Thanks my friend, I took a long break indeed. Gathering steam to put some thoughts together in a more coherent way. I intend for this series to be a one-stop reference and guide. I hope all is well with you and your passions!
Great video. Does the short suspension travel at the front on the models you mention have something to do with the fact they are McPherson front suspension types? They typically gain camber over a short suspension travel so I would think they would like to limit the travel in order to remain in that camber gain range? Does the choice of the front suspension setup also affect the way the dampers are setup from the factory? And finally, what differences can you see on a factory damper/spring/bump stop setup with a front double wishbone suspension? Sorry if these questions are dumb, I'm just someone interested in suspension setup but I have no formal engineering education. Just a car enthusiast. Thanks!
Yes, a MacPherson strut with high motion ratio (nearly 1:1) will have less travel at the damper than an inboard-mounted double-wishbone (often 0.8:1 or lower). However, the relative wheel travel is still comparable. In the M2C video I mentioned on Farkle's channel, there was 18mm of strut travel before the bump stop starts to engage compared to 33mm at the rear. Taking into account the motion ratio, that means the front gets into the bump stops after 3/4 inch of wheel travel. That's not a lot and it's very common on most cars, especially 'sport' models. On an earlier Miata (the infamous 'R package') with double-wishbone geometry, the front bump stops were actually engaging at static ride height! The non-R models had longer springs and more clearance, but the bump stop engagement was still occurring frequently in straight-line driving and especially as soon as you begin cornering. Video here (Deep Dive on M2 suspension, part 2): ruclips.net/video/eUhJzOu3E2Q/видео.html Actually, the MacPherson geometry LOSES camber faster than it gains - you might be thinking of the double-wishbone or SLA (Short-Long Arm) which actually does gain significant camber as the suspension goes into compression. The type of suspension would affect the relative forces used since you need less overall damping on a strut vs. an inboard-mounted shock. Otherwise, the consideration is really how much weight is there and what ride frequency are you targeting. I see more force being used on a double wishbone (again, due to lower motion ratio) vs. a strut. The springs are stiffer as well. The bump stops are often similar stiffness with a similar ratio of front bump stop stiffer than rear. There are more commonalities between geometries than differences, but the differences scales with motion ratio and vehicle application. A sport coupe or sport sedan suspension will be tuned stiffer than a comfort or pure passenger application. There are videos you can watch on my channel and elsewhere to gather more information. I have another several videos coming out in this series plus the 'Qualify your Vendor' (set of 2 videos) as a way to summarize these Crucial Ride Harmony concepts into actionable questions to ask a potential suspension supplier. If you have more questions, I encourage you to save your septims and purchase a consultation session. I appreciate your interest and hope you continue to get value from this information!
@@SuspensionTruth Thank you for getting back on those questions. For the camber gain over a short amount of suspension travel, I was referring in my head to a camber change graph that I saw of a VW Golf GTI (If i remember correctly), it has a plain McPherson setup not the type used on Porsches and BMW's. I would have thought that was the reason to limit the suspension travel on a sports car application on a McPherson strut and thus using a higher spring rate via the bump stop (sorry this is speculation of course, again, no formal training) when driving hard and a softer spring rate on the spring in order to preserve some sort of comfort at normal speeds and driving. My question really is that if the reason manufacturer had to compromise on how they handle the spring rates (spring + bump stop) was in order to compensate for the front suspension design limitations for the desired application (turning a sedan into a sports car). I had an E92 M3 and I was very surprised on how little suspension travel it had. I've watched all your videos (we race an NA Miata with some friends and followed a lot of your guidelines which are great advice!) and also watched Farkle''s video which is very interesting. Thanks again!
