Hey Drivers! Thanks for supporting Haptic Garage with your viewership and good vibes. That is plenty to earn my gratitude but for those interested, there is a new "Thanks" button above that serves as a tip jar for sustaining the channel- never expected but always appreciated. Thanks for watching!
This is the most understandable and the best explanation of how a Beetle standard exhaust and heat riser work together I have yet to come across on the tube. Thank You! So glad I am a subscriber. I am a recent new parent ( Feb 22) of a fully restored 1971 Super and enjoy these types of "I get it" moments. Unfortunately my Super Beetle , named Ringo , suffers from a broken clutch cable guide in the tunnel (the one near the hand brake) and have not got the courage yet to open up the interior and the tunnel to weld the darn thing back up. Thank you for your efforts in posting this Beetle material!
Congrats campion05, I'm sure you have many good miles ahead in your '71 Super. I haven't had to make that repair yet, but a perfectly placed plug weld would be a super slick way to get it done. Then buy a lottery ticket. Thanks for the awesome comment and being a part of the fun!
I never understood the need for the heat risers until Chris called me one morning on his way to school. He said "Abbey stalled on me and the carb is covered in ice". Had no idea that was a thing. Abbey has an aftermarket exhaust and neither side had the whole drilled out. Once we did that she never iced up again. Thanks for sharing this, always a pleasure watching.
Isn't that crazy?!? I'm guessing it was a cool, high humidity morning. I'm glad you were able to resolve the problem. Do you recall what size hole you drilled? Maybe 1/4" so it could be done without drilling the side of that angled passage? I'm glad you enjoyed it, and look forward to seeing you both at the next show!
Thanks Adam, I saw (what I believe to be) Brazilian busses the other day- they were Bay Window busses with corner windows. Super cool. Anyway, thanks for watching and good luck with the heat riser!
Great video as always. So many people don’t understand how the heat riser works and how the aftermarket exhausts aren’t maximizing the efforts. With the fuel not puddling the intake, your spark plugs and pistons will thank you… also your mpg will increase some. Great job and explanation!
Thanks Gary! Agreed, the VW engineers are held in high regard in other areas but deserve a little more credit on this one. Thanks for always being so supportive!
You show things that are very helpful and not many people talk about. You also make it understandable for people with limited knowledge like myself. Keep making these great videos. They are very valuable for the VW community.
Not sure if you remember me but was a podcast guest on Mike's a couple years ago. I watched your's but just now subbed to your channel because I'm working on a 65 40h. Love your save a buck or two on these motors and great machine work. I worked with the machine shop guys at Boeing for 35 years and if I had the tools could do it in my shop. So seeing you do this is inspirimg.
Thanks Tim, great to have you with us and from one @GoodOldMike alum to another, it was a lot of fun hanging out with Mike and his son while the podcast was a thing.
Awesome test and results, Brent! I'd like to comment that the pipe on the right side going for the HR to the tailpipe was kind of anti-aesthetic in my opinion haha but hey, probably you were going for something easy, practical and besides, you were experimenting. I think that a more aesthetic one would bend following the exhaust pipe's path and connect at an angle so there's no exhaust flow issues. These are just my 2 cents, your build is excellent. This kind of encouraged me to get this done for the engine on my baywindow
Thanks VochoTalacha! Yeah, it's an ugly mod but as you alluded to we can improve the cosmetics on the next one. I had another idea that I may try although it's a little silly. All in fun of course! Good luck with the Bay bus, you'll have more space constraints than I had to deal with but I know you'll do something great.
Brent, my brother, this is NOT another great video. it is an exceptional video! Great information as well as a great "fix" that anyone could do! I cannot count the number of times i have messed around with the exhaust on these things. I had no idea at all (because I never even thought about checking the parts) that some or maybe even most or all aftermarket exhaust parts did not come properly engineered for the heat risers. actual holes missing, hard to believe! thanks for making this exceptional video brother!
Thanks Michael, I'm happy to share this with you! And thanks for popping into the Bug Fest '23 livestream yesterday; we finally found the illusive nocthback!
great test. that pipe on the right must have a sort off vacuum from that exhaust pipe. but when that temp drops to much, the intake will cool down to much at one side. the intake bellow the carb will freeze in the winter. these variables are interesting to see how everything react. well done sir, learned something new.
Thanks VW Beetle Oval 1955. It may not be an actual vacuum but relatively lower pressure would have a similar effect. I should have mentioned icing more directly in the video- I'm in a climate where it's rarely an issue but for many people it's the main reason they need a heat riser. Cooler days with high humidity are the most likely to cause that issue, which sounds like the kind of day a person really does not want to break down! Thanks for watching and keep up the good work!
Thanks Scott! It's easier to delete some of these less understood parts but I agree with your sentiment- the car is more fun when it is running great vs. running OK. Now if I could just get to the running great part...
Great video on a very misunderstood subject. i see so many cars with the heat risers completely cut off ! If the factory felt it didn't need those parts they would have left them off . Well done on rectifying the situation.
