner too fast and took foot off the accelerator... tail came around real fast. I also had a Holden Astra SRI 2.2 that standard had surefooted if bland handling. Upgraded to koni yellows and upped the rebound in the rear. This definitely reduced turnin understeer. Much nicer cornering. That car was great on rough country roads. Soaked up the bumps and potholes. I would recommend adjustable dampers if the existing dampers need replacing.
Julian, I’ve watched every one of your videos, and I love how clear you make every topic. For the front wheel drive cornering would it be potentially more comfortable and safer in wet weather to first remove some roll stiffness from the front before adding to the rear? I got the idea that we want to use the minimum amount of stiffness needed to do the job. Thank you.
Great explanation sir. I recently overhauled the entire suspension on my K swapped EG civic hatchback. I am using 10kg rate front and 5kg rate on the rear with hardened rubber bushings all around, fresh balljoints. The car is fitted with an OEM 22mm front sway bar and have recently installed a 24mm rear sway bar and chassis brace currently set on its stiffest setting (it has 2 settings "soft" and "stiff"). Camber wise I have -2 all around and sitting on 195/50/15 Hankooks. Only been driving for about a week since finishing and have had a track day and found the rear loved to step out. Your video shows that the car is doing what is needed to be faster, I just need to learn how to drive it and take advantage of the lift off oversteer. (I spun once and slipped out a few times.)
Doing something similar to you with a 2000 ek hatch and have the same issue. From what Julian is implying, maybe a softer rear sway bar might help make it less twitchy/oversteering in the rear. I have the progress 22mm bar in the front and same 22mm in the rear with 8kg front springs and 5kg rears with urethane bushings all the way around. wishing I had got a smaller rear sway bar after hearing Julian speak and driving my car confirmed what he says. It will come around easier than I prefer when pushed. it's also very hard riding on the road, more than I like to be honest. 90%road-10%track car
Timely! Although I think I might have swung the balance a little too far now. I have a reasonably front-heavy turbo FTO, which I finally had the ride height raised to correct the roll centre, but now it has got more positive rake than it did factory. Barely any understeer to speak of, but if I come in hot on the brakes, especially into lower speed corners, the rear wants to come around very quickly. But I've changed so much now it's hard to remember what the factory characteristics were like 😅 I'm thinking I may bring the rear down to level the chassis, and maybe add a smidge more rear camber. Beyond that the rear bar is on the middle setting, and I haven't mucked about with the damper stiffness yet either. I like how responsive the handling is, but I'd rather not loop it unexpectedly (again!).
Very interesting video! FWD cars are lighter and have less drivetrain losses, so higher WHP for a given crank HP. I think any car with less than 200hp should be FWD as they can handle this sort of power without issue. The problem (for me) with setting my FWD car up to have a lift-off oversteer bias is that my car tends to snap-oversteer at a certain point, which I need to compensate for with driving style (by being more ginger on entry). I have plenty of grip on the front at turn-in, with slight trail braking to mid-corner. By mid-corner with c. 10%-25% throttle I can feel the rear rotating. Everything is fine on exit once I don't absolutely floor it. In the wet, the driving style needs to be toned down by 50%. On back roads when searching for the limit (in as safe a manner as possible), all four wheels will slide on long corners. My thoughts are that this implies a good balance. My car is as unsporty as they get: 2001 VW Passat, FWD, 1.9 TDI, c. 210hp, open diff, solid rear axle with Eibach Pro-kit lowering springs and Bilstein B4 (sport) dampers, same front springs and Bilstein B8 trackday dampers, Goodyear Asymmetric 6 tyres. Everything is fairly new and well maintained.
I'm very excited for this book to come out. Your videos have been able to explain things to me that countless other videos I've watched could not make stick. A quick question if you have the time, would decreasing the amount of negative camber in the rear of the car (i.e. going from -2.5 to -1.0) increase the amount of liftoff oversteer? I'm trying to understand the balance of stiffness vs suspension angles. Reason for my curiosity is I've got a volvo C30 that has a lot of negative camber from factory, and I'm curious if the cornering could be improved by reducing it (and have more even tire wear too).
The other secret sauce is to dial out rear toe-in. The more you tend toward zero rear toe or some toe out (if you know what you are doing), the more inherent instability you put into the rear. The car will react better on turn in, it'll rear steer with less pronounced lift offs and love direction changes like chicanes. Yes it can feel hairy through high speed sweepers but the way to temper that is not to add rear toe out without also adding rear neg camber. The rear neg cambers influence is that at high speed the rear toe out you've added has its ugly side negated, yet you'll get all the benefits in the slow speed stuff.