@@fedezyl My pleasure, thanks for engaging. This is an interesting article talking about the use of bump stops, especially modern 'micro-cellular polyurethane' (MCU) which are a superior design vs. older rubber style stops (pre-2000s). www.vehicledynamicsinternational.com/features/insights-into-bump-stop-tuning.html The bump stops are definitely needed to be fairly firm up front (especially when using soft primary springs) in order to add enough support for the load transfer and to protect the suspension under large bottoming events. My preference (on the cars where enthusiasts want to enjoy better handling, like a VW GTi, Civic Si, Miata, etc.) would be to offer an 'sport' option that actually had firmer main springs, less-stiff front bump stops, and actually allowed the car to 'dance' and be more playful. The ride quality would be firmer on smaller oscillations BUT the handling would be more consistent and the car more capable. In most of the strut-based applications I've looked at, it is fairly safe to trim up to 1 inch off the front bump stop (again, this is NOT advice, just sharing my own experience, every vehicle damper and travel is unique). I typically trim the upper section of the bump stop to keep the progressive 'nose' on the lower end of the stop. I think it would be possible to design a MacPherson strut suspension that has more travel by using a shorter strut body and a longer, softer bump stop, along with a bit firmer primary springs. If you stayed in the 1.5-1.7 Hz range in the front and about 1.7-1.9 Hz rear, you would have a true 'Dual-Purpose', or GT setup. It seem largely an 'all-or-nothing' approach by the manufacturers. Either very soft 1.3 / 1.5 Hz front/rear rates with STIFF front stops and terminal understeer, or > 2.0 Hz (like Porsche GT3). Subaru seemed to have gotten this quite close with the STi around 1.7 / 1.9 Hz if memory serves although the front rebound damping was very firm. I prefer the WRX damping scheme which is actually more 'rally-like' than the STi. I think GTWorx does a very nice job with their tuning from what I've seen and tested. I appreciate the constraints that I'm aware of on the factory side of suspension tuning. What they do will give a softer overall ride on most decent roads, especially the non-sport models. What I object to is the terrible pitching that results from the DOMINANCE of the front bump stop + front rebound damping that causes terminal pitch when in cornering or on a bump road. I think they are so concerned with providing a neutral-handling setup (probably because honestly most people are at best average intelligence and half the people are dumber than that) so a car that required a countersteer correction would freak most drivers out. If as an enthusiast you're willing to have a bit firmer ride with more consistent suspension response over ALL types of roads, then you'll find your car more fun with the Ride Harmony approach. I'm very happy you're able to successfully apply these ideas and methods! I didn't invent Flat Ride (in case you didn't know! ;) ) but I love how useful and foundationally beneficial it is. Andrew goes into great detail and is really tapped into the BMW market for modifications that yield benefits not just marketing hype.
@@SuspensionTruth Thanks a lot again for the super deep reply. I can see why BMW/Porsche have taken that approach and frankly it makes sense if you are appealing to a broad audience to sell cars :) Maybe their shorter suspension travel approach is due in some part to aerodynamics and lowering the CG (BMW) compared to a car that has a relatively lower CG for what it is due to the engine (WRX/STI). WRX is already a brick as far as aerodynamics and more of a rally oriented purpose from the start. Again, speculation from my part. One car that I owned and loved it's handling was a Jaguar XJ SuperV8 (short wheel base 2004MY). Drove a 2009 from a friend and found it a very good compromise between ride and handling. Do you have any take on those cars setups? Very interested on your opinion. In a way, the manufacturer's compromises to have a broader appeal for their car makes place for great companies like yours who are able to refine a cars handling for enthusiasts like us that would like to enjoy the full potential of their platform. I don't know if you are familiar with the Alpine A110, I own one (replaced the E92 M3). I love the handling but found the car strangely damped, it has a relatively stiff ride at slow speeds but lots of pitch and roll at quite a faster pace on fast roads. So naturally, I find myself looking at suspension options but I want to make an educated choice.
Not familiar with the Jag but I think over the years the tuning on those British-origin cars has gotten more sophisticated. The Lotus Elise (early 2000s) I characterized and drove / autocrossed had pitch and was a miserable street ride. Lots of rebound-bias as well, soft compression. Your Alpine sounds fun. I think the gas force could be a factor in why the slow speed is stiff (also firm low speed damping can contribute) and then the soft springs and almost-certainly soft overall compression damping with more rebound will give poor body control. Whenever possible, I like to test a factory front and rear damper and spring (sometimes bump stops as well) to see what they had in mind as a basis to make improvements upon toward a client's goals. I always want to understand and respect the factory's approach and then see how can we tailor your FCM Elite suspension to your needs. I'm grateful for the opportunity to take a vehicle that's already gone through the incredibly challenging process of being made road worthy to then debate finer points of handling and grip. First world problems, to be sure! I feel the most pain for people in countries that may not have the ability or understanding to choose 'rally-style' tuning or Flat Ride on vehicles that deal with very poor roads. Riding in an Audi TT on bumpy Polish streets, plus taxis through Bucharest, were both eye-opening...
fantastic video - as always! i have been wanting to become an FCM Elite client for a while now, i am hoping 2025 is the year. what company changes are coming up?
Thanks, Peter. I've got another several in this series, plus a shorter one called 'Qualify Your Vendor' so you'll have clear questions to ask and expect answers from any suspension vendor (or even an OEM / off the showroom!). The other videos in this series will build upon each other so you or anyone will have a clearer understanding of what my approach is, why I find it superior, and how to ask good questions and make smarter buying decisions. Changes include a relocation in the near future. Been wanting to for years but it's finally in process. Further details will be provided on a need-to-know basis!
Check the description for Time Stamps and additional video links! AI-generated transcript also available.
Nice to See you making videos again. 🙂 As always very good infos and easy to understand.