Thanks Van Zelst! I agree; they could have saved some manufacturing costs by leaving this off. To each their own but the results are convincing. Thanks for watching!
Also have to think of temperatures of the location where the beetle was made and used .. like here in TX to is to damn hot.. those aren't necessary. My 2 cents
Thanks so much for this, I am sure you have answered the question of what a guy needs to do if you want to say run a single 44 IDF to a after market exhaust. I see video after video of people running those combinations without any heat risers at all? and you just explained exactly what needs to be done. Thanks again!
Saw your video and decided to check my headers as I was having alot of throttle hesitation....Fake heat ports! No out let or inlet. I drilled out and bug is really taking off good now, thanks so much for the info!
this was a fantastic video. simple and clear explanation with a simple and straightforward solution. i like it. i feel like i've learned some new stuff today!
Woohoo! Thanks Annie, and keep the engine project updates coming. I've seen your posts on IG and will be catching up on the latest RUclips video. Great work as always!
Well finally a straight forward explanation of How the heat riser piping works. Great creativity on getting hooked into the exhaust you have. Now I have to go fix the blocked risers on my bus. Thank you.
Fantastic experiment! I am messing around with my bus' intake and 4-into-1 exhaust header right now and am almost certain I should switch to a stock muffler to get my heat risers operating like they are supposed to. Thank you, man!
Thanks Christian! I run a stock muffler on my split bus and have no issues with the heat riser. However, a 4 into 1 is generally regarded as a worthwhile upgrade; you may consider routing the low pressure end of the heat riser to the collector. Good luck with your project!
@@HapticGarage i just checked my 4-into-1...it has been drilled through to receive the exhaust gasses but, like all the rest, the right side looks just like the left side in terms of pipe length. Keep up the fantastic work, man.
Dude this is insane. First I had no idea the physics behind the heat riser and that they even made fake heat risers. I’m gonna go check mine today. I actually hope they are fake so I can cut them off since I’m running dual carbs. But I’m also excited cuz I can help my friend who has a stock still has a single carb. You rock haptic!!!
Educational! That might have been one of the best explanations of the heat risers function and purpose I have ever heard. Hard to believe exhaust systems are not only made but mass produced and accepted by the consumers that fall short of the needs of the motor. I know it's off road/baja exhaust but still. I've actually had a mechanic tell me the heat riser doesn't matter. Destroying those myths from the wild and woolly VW days of the past one at a time!
Thanks Adam! I agree some of the parts for sale are less than ideal. As we know more, we'll make better choices and the suppliers will follow! Thanks for your insightful thoughts.
Really great video ( nice edit). A well thought out and well executed repair/upgrade. It would be interesting to see what temperatures would be on a riser with a stock exhaust. No matter, a 100 degree increase is a great improvement. Well done.
Thanks Aussie Beatle, this was a fun project. Next time I drive the bus I'll take a quick reading. Whether it is higher or lower, I'm guessing it would be more correct for the design. I think I'll raise the RPMs a little too because it seemed like the temps settled down as the engine idled. This will be fun! Thanks as always for being a part of the channel, great to have you here.
Great minds think alike Donald. I'm still pondering that one- seems it would be good for a full bodied car. That would keep the heat inside the pipe and out of the cooling air intake. And to your point, it would result in more manifold heat. Just not sure what the "right" amount of heat is; seems probable that there is a sweet spot. Not sure if the principles of a cold air intake apply here; the two are on opposite sides of the carb. May take a lot of testing/data to answer that one but I agree it would be interesting!
For the original exhaust, the standard exhaust pipes even need a certain depth to create the right vacuum! Very important to prevent freezing. So don't buy false unless you are with dual carbs but then you don't need that attachment either.🤷🏼♂️😜
You are absolutely right with your last words.... Raw fuel in the cylinders will shorten the life! That's why it's also still important to check your spark plugs now and then!
Thanks Davy, yes- exhaust systems done well are a complex bit of engineering. I've scratched the surface learning about the "scavenging effect" and similar- I can't pretend to understand it all but it's fascinating. Thanks for watching!
Really appreciate you making this video. I just ordered a 4 into 1 tri-mill that has the risers but believe I will run into the same issue in that they probably aren't drilled through. The whole concept makes sense and I wonder why the aftermarket companies didn't take this into consideration. I might have to find someone to do this to my new headers once they come in. Not really a fabricator or welder myself. Would have liked to see what the temps were if the holes had been opened to start with. Great video!
You're most welcome Mitch, thanks for watching! FI think they leave them closed for people not using a center mounted carb (no need for a heat riser). The idea may be to drill what ever size hole you can without drilling out the side. I'd prefer they drill them and provide block-off plates but that's just me. When I do a 4 into 1 in the future, I'll probably route the riser's output to the collector. It would definitely be a conversation starter to the sharp eyed observer... Thanks again!
In case it hasn't already been mentioned, and to hopefully help avoid confusion, rear cylinder on the left is #4, not #3. Other than that, I think this was probably very informative for a lot of people.
Thanks for catching that @408 SIXBBL, I know better but messed it up and missed it in editing. Sheesh. I've added a correction in the description, hopefully that minimizes any confusion. Thanks for watching!