Hello, I wanted to ask a few questions to you if you wouldn't mind: 1. Do you think tire pressure can alter the oversteer-understeer characteristics of a car? Instead of altering my anti-roll bars and other suspension elements, I tend to overinflate my rear tires just a bit to get less understeering around corners and change the yaw more effectively through lift-off oversteering. However, I am not sure how wise it is to do so, as the wear on the tires could be less even on the rear (Factory says 33 psi front, 32 rear. I do 33 psi front, and 34 rear) 2. What is your take on left foot breaking to get the car to oversteer around corners for rotating the car more effectively. I know modern cars don't allow you to throttle while breaking, is there still a use for the technique in modern cars? 3. Won't changing the suspension component affect the stability control of the car and cause problems in handling? 4. Have you ever used a test like the moose test to evaluate handling? Or do you find such tests to be unimportant in what they measure.
1. Minor tyre pressure changes are fine. 2. You can use left foot braking if you want. 3. Stability control intervenes only when traction (longitudinal or lateral) has been lost. 4. Yes, a swerve and recover is an excellent test of vehicle handling, control and stability.
Julian! Lovely video, great as always! Are you going to be talking about road/track effectiveness of front and back top strut and underfloor suspension braces?
@@JulianEdgar I'm looking more from a modification of simple suspension systems, think suzuki alto. More flexible, older cars with suspension setups designed around compact, cheap engineering. If it's not your jam and nothing of interest to you that's cool!
The other thing with the rear sway bar is stiffer end links. I've just done this with my Mk1 Focus with good results. The factory mushy rubber wasn't doing anything any favours.
I have an Mk1 Focus and have owned another previously. A stiffer rear bar with no change to the front along with upgraded rear end links completely changed the car.
Saab cars are set up this way from factory(your ideal fwd car). Or at least the ones I have driven. 9-5, old and new 9-3. The old 9-3 especially. The newer version has more static oversteer than the old one. Quite fun to drive. But they are all too soft for repeated quick changes in direction.
I know many of your recent videos have been a bit more road car focussed but I’m really interested from a track car point of view. What has really interested me in this video is the part at the end where you talk about weight in the rear. I’m currently building a Toyota Yaris 1.0 litre turbo sprint car and as I’m on track for no more than 70 seconds I’m doing an ice box charge cooler setup. I can fit this under the bonnet or in the boot (trunk) and of course with 20ltrs or so of water in it then it can affect the weight distribution in a car that will likely be less than 800kgs. You are suggesting that if I put it in the boot it might make lift off oversteer worse but how will it affect grip if I put it in the engine bay? More weight over the front wheels good?
Make the f/r weight distribution as even as possible. It’s the *change* in weight distribution in a road car (eg 200kg extra in the back) which is the issue.
Yep, sounds like a recipe for liftoff oversteer. Discovered that when I had bad front shocks, new rear ones, and spun. Sure, the driver was not great at all lol
I know it isn't directly related to the content of THIS video, but, in your opinion, what's the maximum practical FWD power-to-weight ratio for the street? 200hp per ton? 300? Certainly not 400hp per ton or more, though... Aside from that, on a more related note, if someone were to tune a FWD car to have slight power understeer and to lift off neutral (and perhaps trail-braking oversteer) with just the driver, would that be likely to end up giving it the balanced lift off oversteer you described when fully loaded?
I don't have a particular opinion on max power to weight on a FWD - depends on a whole range of things eg flatness of torque curve, ability of traction control, etc. NO - getting the car handling as I have described WILL NOT give the same results when fully loaded. Always test loaded.
There are a lot of variables that can affect how much power a car can safely handle. So there's no easy answer. But if you become familiar with a certain type of car, you might get a feel for it. It would help to join a car club, and ride in other people's cars with different power levels.
@@JulianEdgar That's not what I asked. I already understand it won't be the same loaded vs unloaded. What I asked was, if you tuned it to be lift-off neutral with only the driver, would it have, as a rule of thumb given the average delta between fully loaded and minimally loaded, close to the ideal amount of lift-off oversteer while loaded without having too much?