Regards from Germany
✌️
Thanks my friend, I took a long break indeed. Gathering steam to put some thoughts together in a more coherent way. I intend for this series to be a one-stop reference and guide. I hope all is well with you and your passions!
Very educational 👍
Great video. Does the short suspension travel at the front on the models you mention have something to do with the fact they are McPherson front suspension types? They typically gain camber over a short suspension travel so I would think they would like to limit the travel in order to remain in that camber gain range? Does the choice of the front suspension setup also affect the way the dampers are setup from the factory?
And finally, what differences can you see on a factory damper/spring/bump stop setup with a front double wishbone suspension?
Sorry if these questions are dumb, I'm just someone interested in suspension setup but I have no formal engineering education. Just a car enthusiast.
Thanks!
Yes, a MacPherson strut with high motion ratio (nearly 1:1) will have less travel at the damper than an inboard-mounted double-wishbone (often 0.8:1 or lower). However, the relative wheel travel is still comparable. In the M2C video I mentioned on Farkle's channel, there was 18mm of strut travel before the bump stop starts to engage compared to 33mm at the rear. Taking into account the motion ratio, that means the front gets into the bump stops after 3/4 inch of wheel travel. That's not a lot and it's very common on most cars, especially 'sport' models. On an earlier Miata (the infamous 'R package') with double-wishbone geometry, the front bump stops were actually engaging at static ride height! The non-R models had longer springs and more clearance, but the bump stop engagement was still occurring frequently in straight-line driving and especially as soon as you begin cornering.
Video here (Deep Dive on M2 suspension, part 2):
ruclips.net/video/eUhJzOu3E2Q/видео.html
Actually, the MacPherson geometry LOSES camber faster than it gains - you might be thinking of the double-wishbone or SLA (Short-Long Arm) which actually does gain significant camber as the suspension goes into compression. The type of suspension would affect the relative forces used since you need less overall damping on a strut vs. an inboard-mounted shock. Otherwise, the consideration is really how much weight is there and what ride frequency are you targeting.
I see more force being used on a double wishbone (again, due to lower motion ratio) vs. a strut. The springs are stiffer as well. The bump stops are often similar stiffness with a similar ratio of front bump stop stiffer than rear. There are more commonalities between geometries than differences, but the differences scales with motion ratio and vehicle application. A sport coupe or sport sedan suspension will be tuned stiffer than a comfort or pure passenger application.
There are videos you can watch on my channel and elsewhere to gather more information. I have another several videos coming out in this series plus the 'Qualify your Vendor' (set of 2 videos) as a way to summarize these Crucial Ride Harmony concepts into actionable questions to ask a potential suspension supplier. If you have more questions, I encourage you to save your septims and purchase a consultation session.
I appreciate your interest and hope you continue to get value from this information!
@@SuspensionTruth Thank you for getting back on those questions. For the camber gain over a short amount of suspension travel, I was referring in my head to a camber change graph that I saw of a VW Golf GTI (If i remember correctly), it has a plain McPherson setup not the type used on Porsches and BMW's. I would have thought that was the reason to limit the suspension travel on a sports car application on a McPherson strut and thus using a higher spring rate via the bump stop (sorry this is speculation of course, again, no formal training) when driving hard and a softer spring rate on the spring in order to preserve some sort of comfort at normal speeds and driving.
My question really is that if the reason manufacturer had to compromise on how they handle the spring rates (spring + bump stop) was in order to compensate for the front suspension design limitations for the desired application (turning a sedan into a sports car). I had an E92 M3 and I was very surprised on how little suspension travel it had.
I've watched all your videos (we race an NA Miata with some friends and followed a lot of your guidelines which are great advice!) and also watched Farkle''s video which is very interesting.
Thanks again!
@@fedezyl My pleasure, thanks for engaging. This is an interesting article talking about the use of bump stops, especially modern 'micro-cellular polyurethane' (MCU) which are a superior design vs. older rubber style stops (pre-2000s). www.vehicledynamicsinternational.com/features/insights-into-bump-stop-tuning.html
The bump stops are definitely needed to be fairly firm up front (especially when using soft primary springs) in order to add enough support for the load transfer and to protect the suspension under large bottoming events. My preference (on the cars where enthusiasts want to enjoy better handling, like a VW GTi, Civic Si, Miata, etc.) would be to offer an 'sport' option that actually had firmer main springs, less-stiff front bump stops, and actually allowed the car to 'dance' and be more playful. The ride quality would be firmer on smaller oscillations BUT the handling would be more consistent and the car more capable.
In most of the strut-based applications I've looked at, it is fairly safe to trim up to 1 inch off the front bump stop (again, this is NOT advice, just sharing my own experience, every vehicle damper and travel is unique). I typically trim the upper section of the bump stop to keep the progressive 'nose' on the lower end of the stop.