Hi, Brent, As usual, a great instructional and well-Explained experiment that surely did a great difference to the Dweezil`s engine. I´m happy I have not to do some likely to my VW T3 I did convert after I bought a new Factory rebuild JX Diesel engine that I made of a Turbo Diesel. with great driving differences for the better at the same time I installed a 5-speed Transmission who made the driving more pleasant and less use of fuel. as always great to follow you with your escapades in the Haptic Garage🇺🇸⭐️❤️🇳🇴🇳🇱☮️💥.Greetings.Hubertus.
Thanks Hubertus! Wow, a turbo diesel- I'm sure that is a great driving T3. Also wish my bus had a 5th gear; I've tried to shift into 5th more than once but it's only a 4 speed! Great to hear from you and keep up the good work!
I've drilled them out before, had to drill out under the intake, but never had a stock muffler or known the reason why... I'm going to make my own exhaust one that does not run underneath the valve covers! And I will take your bit of knowledge and use it Thank you
Great video, did you check the heat riser tube to see if it was clogged? It should not be clogged since you had no hole drilled. Some new exhausts will not have the holes drilled. You can use a gasket with a 1/4inch hole and the other side a 1/2 inch hole. That's if you don't have the tube going down to a low pressure. Nice work .
Hey David, I meant to check but I expect it's clear- I cleaned it out during the build a few years ago and, as you said, the passages were not drilled. Thanks for the info!
Great video! Our bug is currently in the same configuration, same exhaust setup with opposing exhaust pulses 🤦🏻♂️. I think the only thing I'll do differently is just move the flange on the exit side up to the straight section of the heat risers... And just run it straight to the end of that muffler without the bends. 🤷🏻♂️
Thanks John! Not a bad option with an open engine compartment like on a baja. Not so easy on a full bodied car because the bend gets you down through the cooling tin. Would have been fine on Dweezil with this buggy exhaust that would never fit a full sedan. Thanks for watching!
@@HapticGarage previous owner actually cut holes in the rear fenders for the chrome tips and left the rear engine plate you mentioned off... It's a real hack job. All projects for another day 🤦.
👍 When aftermarket companies started selling the 4 into 1 headers back in the 70's. They had headers with the tubing to work right with the stock solex. But only a few folks bought them. Check out the catalogs from that time period.
Just subbed to your channel - its great! :-) I just spent many hours unblocking a heat riser pipe (caustic soda, heat, cable on a drill etc) ....... always check its clear and clear it out :-)
Hello A Gee, absolutely. This one was cleared when the engine was assembled and, due to the aftermarket exhaust, had no opportunity to clog. But always worth checking. Thanks for watching!
I think as long as that tube gets warm enough to keep the fuel vapor it really does not matter. I have been running single carbs for 40 years. and the only thing I can see that would make a difference is warm up time. When say number 2 fires. there is a vacuum at 4.....right behind the pop there is a vacuum on each fire. as the fire.....For instance there is a fire in front of that fire there is a pressure behind it there is a vacuum in the middle the pulse.....Yes that heat riser will have flow going through it back and forth but it is just heats the manifold enough to not frost I should be fine. I get 22 mpg in my bus with a 1904 with that heat style heat riser. It is cold blooded because of the heat coming on slow but after that is is just fine. I dont run dual carbs because you loose torque. This is all from the engineering books. shorter intake more HP less torque longer intake more torque.
Hey Mike! I believe you are describing the "scavenging" effect. I'm happy with the results I'm getting but agree that single carbs have some great advantages. Simplicity is high on the list. Have a great weekend!
I thought you would have cleaned the entire tubing with a old braided wire....maybe it's full of carbon. ;) Great job though....I always enjoy watching your content. Thanks !!! ~Bryan-Homer Alaska
Thanks Bryan! The riser was cleaned out when the engine was assembled and saw very few miles before this modification so it was clear. But you're right- it would especially be important to check that if the holes were present on an aftermarket exhaust. Thanks for watching!
Thanks Jeff! I have a couple 4 into 1 exhausts laying around. I may try out the one that fits low under the decklid (I kinda like the chopped rear/full decklid thing on Dweezil- it keeps the rain off but the engine access is great!)
Good question BigE- I meant to double check but missed the opportunity. However, I cleaned this heat riser out during the build and it has not had any exposure to exhaust since so I'm guessing it's still clear. I expect a perfectly functioning riser tube would drop in temperature as the heat energy is transferred into the intake tube. It would be interesting to measure the temp on others to make comparisons. Thanks for the question!
Thanks James, a weldable/maleable fitting of that type would have made this easier. This project was another example of just using what we have. Thanks for the suggestion!
Thanks Kombi Garage. Yes- the riser was cleared when the engine was assembled a few years ago and had no opportunity to become clogged with the aftermarket exhaust. But that is correct- they do become clogged with soot over time and even worse with an improperly designed exhaust. Thanks for watching!