Do you have adjustable dampers already? It could be worth seeing to getting something with adjustable dampers though I think Tein and Koni make adjustable dampers that can use the stock springs for you to play with for that car
Lugs/studs don't hold shear loads, so adding spacers (assuming long enough studs for sufficient thread engagement) cannot possibly change anything from the stud or lug's perspective. As for scrub radius, sure, but worth noting that the scrub radius built into any OEM vehicle is going to be way too aggressive for actual track steering angles because they are set for much sharper corners than you'll find on any track. For autocross, sure, the scrub radius challenge matters because autocross corner radii mimic street radii. But even then you won't see champion cars in classes where track width can be altered who haven't increased their front track width dramatically, even if simply to use wider wheels/tires. From a geometry perspective, there is no difference between spacers versus wheels with lower offsets than stock. That's literally what a wheel with a lower offset is: a wheel with a "spacer" formed into it. And people run wheels with lower offsets all the time. Yes, you increase leveraged load on the knuckle/hub/bearing when sitting still or going straight, and you increase load on the inside knuckle/hub/bearing during corning. But you actually decrease the leveraged load on the outside knuckle during cornering, and the high-load outside parts are the ones at most risk of failure during cornering. So you are actually reducing load from the most stressed parts. But be warned that increasing front track width shifts loads to the FRONT, not the rear. All else being equal, it only increases understeer. And of course, please never run the spacers that have secondary built-in lugs made out of wet noodles. Solid billet blocks and extended high strength studs (or just wheels with the desired offset to start with) are the way to do this right.
In some cars the wheel studs hold shear loads. Yes people often badly change scrub radius by altering offset - not sure how one poor mod justifies another? There’s a reason wheel spacers for road cars are illegal in most jurisdictions.
@@JulianEdgar So, I suppose that 1.5 degrees wouldn’t wear the tires much more than 1 degree? I currently have 1 degree, and I am asking because I want something more aggressive without destroying the tires like 2 degrees probably would. My current tires are Goodyear Supersport, which have a stiffer sidewalls than a normal tire would. Thank you very much, and I would definitely buy your book in August!
@@JulianEdgar i see thanks for the answer. But one thing i still cant grasp my head around is why exactly the stiffer bar causes more load to be transferred to the outside tyre 🙂
I have only FWD and RWD cars and I can using drivetrain to steering the car. I think that on the road the worse are AWD cars because there is no control which wheel is driven. In most of road cars there is LSD dyferential only on the midle and it ussualy dosnt work well. I hate QUATTRO on snow because i can't drive fast in the corners. I never know what drivetrain will do and sometimes i have oversteer sometimes understeer. In RWD I can let go the gas to put small rezistance on the rear to stabilize the car. And I have full controil on the forces on the car body. Similiar, but opossit in FWD. But in AWD I have no control and i dont like it. One axle drive with good tires and smart geometry setup is the best option.
Much too general a comment. Some AWD cars can be driven like RWD cars, others can be driven like FWD cars, and still other AWD cars have driver- selectable modes. A constant AWD Audi is best set up and driven a bit like a FWD ie using the techniques in this video.
@@JulianEdgar Yes, they are not all the same, but in civilian AWD the differentials are too open. Torsen tends to open under low resistance, so QUATTRO does not break grip and wheel speeds remain varied, which makes it difficult to tighten corners and increases understeer. In my opinion, this is dangerous when driving fast on snow because the heavily understeered drive becomes oversteered in some situations. When engine braking, I am never sure whether the car will generate drag from the front or rear. The BMW has a more closed differential between the axles, so it is more aggressive but gives more control to the driver. Nevertheless, in civilian AWD I have no control over generating force on only one axle, which is very useful in directing the force that stabilizes or destabilizes the body. In winter, many drivers drive very slowly, and in AWD car I have a problem with changing lanes when overtaking them. Sometimes the drive is generated from the rear, sometimes from the front and that without my control, which is dangerous. In a FWD/RWD car I can use the brake and gas pedal to generate forces in any direction. In my RWD I have the LSD differential set to 70Nm so it is closed on ice and car wants to go straight, I have a very large caster and large camber at the front but I have it compensated by the toe-in so the car is stable. I also have a neutral bumpsteer. When I let off the gas the car becomes very understeer and super stable. In my FWD it works a bit differently, but the driven axle can also be used to control the force on the body. But in an AWD car, releasing the gas pedal sometimes causes resistance on one of the front wheels, which deepens the slide when driving on snow. And I'm never sure what the car's drivetrain will do. In rally cars, AWD is completely different, with precisely set locks on each differential. LSD on the front is much weaker, also middle diferential can be set what ever driver want to get. This gives you full control over the forces acting on the body. In civilian AWD, zero control on it. Thats why i have only FWD / RWD cars. Normal AWD looks pointless for me.
For the average Joe RWD is dead anyway, especially for a track vehicle. Unless its a Miata or BMW 3 series and neither or those will be as affordable to run as a Civic. I've come to absolutely adore FWD over the years and I was an absolute stallwart of RWD and have owned some very nice cars with that setup. Currently have AWD though 😂 best of both worlds.
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For the track enthusiasts and racers in the comments section - This is basically how we set up modern FWD touring cars. Especially in classes where you aren't allowed to run massive front tyres relative to the rears.