I think it would be possible to design a MacPherson strut suspension that has more travel by using a shorter strut body and a longer, softer bump stop, along with a bit firmer primary springs. If you stayed in the 1.5-1.7 Hz range in the front and about 1.7-1.9 Hz rear, you would have a true 'Dual-Purpose', or GT setup. It seem largely an 'all-or-nothing' approach by the manufacturers. Either very soft 1.3 / 1.5 Hz front/rear rates with STIFF front stops and terminal understeer, or > 2.0 Hz (like Porsche GT3). Subaru seemed to have gotten this quite close with the STi around 1.7 / 1.9 Hz if memory serves although the front rebound damping was very firm. I prefer the WRX damping scheme which is actually more 'rally-like' than the STi. I think GTWorx does a very nice job with their tuning from what I've seen and tested.
I appreciate the constraints that I'm aware of on the factory side of suspension tuning. What they do will give a softer overall ride on most decent roads, especially the non-sport models. What I object to is the terrible pitching that results from the DOMINANCE of the front bump stop + front rebound damping that causes terminal pitch when in cornering or on a bump road. I think they are so concerned with providing a neutral-handling setup (probably because honestly most people are at best average intelligence and half the people are dumber than that) so a car that required a countersteer correction would freak most drivers out.
If as an enthusiast you're willing to have a bit firmer ride with more consistent suspension response over ALL types of roads, then you'll find your car more fun with the Ride Harmony approach. I'm very happy you're able to successfully apply these ideas and methods! I didn't invent Flat Ride (in case you didn't know! ;) ) but I love how useful and foundationally beneficial it is. Andrew goes into great detail and is really tapped into the BMW market for modifications that yield benefits not just marketing hype.
@@SuspensionTruth Thanks a lot again for the super deep reply. I can see why BMW/Porsche have taken that approach and frankly it makes sense if you are appealing to a broad audience to sell cars :)
Maybe their shorter suspension travel approach is due in some part to aerodynamics and lowering the CG (BMW) compared to a car that has a relatively lower CG for what it is due to the engine (WRX/STI). WRX is already a brick as far as aerodynamics and more of a rally oriented purpose from the start. Again, speculation from my part.
One car that I owned and loved it's handling was a Jaguar XJ SuperV8 (short wheel base 2004MY). Drove a 2009 from a friend and found it a very good compromise between ride and handling. Do you have any take on those cars setups? Very interested on your opinion.
In a way, the manufacturer's compromises to have a broader appeal for their car makes place for great companies like yours who are able to refine a cars handling for enthusiasts like us that would like to enjoy the full potential of their platform.
I don't know if you are familiar with the Alpine A110, I own one (replaced the E92 M3). I love the handling but found the car strangely damped, it has a relatively stiff ride at slow speeds but lots of pitch and roll at quite a faster pace on fast roads. So naturally, I find myself looking at suspension options but I want to make an educated choice.
Not familiar with the Jag but I think over the years the tuning on those British-origin cars has gotten more sophisticated. The Lotus Elise (early 2000s) I characterized and drove / autocrossed had pitch and was a miserable street ride. Lots of rebound-bias as well, soft compression.
Your Alpine sounds fun. I think the gas force could be a factor in why the slow speed is stiff (also firm low speed damping can contribute) and then the soft springs and almost-certainly soft overall compression damping with more rebound will give poor body control. Whenever possible, I like to test a factory front and rear damper and spring (sometimes bump stops as well) to see what they had in mind as a basis to make improvements upon toward a client's goals. I always want to understand and respect the factory's approach and then see how can we tailor your FCM Elite suspension to your needs.
I'm grateful for the opportunity to take a vehicle that's already gone through the incredibly challenging process of being made road worthy to then debate finer points of handling and grip. First world problems, to be sure!
I feel the most pain for people in countries that may not have the ability or understanding to choose 'rally-style' tuning or Flat Ride on vehicles that deal with very poor roads. Riding in an Audi TT on bumpy Polish streets, plus taxis through Bucharest, were both eye-opening...
fantastic video - as always! i have been wanting to become an FCM Elite client for a while now, i am hoping 2025 is the year. what company changes are coming up?
Thanks, Peter. I've got another several in this series, plus a shorter one called 'Qualify Your Vendor' so you'll have clear questions to ask and expect answers from any suspension vendor (or even an OEM / off the showroom!). The other videos in this series will build upon each other so you or anyone will have a clearer understanding of what my approach is, why I find it superior, and how to ask good questions and make smarter buying decisions.
Changes include a relocation in the near future. Been wanting to for years but it's finally in process. Further details will be provided on a need-to-know basis!
Keep us posted please.