A 10 degree reduction in cylinder head temp???? Were you able to confirm that? If so, that’s huge!!! Also, can you do a short on your cylinder head temp sensor/gauge? Make/model, sensor location, etc? Not really a fan of the CHT senders that sit under the spark plug…hoping you found something that maybe mounts directly to the head or fins in some way.
Yeah, that was a big dip in temps on a similar run. I'd count that as a casual observation; anything definitive would need a lot more data before/after. Either way, a better running engine is going to live a happier life! I have a Dakota Digital CHT gauge purchased a decade ago. So far it's been great (albeit a little ugly). Unfortunately the thermocouple fits under the plug. There is a sensor boss on some of the later heads (for fuel injection?) but seems the plug area gets a more direct read. Just a hassle when dealing with plugs. Thanks for watching!
Seems that way GT, but I'm guessing they leave it undrilled for people running dual carbs. I'd prefer they drill the holes and provide block offs, but I guess that would raise the price a little. The good news is, we can fix it!
@@GT.Bugger Correct- duals don't need it because they sit right on top of the heads. No chance for icing or de-atomization. I've never used duals but that's what people say and it makes sense to me. And yes, there's always a way!
That would be a fun project Robert. A smaller drill bit (maybe 1/4") would be needed to squeeze around the bend but could be done. Thanks for watching!
Hello Joe, the manifold tube was cleaned out when the engine was assembled a few years ago but you're right, they do become clogged. Thanks for watching!
Hi Everton, thanks for watching. I'm not sure I understand the question but if you are asking about a heat riser block off plate, it's there to prevent an exhaust leak when the header has been drilled through. The block off plate wouldn't be necessary on an exhaust like mine where there was no hole until I drilled it myself. I'm guessing a possible reason for manufacturing them this way is so a person running dual carbs (who would not be using a heat riser) doesn't have to use block off plates. Sounds like a good excuse anyway! Good luck with your project!
I expect so- a smooth running engine is more efficient and that means better mileage. This particular engine needs other improvements too but this is a good start.
Aftermarket headers come with un-drilled risers on purpose. It's easier to take metal away than put it back. People running dual carbs can leave the pipes closed up. Everyone else can drill holes. Odds are, more people own drills than welding kit. Another thing I've heard of was to drill different sized holes on each side. With the way VW engines fire (left-left-right-right) the tiny difference in flow is enough to keep hot gasses flowing one-way. It doesn't need much to get the job done. A 3/16 on one side and 5/16 on the other fit the bill. While what you did was far more correct, it's more work than the exhaust's designers intended. Edit: And block-off plates leak more than un-drilled holes.
Hi Imnotgoing Sideways, thanks for the input. I agree the aftermarket manufacturers are doing it this way intentionally, and hope they would at least advise holes be drilled when a heat riser is being used with a single carb. In support of the different sized holes concept, I've seen optional restrictors used in other applications involving exhaust waste heat for whatever circumstances required them. Additionally, there are ways to improve on the original VW design but I don't feel this is one of them. I prefer this approximation of the original plumbing for its approach to high and low pressure areas that support the flow of heat through the system. And I kinda like working on my car. Thanks again for the contrast, it's a healthy thing to hear different perspectives.
Hey Drivers! Thanks for supporting Haptic Garage with your viewership and good vibes. That is plenty to earn my gratitude but for those interested, there is a new "Thanks" button above that serves as a tip jar for sustaining the channel- never expected but always appreciated. Thanks for watching!
This is the most understandable and the best explanation of how a Beetle standard exhaust and heat riser work together I have yet to come across on the tube. Thank You! So glad I am a subscriber. I am a recent new parent ( Feb 22) of a fully restored 1971 Super and enjoy these types of "I get it" moments. Unfortunately my Super Beetle , named Ringo , suffers from a broken clutch cable guide in the tunnel (the one near the hand brake) and have not got the courage yet to open up the interior and the tunnel to weld the darn thing back up. Thank you for your efforts in posting this Beetle material!
Congrats campion05, I'm sure you have many good miles ahead in your '71 Super. I haven't had to make that repair yet, but a perfectly placed plug weld would be a super slick way to get it done. Then buy a lottery ticket. Thanks for the awesome comment and being a part of the fun!
Nice fix man! Great video!
Thanks CT! I hope the move is going well!
I never understood the need for the heat risers until Chris called me one morning on his way to school. He said "Abbey stalled on me and the carb is covered in ice". Had no idea that was a thing. Abbey has an aftermarket exhaust and neither side had the whole drilled out. Once we did that she never iced up again. Thanks for sharing this, always a pleasure watching.
Isn't that crazy?!? I'm guessing it was a cool, high humidity morning. I'm glad you were able to resolve the problem. Do you recall what size hole you drilled? Maybe 1/4" so it could be done without drilling the side of that angled passage? I'm glad you enjoyed it, and look forward to seeing you both at the next show!
my Brazilian bus has nothing connected to the heat risers I always suspected something was missing 😂 always a pleasure to watch
Thanks Adam, I saw (what I believe to be) Brazilian busses the other day- they were Bay Window busses with corner windows. Super cool. Anyway, thanks for watching and good luck with the heat riser!