I understand that fwd British touring cars (like other series around the world) are very tricky to drive, but thrive on their inherent instability - but only if you know what you're doing!
liftoff oversteer is a great feeling when you get it right. saved me from a couple shunts in the past
When I had a Peugeot 205 Gti many years ago, the lift off oversteer was not very benign, and of course there were no fancy electronics to save the day. But in other fwd cars, it's very enjoyable when you get it right.
My Mk2 Golf GTI 16V would lift a rear wheel, which was surprising, but that handled very well.
It's not great if you aren't expecting it. I suspect it was a contributing factor when I spun my FWD land barge on the interstate in mixed rain/snow conditions.
Great video. Everything you outline here is dead-on correct. Another factor people dont think about is that typically fwd cars are lighter than rwd and awd cars. That is always a good thing.
Which FWD is lighter than the RWD MX5?
@@angry9901 I own a ford festiva and those weigh around 1700 pounds
@@angry9901 some old civics and honda fit ?
@@NO.TE.2024 old civics from 90-99 are around 2300-2500 pounds
Understanding the friction circle made me a significantly better driver. Thanks for all your education over the decades, so glad you're putting it into books again. Yeah the lift off oversteer, something to be wary of in cars with the fuel tank right near the back.
Oh wow, I didn't even think about sloshing a fuel in this scenario.
@@roflchopter11 it will bite your ass SO FAST its no joke
2005 Ford Focus Wagon owner here. Simply fitting a significantly larger/stiffer rear swaybar with poly bushings and upgraded end links with poly bushings completely changed the way my car handled. At the same time I did that I replaced all the springs and shocks so they're back to factory levels of performance. Now the car tucks into corners eagerly and with ease. If I'm pushing it hard and liftoff with a dab of brakes I can induce a slide. Without brakes it rotates and tucks in. Handles completely different and better. Very neutral at the limit with almost no understeer now. That's on regular all seasons 185s all the way around. This guy is right and you don't have to go crazy to make your car handle and feel better to drive.
People think that worn out shock absorbers just start clunking and maybe ride a bit softer. No-no. I bought my car from some girl who never did maintenance on it. It was driving terribly, it was a workout to keep car going straight at 90kmh. It was swaying and leaning to every direction. Felt like the car is floating on giant cushion of air. I fitted new regular-use Monroe shocks and some sports springs. The difference is unbelivable. Car goes straight like an arrow, i can drive hands-free at 130kmh without any issues. So friends, before you start modifying - make sure your car's suspension is in good condition.
Excellent concept: steering with the right foot.
You'll often hear people say FWD is "wrong wheel drive" but in gravel rally events they outpace RWD cars. It's viewed as an achievement when someone wins a 2WD class in a RWD.
Spot on Julian, and props for mentioning the importance of castor on fwd. Rules permitting, most - if not all -fwd racing cars have ludicrous amounts of degrees positive castor (+10, or higher), while the road going cars on which they are loosely based tend to be in the+3 to +5 range. Always important to watch the impact on bump steer when adding castor as it will change the position of the tie rod relative to the lower ball joint. Sometimes can work in your favour, others times works against you a bit. In all, it really does help optimize the tire in braking and in cornering.
THANK YOU! Im installing a slightly stiffer rear swaybar and balljoints that add negative camber and fix the roll center on my GTI. Im looking forward to your book. 👍
Hi Julian, well presented mate. I stumbled across your channel by accident, haven't heard from you in years. Didn't know you were still writing. I'm the crazy fella that bought your Camira, Nissan EXA and C210 Skyline. That camira used to put a huge smile on my face. Steering that thing was with the use of ya right foot. Loved it.
I agree front wheel drive is much better for a road car. Cheers
Good to hear from you. And I've done lots of writing since then! www.amazon.com.au/stores/Julian-Edgar/author/B00C3MRYN4/allbooks?ref=ap_rdr&isDramIntegrated=true&shoppingPortalEnabled=true
Wow mate you have been busy. Seems like a life time ago that I purchased 21st century performance.
I'll grab a copy of your new book.
I'm having issues with my race car handling. TS Astra SRi. Have put I whiteline swaybar on the rear and firmer springs. The issue I'm experiencing is the car has all the grip in the world until it doesn't, then it will spin on a dim and there's no way of catching it. Not sure if I'm over driving it or there's an issue.
Sounds too stiff in roll overall. (Or if it occurs only at high speed, aero lift.)
Interesting, the sway bar is set to it's hardest point. I can back it off and see what happens. Aero is another interesting point as it's a dirt circuit car.
No windows, interior etc, otherwise the vehicle looks standard from the outside.