Classic Haptic Garage. Experimentally fabricating something from nothing along with cool edits and groovy tunes.
Thanks Greg, this was a fun project and I had some fun with the video too. Thanks for always being so supportive!
Great video as always. So many people don’t understand how the heat riser works and how the aftermarket exhausts aren’t maximizing the efforts. With the fuel not puddling the intake, your spark plugs and pistons will thank you… also your mpg will increase some.
Great job and explanation!
Thanks Gary! Agreed, the VW engineers are held in high regard in other areas but deserve a little more credit on this one. Thanks for always being so supportive!
You show things that are very helpful and not many people talk about. You also make it understandable for people with limited knowledge like myself. Keep making these great videos. They are very valuable for the VW community.
Thanks Zimm, I'm happy to have such awesome people with whom to share and learn from!
Not sure if you remember me but was a podcast guest on Mike's a couple years ago. I watched your's but just now subbed to your channel because I'm working on a 65 40h. Love your save a buck or two on these motors and great machine work. I worked with the machine shop guys at Boeing for 35 years and if I had the tools could do it in my shop. So seeing you do this is inspirimg.
Thanks Tim, great to have you with us and from one @GoodOldMike alum to another, it was a lot of fun hanging out with Mike and his son while the podcast was a thing.
Awesome test and results, Brent!
I'd like to comment that the pipe on the right side going for the HR to the tailpipe was kind of anti-aesthetic in my opinion haha but hey, probably you were going for something easy, practical and besides, you were experimenting. I think that a more aesthetic one would bend following the exhaust pipe's path and connect at an angle so there's no exhaust flow issues. These are just my 2 cents, your build is excellent.
This kind of encouraged me to get this done for the engine on my baywindow
Thanks VochoTalacha! Yeah, it's an ugly mod but as you alluded to we can improve the cosmetics on the next one. I had another idea that I may try although it's a little silly. All in fun of course! Good luck with the Bay bus, you'll have more space constraints than I had to deal with but I know you'll do something great.
Brent, my brother, this is NOT another great video. it is an exceptional video! Great information as well as a great "fix" that anyone could do! I cannot count the number of times i have messed around with the exhaust on these things. I had no idea at all (because I never even thought about checking the parts) that some or maybe even most or all aftermarket exhaust parts did not come properly engineered for the heat risers. actual holes missing, hard to believe! thanks for making this exceptional video brother!
Thanks Michael, I'm happy to share this with you! And thanks for popping into the Bug Fest '23 livestream yesterday; we finally found the illusive nocthback!
great test. that pipe on the right must have a sort off vacuum from that exhaust pipe. but when that temp drops to much, the intake will cool down to much at one side. the intake bellow the carb will freeze in the winter. these variables are interesting to see how everything react.
well done sir, learned something new.
Thanks VW Beetle Oval 1955. It may not be an actual vacuum but relatively lower pressure would have a similar effect. I should have mentioned icing more directly in the video- I'm in a climate where it's rarely an issue but for many people it's the main reason they need a heat riser. Cooler days with high humidity are the most likely to cause that issue, which sounds like the kind of day a person really does not want to break down! Thanks for watching and keep up the good work!
Great video, fun and educational. I'm always shocked how many people run a single carb but with the heat risers removed or blocked off.
Thanks Scott! It's easier to delete some of these less understood parts but I agree with your sentiment- the car is more fun when it is running great vs. running OK. Now if I could just get to the running great part...
It's so hot here in Texas those heat risers just don't need them
Great video on a very misunderstood subject. i see so many cars with the heat risers completely cut off ! If the factory felt it didn't need those parts they would have left them off . Well done on rectifying the situation.
Thanks Van Zelst! I agree; they could have saved some manufacturing costs by leaving this off. To each their own but the results are convincing. Thanks for watching!
Also have to think of temperatures of the location where the beetle was made and used .. like here in TX to is to damn hot.. those aren't necessary.
My 2 cents
Thanks so much for this, I am sure you have answered the question of what a guy needs to do if you want to say run a single 44 IDF to a after market exhaust. I see video after video of people running those combinations without any heat risers at all? and you just explained exactly what needs to be done. Thanks again!
Thanks Justwastingtime, I'm glad you found this useful and I appreciate your awesome comment!
Saw your video and decided to check my headers as I was having alot of throttle hesitation....Fake heat ports! No out let or inlet. I drilled out and bug is really taking off good now, thanks so much for the info!
Isn't that wild?!? Great work getting it fixed, I'm glad your Bug is happy with the changes. Thanks for the follow up!
this was a fantastic video. simple and clear explanation with a simple and straightforward solution. i like it. i feel like i've learned some new stuff today!
Woohoo! Thanks Annie, and keep the engine project updates coming. I've seen your posts on IG and will be catching up on the latest RUclips video. Great work as always!
Well finally a straight forward explanation of How the heat riser piping works. Great creativity on getting hooked into the exhaust you have. Now I have to go fix the blocked risers on my bus. Thank you.
Thanks Cathy and Greg, I'm glad this helped. Good luck on your version, let us know how it goes!
Fantastic experiment! I am messing around with my bus' intake and 4-into-1 exhaust header right now and am almost certain I should switch to a stock muffler to get my heat risers operating like they are supposed to. Thank you, man!
Thanks Christian! I run a stock muffler on my split bus and have no issues with the heat riser. However, a 4 into 1 is generally regarded as a worthwhile upgrade; you may consider routing the low pressure end of the heat riser to the collector. Good luck with your project!
@@HapticGarage i just checked my 4-into-1...it has been drilled through to receive the exhaust gasses but, like all the rest, the right side looks just like the left side in terms of pipe length. Keep up the fantastic work, man.
Dude this is insane. First I had no idea the physics behind the heat riser and that they even made fake heat risers. I’m gonna go check mine today. I actually hope they are fake so I can cut them off since I’m running dual carbs. But I’m also excited cuz I can help my friend who has a stock still has a single carb. You rock haptic!!!
That's great Creature Teacher, I'm glad you'll make this info useful by doing. Good luck and let us know how it goes!
8 minutes in and I've already learned so much from this video! Nice work!
Thanks Dream Wrench, happy to share and its always great to hear from you!
Educational! That might have been one of the best explanations of the heat risers function and purpose I have ever heard. Hard to believe exhaust systems are not only made but mass produced and accepted by the consumers that fall short of the needs of the motor. I know it's off road/baja exhaust but still. I've actually had a mechanic tell me the heat riser doesn't matter. Destroying those myths from the wild and woolly VW days of the past one at a time!
Thanks Adam! I agree some of the parts for sale are less than ideal. As we know more, we'll make better choices and the suppliers will follow! Thanks for your insightful thoughts.
Like always nothing but fun! Problem solution getting the best bang for efficiency ! Amazing video ! Thank you !
Thanks Neal, I'm happy to share!
Really great video ( nice edit). A well thought out and well executed repair/upgrade. It would be interesting to see what temperatures would be on a riser with a stock exhaust. No matter, a 100 degree increase is a great improvement. Well done.
Thanks Aussie Beatle, this was a fun project. Next time I drive the bus I'll take a quick reading. Whether it is higher or lower, I'm guessing it would be more correct for the design. I think I'll raise the RPMs a little too because it seemed like the temps settled down as the engine idled. This will be fun! Thanks as always for being a part of the channel, great to have you here.
Would be interesting to see what a hear wrap on the high pressure side riser would add.
Great minds think alike Donald. I'm still pondering that one- seems it would be good for a full bodied car. That would keep the heat inside the pipe and out of the cooling air intake. And to your point, it would result in more manifold heat. Just not sure what the "right" amount of heat is; seems probable that there is a sweet spot. Not sure if the principles of a cold air intake apply here; the two are on opposite sides of the carb. May take a lot of testing/data to answer that one but I agree it would be interesting!
For the original exhaust, the standard exhaust pipes even need a certain depth to create the right vacuum! Very important to prevent freezing. So don't buy false unless you are with dual carbs but then you don't need that attachment either.🤷🏼♂️😜
You are absolutely right with your last words.... Raw fuel in the cylinders will shorten the life! That's why it's also still important to check your spark plugs now and then!
Thanks Davy, yes- exhaust systems done well are a complex bit of engineering. I've scratched the surface learning about the "scavenging effect" and similar- I can't pretend to understand it all but it's fascinating. Thanks for watching!
Really appreciate you making this video. I just ordered a 4 into 1 tri-mill that has the risers but believe I will run into the same issue in that they probably aren't drilled through. The whole concept makes sense and I wonder why the aftermarket companies didn't take this into consideration. I might have to find someone to do this to my new headers once they come in. Not really a fabricator or welder myself. Would have liked to see what the temps were if the holes had been opened to start with. Great video!
You're most welcome Mitch, thanks for watching! FI think they leave them closed for people not using a center mounted carb (no need for a heat riser). The idea may be to drill what ever size hole you can without drilling out the side. I'd prefer they drill them and provide block-off plates but that's just me. When I do a 4 into 1 in the future, I'll probably route the riser's output to the collector. It would definitely be a conversation starter to the sharp eyed observer... Thanks again!
In case it hasn't already been mentioned, and to hopefully help avoid confusion, rear cylinder on the left is #4, not #3. Other than that, I think this was probably very informative for a lot of people.
Thanks for catching that @408 SIXBBL, I know better but messed it up and missed it in editing. Sheesh. I've added a correction in the description, hopefully that minimizes any confusion. Thanks for watching!
I would try running a rod through the heat riser, good chance it is stopped up with rust.
Great video.
Thanks @harleycruiser4331 this riser was cleaned during a preceding rebuild to resolve the problem you describe. Thanks for watching!