@@TheJlmac one weird possibility with your inconsistent grip which I've encountered in a dirt application: at times, on damp clay sections my wheel speeds weren't high enough to self-clear the treads. see if you can reliably induce it and get some video from an observer.
Can’t wait for the book!
He recommended to make the rear work more. I used polyurethane bushings on the end link of the rear sway bars and it is a great feeling during fast corners.
New “stock” shocks and the result is still obvious.
Just awesome tips indeed!
There are a lot of fwd compact pickups here in Brazil and they handle as you describe because the rear suspensions are harder than the hatchbacks they're based on, for more cargo load capacity. When empty, they have a good amount of oversteer.
Thank you for the disclaimer at the end for when you have extra load on the rear tires
Awesome video... Things like tire pressure, weight distribution and torque curves all mentioned in the book as well.
I love your explanations. I’ve been playing around with front wheel drives for years and totally concur with your recommendations. This will make you smile, I learned to drive in my Dads Austin 1800. You’ve mentioned you had one also.
One thing to mention, If you’re being a bit of a lad in the wet and you have lift off oversteer. Sometime the oversteer can start to get out of hand. Total lift off just makes it worse but that’s the natural reaction. Lift off with a little engine braking is a bit of a nightmare. Having the balls to apply a bit of throttle in those situations is easier said than done. 😂
Thank you Mr.Edgar🤓👍🏽
Excellent, as always. Thanks for this one
Thank you.
YES. I had a Ford Laser KE Ghia (Australia...elsewhere Mazda 323) where I fitted a standard Laser rear anti-roll bar (Kind of fully floating cheap modification) underneath the Ghia's; which itself used a slightly bigger rear anti-roll bar from stock. It was weird; One expects the the rear to be stiffer , but the car just sat down on the outside rear wheel and steered itself into corners. So controllable, so accurate, and it surprised many modern vehicles. Possibly at very high speeds ( or loads) it was a tad too much, but it was a bog standard Laser engine and never gave me cause to be concerned. Cheers.
I have a Pontiac G6 and it plows in hard cornering. I replaced the original tires (225/50-R17) with 245/45-R17 on wider rims. It now has more grip but still plows at the limit. I'm going to try your advice (stiffening rear suspension). The GT model has stiffer springs and sway bar and I can get the parts cheap at any salvage yard.
I eagerly await the book! Your aerodynamics series has helped thousands of people and certainly your work will help many many thousands more.
Thank you.
My peugeot 306 Gti6 had the balance you described. Fantastic to drive in 99% of the time. Spun it once when I came into a corner too fast and took foot off the accelerator... tail came around real fast.
I also had a Holden Astra SRI 2.2 that standard had surefooted if bland handling.
Upgraded to koni yellows and upped the rebound in the rear.
This definitely reduced turnin understeer. Much nicer cornering.
That car was great on rough country roads. Soaked up the bumps and potholes.
I would recommend adjustable dampers if the existing dampers need replacing.
Thanks!
Thank you
Julian, I’ve watched every one of your videos, and I love how clear you make every topic. For the front wheel drive cornering would it be potentially more comfortable and safer in wet weather to first remove some roll stiffness from the front before adding to the rear? I got the idea that we want to use the minimum amount of stiffness needed to do the job.
Thank you.
Yes you could do that - depends how stiff the car is in roll in the first place.
Dear Julian, may God bless. I thoroughly enjoy you video's. What a fantastic teacher.
Thank you. (But you should see my books!)
Great explanation sir. I recently overhauled the entire suspension on my K swapped EG civic hatchback. I am using 10kg rate front and 5kg rate on the rear with hardened rubber bushings all around, fresh balljoints. The car is fitted with an OEM 22mm front sway bar and have recently installed a 24mm rear sway bar and chassis brace currently set on its stiffest setting (it has 2 settings "soft" and "stiff"). Camber wise I have -2 all around and sitting on 195/50/15 Hankooks. Only been driving for about a week since finishing and have had a track day and found the rear loved to step out. Your video shows that the car is doing what is needed to be faster, I just need to learn how to drive it and take advantage of the lift off oversteer. (I spun once and slipped out a few times.)
Damn, 24mm sway bar in the rear sounds race spec!