Hi, Brent, As usual, a great instructional and well-Explained experiment that surely did a great difference to the Dweezil`s engine. I´m happy I have not to do some likely to my VW T3 I did convert after I bought a new Factory rebuild JX Diesel engine that I made of a Turbo Diesel. with great driving differences for the better at the same time I installed a 5-speed Transmission who made the driving more pleasant and less use of fuel. as always great to follow you with your escapades in the Haptic Garage🇺🇸⭐️❤️🇳🇴🇳🇱☮️💥.Greetings.Hubertus.
Thanks Hubertus! Wow, a turbo diesel- I'm sure that is a great driving T3. Also wish my bus had a 5th gear; I've tried to shift into 5th more than once but it's only a 4 speed! Great to hear from you and keep up the good work!
@@HapticGarage Thank you Brent I surely do so, enjoy your weekend.greetings.hubertus
great work mate, I've got to repair the small pipe on the ute as its rusted again :(
Thanks Demop. Funny thing about exhaust parts, they always seem to rust. Good thing we know how to fix them!
Thanks for doing this. I enjoy all your work. This was not only interesting, but also very helpful! Cheers!!
Thanks Rich, glad to share and I appreciate your support. Thanks for watching!
Good vid and info! Glad to see you back at it after Nodough.
Thanks Robert! It was great chatting with you that day and I hope your travels went well. See you at the next one!
@@HapticGarage good talking to you also. Hope to see you again at an event. All good but a long ride!
I've drilled them out before, had to drill out under the intake, but never had a stock muffler or known the reason why... I'm going to make my own exhaust one that does not run underneath the valve covers! And I will take your bit of knowledge and use it
Thank you
Great video, did you check the heat riser tube to see if it was clogged? It should not be clogged since you had no hole drilled. Some new exhausts will not have the holes drilled. You can use a gasket with a 1/4inch hole and the other side a 1/2 inch hole. That's if you don't have the tube going down to a low pressure. Nice work .
Hey David, I meant to check but I expect it's clear- I cleaned it out during the build a few years ago and, as you said, the passages were not drilled. Thanks for the info!
Great video! Our bug is currently in the same configuration, same exhaust setup with opposing exhaust pulses 🤦🏻♂️. I think the only thing I'll do differently is just move the flange on the exit side up to the straight section of the heat risers... And just run it straight to the end of that muffler without the bends. 🤷🏻♂️
Thanks John! Not a bad option with an open engine compartment like on a baja. Not so easy on a full bodied car because the bend gets you down through the cooling tin. Would have been fine on Dweezil with this buggy exhaust that would never fit a full sedan. Thanks for watching!
@@HapticGarage previous owner actually cut holes in the rear fenders for the chrome tips and left the rear engine plate you mentioned off... It's a real hack job. All projects for another day 🤦.
Great video ! May have another project to do on the buggy I have the same set up 😁
Thanks Livin the life, these dual "canon" exhausts are fun aren't they?!?
👍 When aftermarket companies started selling the 4 into 1 headers back in the 70's. They had headers with the tubing to work right with the stock solex. But only a few folks bought them. Check out the catalogs from that time period.
That's pretty cool '76, thanks for the info. Did they connect the riser outlet to the collector?
@@HapticGarage
Yes.
@@vintage76vipergreenBeetle Makes sense. Thanks again for the info!
@@HapticGarage
Samba has photos of some in the gallery section.
Thanks '76, I just checked out a few. Love that site!
Just subbed to your channel - its great! :-)
I just spent many hours unblocking a heat riser pipe (caustic soda, heat, cable on a drill etc) ....... always check its clear and clear it out :-)
Hello A Gee, absolutely. This one was cleared when the engine was assembled and, due to the aftermarket exhaust, had no opportunity to clog. But always worth checking. Thanks for watching!
Good stuff!! The bug looks and sounds great.
Thanks John! I'm having a great time with this thing, and even better to share!
I think as long as that tube gets warm enough to keep the fuel vapor it really does not matter. I have been running single carbs for 40 years. and the only thing I can see that would make a difference is warm up time. When say number 2 fires. there is a vacuum at 4.....right behind the pop there is a vacuum on each fire. as the fire.....For instance there is a fire in front of that fire there is a pressure behind it there is a vacuum in the middle the pulse.....Yes that heat riser will have flow going through it back and forth but it is just heats the manifold enough to not frost I should be fine. I get 22 mpg in my bus with a 1904 with that heat style heat riser. It is cold blooded because of the heat coming on slow but after that is is just fine. I dont run dual carbs because you loose torque. This is all from the engineering books. shorter intake more HP less torque longer intake more torque.
Hey Mike! I believe you are describing the "scavenging" effect. I'm happy with the results I'm getting but agree that single carbs have some great advantages. Simplicity is high on the list. Have a great weekend!
I thought you would have cleaned the entire tubing with a old braided wire....maybe it's full of carbon. ;)
Great job though....I always enjoy watching your content. Thanks !!!
~Bryan-Homer Alaska
Thanks Bryan! The riser was cleaned out when the engine was assembled and saw very few miles before this modification so it was clear. But you're right- it would especially be important to check that if the holes were present on an aftermarket exhaust. Thanks for watching!
Brilliant and clever, thanks! Love your videos.
Thanks Mra Mra, I'm glad to have you with us!