Doing something similar to you with a 2000 ek hatch and have the same issue. From what Julian is implying, maybe a softer rear sway bar might help make it less twitchy/oversteering in the rear. I have the progress 22mm bar in the front and same 22mm in the rear with 8kg front springs and 5kg rears with urethane bushings all the way around. wishing I had got a smaller rear sway bar after hearing Julian speak and driving my car confirmed what he says. It will come around easier than I prefer when pushed. it's also very hard riding on the road, more than I like to be honest. 90%road-10%track car
Timely! Although I think I might have swung the balance a little too far now. I have a reasonably front-heavy turbo FTO, which I finally had the ride height raised to correct the roll centre, but now it has got more positive rake than it did factory. Barely any understeer to speak of, but if I come in hot on the brakes, especially into lower speed corners, the rear wants to come around very quickly. But I've changed so much now it's hard to remember what the factory characteristics were like 😅
I'm thinking I may bring the rear down to level the chassis, and maybe add a smidge more rear camber. Beyond that the rear bar is on the middle setting, and I haven't mucked about with the damper stiffness yet either. I like how responsive the handling is, but I'd rather not loop it unexpectedly (again!).
Very interesting video! FWD cars are lighter and have less drivetrain losses, so higher WHP for a given crank HP. I think any car with less than 200hp should be FWD as they can handle this sort of power without issue.
The problem (for me) with setting my FWD car up to have a lift-off oversteer bias is that my car tends to snap-oversteer at a certain point, which I need to compensate for with driving style (by being more ginger on entry). I have plenty of grip on the front at turn-in, with slight trail braking to mid-corner. By mid-corner with c. 10%-25% throttle I can feel the rear rotating. Everything is fine on exit once I don't absolutely floor it. In the wet, the driving style needs to be toned down by 50%.
On back roads when searching for the limit (in as safe a manner as possible), all four wheels will slide on long corners. My thoughts are that this implies a good balance.
My car is as unsporty as they get: 2001 VW Passat, FWD, 1.9 TDI, c. 210hp, open diff, solid rear axle with Eibach Pro-kit lowering springs and Bilstein B4 (sport) dampers, same front springs and Bilstein B8 trackday dampers, Goodyear Asymmetric 6 tyres. Everything is fairly new and well maintained.
I'm very excited for this book to come out. Your videos have been able to explain things to me that countless other videos I've watched could not make stick.
A quick question if you have the time, would decreasing the amount of negative camber in the rear of the car (i.e. going from -2.5 to -1.0) increase the amount of liftoff oversteer? I'm trying to understand the balance of stiffness vs suspension angles.
Reason for my curiosity is I've got a volvo C30 that has a lot of negative camber from factory, and I'm curious if the cornering could be improved by reducing it (and have more even tire wear too).
It will make a small difference.
Your ideal handling reminds me of how ayrton senna driving style even though he drove rear wheel cars.
thank u sir , very informative ❤️
Thank you.
The other secret sauce is to dial out rear toe-in. The more you tend toward zero rear toe or some toe out (if you know what you are doing), the more inherent instability you put into the rear. The car will react better on turn in, it'll rear steer with less pronounced lift offs and love direction changes like chicanes. Yes it can feel hairy through high speed sweepers but the way to temper that is not to add rear toe out without also adding rear neg camber. The rear neg cambers influence is that at high speed the rear toe out you've added has its ugly side negated, yet you'll get all the benefits in the slow speed stuff.
Hello,
I wanted to ask a few questions to you if you wouldn't mind:
1. Do you think tire pressure can alter the oversteer-understeer characteristics of a car? Instead of altering my anti-roll bars and other suspension elements, I tend to overinflate my rear tires just a bit to get less understeering around corners and change the yaw more effectively through lift-off oversteering. However, I am not sure how wise it is to do so, as the wear on the tires could be less even on the rear (Factory says 33 psi front, 32 rear. I do 33 psi front, and 34 rear)
2. What is your take on left foot breaking to get the car to oversteer around corners for rotating the car more effectively. I know modern cars don't allow you to throttle while breaking, is there still a use for the technique in modern cars?
3. Won't changing the suspension component affect the stability control of the car and cause problems in handling?
4. Have you ever used a test like the moose test to evaluate handling? Or do you find such tests to be unimportant in what they measure.
1. Minor tyre pressure changes are fine.
2. You can use left foot braking if you want.
3. Stability control intervenes only when traction (longitudinal or lateral) has been lost.
4. Yes, a swerve and recover is an excellent test of vehicle handling, control and stability.
Julian! Lovely video, great as always! Are you going to be talking about road/track effectiveness of front and back top strut and underfloor suspension braces?
On any modern car braces do very little. Spend your money on stuff that makes dramatic differences.
@@JulianEdgar I'm looking more from a modification of simple suspension systems, think suzuki alto. More flexible, older cars with suspension setups designed around compact, cheap engineering. If it's not your jam and nothing of interest to you that's cool!
Same comment. Do everything else first.
The other thing with the rear sway bar is stiffer end links. I've just done this with my Mk1 Focus with good results. The factory mushy rubber wasn't doing anything any favours.
I have an Mk1 Focus and have owned another previously. A stiffer rear bar with no change to the front along with upgraded rear end links completely changed the car.
Saab cars are set up this way from factory(your ideal fwd car). Or at least the ones I have driven. 9-5, old and new 9-3. The old 9-3 especially. The newer version has more static oversteer than the old one. Quite fun to drive. But they are all too soft for repeated quick changes in direction.
A good example of where leaving everything alone but for fitting stiffer dampers (shocks) is likely to give good results.
wonderful stuff!! ... sooooo most if these Principles apply to everday drivers... not just high performance cars? thank you for a response.
The principles apply to all cars.
I know many of your recent videos have been a bit more road car focussed but I’m really interested from a track car point of view. What has really interested me in this video is the part at the end where you talk about weight in the rear. I’m currently building a Toyota Yaris 1.0 litre turbo sprint car and as I’m on track for no more than 70 seconds I’m doing an ice box charge cooler setup. I can fit this under the bonnet or in the boot (trunk) and of course with 20ltrs or so of water in it then it can affect the weight distribution in a car that will likely be less than 800kgs. You are suggesting that if I put it in the boot it might make lift off oversteer worse but how will it affect grip if I put it in the engine bay? More weight over the front wheels good?
Make the f/r weight distribution as even as possible. It’s the *change* in weight distribution in a road car (eg 200kg extra in the back) which is the issue.
@@JulianEdgar ok thanks. I was worried that the weight in the boot would create a sort of pendulum effect.
Yep, sounds like a recipe for liftoff oversteer. Discovered that when I had bad front shocks, new rear ones, and spun.
Sure, the driver was not great at all lol
I know it isn't directly related to the content of THIS video, but, in your opinion, what's the maximum practical FWD power-to-weight ratio for the street? 200hp per ton? 300? Certainly not 400hp per ton or more, though... Aside from that, on a more related note, if someone were to tune a FWD car to have slight power understeer and to lift off neutral (and perhaps trail-braking oversteer) with just the driver, would that be likely to end up giving it the balanced lift off oversteer you described when fully loaded?
I don't have a particular opinion on max power to weight on a FWD - depends on a whole range of things eg flatness of torque curve, ability of traction control, etc. NO - getting the car handling as I have described WILL NOT give the same results when fully loaded. Always test loaded.
There are a lot of variables that can affect how much power a car can safely handle. So there's no easy answer. But if you become familiar with a certain type of car, you might get a feel for it. It would help to join a car club, and ride in other people's cars with different power levels.
@@JulianEdgar That's not what I asked. I already understand it won't be the same loaded vs unloaded. What I asked was, if you tuned it to be lift-off neutral with only the driver, would it have, as a rule of thumb given the average delta between fully loaded and minimally loaded, close to the ideal amount of lift-off oversteer while loaded without having too much?
I have a mr2 spyder. Car haddles pretty good already. Except in the wet. The cars ride is too stiff for back roads. How can i make it softer?
Do you have adjustable dampers already? It could be worth seeing to getting something with adjustable dampers though I think Tein and Koni make adjustable dampers that can use the stock springs for you to play with for that car
Hi Julian
What about fitting wheel spacers in the front ? Is it recommended ?
No. Changes stud (lug) loads and steering scrub radius.
Messing up the scrub radius makes the steering feel like you're trying to put an angry cat in a bath.
Lugs/studs don't hold shear loads, so adding spacers (assuming long enough studs for sufficient thread engagement) cannot possibly change anything from the stud or lug's perspective. As for scrub radius, sure, but worth noting that the scrub radius built into any OEM vehicle is going to be way too aggressive for actual track steering angles because they are set for much sharper corners than you'll find on any track. For autocross, sure, the scrub radius challenge matters because autocross corner radii mimic street radii. But even then you won't see champion cars in classes where track width can be altered who haven't increased their front track width dramatically, even if simply to use wider wheels/tires.
From a geometry perspective, there is no difference between spacers versus wheels with lower offsets than stock. That's literally what a wheel with a lower offset is: a wheel with a "spacer" formed into it. And people run wheels with lower offsets all the time. Yes, you increase leveraged load on the knuckle/hub/bearing when sitting still or going straight, and you increase load on the inside knuckle/hub/bearing during corning. But you actually decrease the leveraged load on the outside knuckle during cornering, and the high-load outside parts are the ones at most risk of failure during cornering. So you are actually reducing load from the most stressed parts.
But be warned that increasing front track width shifts loads to the FRONT, not the rear. All else being equal, it only increases understeer.
And of course, please never run the spacers that have secondary built-in lugs made out of wet noodles. Solid billet blocks and extended high strength studs (or just wheels with the desired offset to start with) are the way to do this right.
In some cars the wheel studs hold shear loads. Yes people often badly change scrub radius by altering offset - not sure how one poor mod justifies another? There’s a reason wheel spacers for road cars are illegal in most jurisdictions.
How does a sagging spring effect handling?
Less bump travel.
also wheel alignment likely won't be optimal
And unevenly sagging springs will change corner balance
could you do a aero analysis on evs vs ice
EV = typically better because they try harder? There's not a huge lot further to say. Aero is aero, irrespective of the motive power.
Iove my FWD car
How much camber can a road car handle? Is 1-1.5 degrees suitable?
Yes
@@JulianEdgar So, I suppose that 1.5 degrees wouldn’t wear the tires much more than 1 degree? I currently have 1 degree, and I am asking because I want something more aggressive without destroying the tires like 2 degrees probably would. My current tires are Goodyear Supersport, which have a stiffer sidewalls than a normal tire would. Thank you very much, and I would definitely buy your book in August!
Why does stiffer roll bar increase load transfer? It limits roll so shouldnt it also limit load transfer instead of increasing?
Roll angle has nothing to do with load transfer.
@@JulianEdgar but rolling car will shift center of gravity so shouldnt it load the outside more compared to less rolling car?
Centre of gravity movement is nothing compared to differing front/rear lateral load transfer caused by sway bars / springs.
@@JulianEdgar i see thanks for the answer. But one thing i still cant grasp my head around is why exactly the stiffer bar causes more load to be transferred to the outside tyre 🙂
It tries to pick up the inside wheel. Therefore more load goes to the outside wheel. A full example with figures is worked through in the new book.
I have only FWD and RWD cars and I can using drivetrain to steering the car.
I think that on the road the worse are AWD cars because there is no control which wheel is driven.
In most of road cars there is LSD dyferential only on the midle and it ussualy dosnt work well.
I hate QUATTRO on snow because i can't drive fast in the corners.
I never know what drivetrain will do and sometimes i have oversteer sometimes understeer.
In RWD I can let go the gas to put small rezistance on the rear to stabilize the car.
And I have full controil on the forces on the car body.
Similiar, but opossit in FWD.
But in AWD I have no control and i dont like it.
One axle drive with good tires and smart geometry setup is the best option.
Much too general a comment. Some AWD cars can be driven like RWD cars, others can be driven like FWD cars, and still other AWD cars have driver- selectable modes. A constant AWD Audi is best set up and driven a bit like a FWD ie using the techniques in this video.
@@JulianEdgar Yes, they are not all the same, but in civilian AWD the differentials are too open.
Torsen tends to open under low resistance, so QUATTRO does not break grip and wheel speeds remain varied, which makes it difficult to tighten corners and increases understeer.
In my opinion, this is dangerous when driving fast on snow because the heavily understeered drive becomes oversteered in some situations.
When engine braking, I am never sure whether the car will generate drag from the front or rear.
The BMW has a more closed differential between the axles, so it is more aggressive but gives more control to the driver.
Nevertheless, in civilian AWD I have no control over generating force on only one axle, which is very useful in directing the force that stabilizes or destabilizes the body.
In winter, many drivers drive very slowly, and in AWD car I have a problem with changing lanes when overtaking them.
Sometimes the drive is generated from the rear, sometimes from the front and that without my control, which is dangerous.
In a FWD/RWD car I can use the brake and gas pedal to generate forces in any direction.
In my RWD I have the LSD differential set to 70Nm so it is closed on ice and car wants to go straight, I have a very large caster and large camber at the front but I have it compensated by the toe-in so the car is stable.
I also have a neutral bumpsteer.
When I let off the gas the car becomes very understeer and super stable.
In my FWD it works a bit differently, but the driven axle can also be used to control the force on the body.
But in an AWD car, releasing the gas pedal sometimes causes resistance on one of the front wheels, which deepens the slide when driving on snow.
And I'm never sure what the car's drivetrain will do.
In rally cars, AWD is completely different, with precisely set locks on each differential.
LSD on the front is much weaker, also middle diferential can be set what ever driver want to get.
This gives you full control over the forces acting on the body.
In civilian AWD, zero control on it.
Thats why i have only FWD / RWD cars.
Normal AWD looks pointless for me.
This is me
For the average Joe RWD is dead anyway, especially for a track vehicle. Unless its a Miata or BMW 3 series and neither or those will be as affordable to run as a Civic.
I've come to absolutely adore FWD over the years and I was an absolute stallwart of RWD and have owned some very nice cars with that setup.
Currently have AWD though 😂 best of both worlds.
Top trim Civics cost a lot more than an MX-5. I would never pay that much for a Civic.
@@matsudakodoalso nobody is taking a 2024 Type R on track. I'm talking used cars.