Merged headers are king for engine life.......Now you have a 4 into one exhaust ...😁
Yup, 4 into 1 is the way to maximize. But I'm thinking this is more like 3 into 1.5. Or something. Thanks Jeff!
@@HapticGarage 4 into 1 Meyers Manx exhaust work work well on the bug
Thanks Jeff! I have a couple 4 into 1 exhausts laying around. I may try out the one that fits low under the decklid (I kinda like the chopped rear/full decklid thing on Dweezil- it keeps the rain off but the engine access is great!)
Did you check heat riser tubing on manifold for carbon build up? It can explain temperature drop along tubing.
Good question BigE- I meant to double check but missed the opportunity. However, I cleaned this heat riser out during the build and it has not had any exposure to exhaust since so I'm guessing it's still clear. I expect a perfectly functioning riser tube would drop in temperature as the heat energy is transferred into the intake tube. It would be interesting to measure the temp on others to make comparisons. Thanks for the question!
On your right side there I think I would have used probably a 3/8 90 You can Weld your tube straight from that to your right exhaust pipe Just FYI
Thanks James, a weldable/maleable fitting of that type would have made this easier. This project was another example of just using what we have. Thanks for the suggestion!
Terrific, thanks for this 👍 quick question, did you check if the heat riser was clear of buildup? They can get pretty blocked sometimes.
Thanks Kombi Garage. Yes- the riser was cleared when the engine was assembled a few years ago and had no opportunity to become clogged with the aftermarket exhaust. But that is correct- they do become clogged with soot over time and even worse with an improperly designed exhaust. Thanks for watching!
A 10 degree reduction in cylinder head temp???? Were you able to confirm that? If so, that’s huge!!!
Also, can you do a short on your cylinder head temp sensor/gauge? Make/model, sensor location, etc? Not really a fan of the CHT senders that sit under the spark plug…hoping you found something that maybe mounts directly to the head or fins in some way.
Yeah, that was a big dip in temps on a similar run. I'd count that as a casual observation; anything definitive would need a lot more data before/after. Either way, a better running engine is going to live a happier life!
I have a Dakota Digital CHT gauge purchased a decade ago. So far it's been great (albeit a little ugly). Unfortunately the thermocouple fits under the plug. There is a sensor boss on some of the later heads (for fuel injection?) but seems the plug area gets a more direct read. Just a hassle when dealing with plugs. Thanks for watching!
Amazing how there's no hole from the exhaust but the tab is there. Almost like the aftermarket producers don't know what they're making lol.
Seems that way GT, but I'm guessing they leave it undrilled for people running dual carbs. I'd prefer they drill the holes and provide block offs, but I guess that would raise the price a little. The good news is, we can fix it!
@@HapticGarage duel carbs wouldn't use the pre heat manifold though? That's the main thing, most things can be made to work.
@@GT.Bugger Correct- duals don't need it because they sit right on top of the heads. No chance for icing or de-atomization. I've never used duals but that's what people say and it makes sense to me. And yes, there's always a way!
Thanks!
Thanks Michael!
Make a drilling fixture that bolts to the flange
That would be a fun project Robert. A smaller drill bit (maybe 1/4") would be needed to squeeze around the bend but could be done. Thanks for watching!
Check the manifold tube. It could be clogged
Hello Joe, the manifold tube was cleaned out when the engine was assembled a few years ago but you're right, they do become clogged. Thanks for watching!
Is there a chance the heat riser is partially clogged?
That’s any problem running with the heating tube cap off ?
Hi Everton, thanks for watching. I'm not sure I understand the question but if you are asking about a heat riser block off plate, it's there to prevent an exhaust leak when the header has been drilled through. The block off plate wouldn't be necessary on an exhaust like mine where there was no hole until I drilled it myself. I'm guessing a possible reason for manufacturing them this way is so a person running dual carbs (who would not be using a heat riser) doesn't have to use block off plates. Sounds like a good excuse anyway! Good luck with your project!
Better gas mileage?
I expect so- a smooth running engine is more efficient and that means better mileage. This particular engine needs other improvements too but this is a good start.
Fake parts is that the same as fake it till ya make it....
Good one Jeff, more like "Make it so ya don't fake it"
@@HapticGarage make it so you don't break it
@@type4revolutionstudio yup, it's a neat project the first time...
Inhale that galvanized conduit.😢
Aftermarket headers come with un-drilled risers on purpose. It's easier to take metal away than put it back. People running dual carbs can leave the pipes closed up. Everyone else can drill holes. Odds are, more people own drills than welding kit.
Another thing I've heard of was to drill different sized holes on each side. With the way VW engines fire (left-left-right-right) the tiny difference in flow is enough to keep hot gasses flowing one-way. It doesn't need much to get the job done. A 3/16 on one side and 5/16 on the other fit the bill.
While what you did was far more correct, it's more work than the exhaust's designers intended.
Edit: And block-off plates leak more than un-drilled holes.
Hi Imnotgoing Sideways, thanks for the input. I agree the aftermarket manufacturers are doing it this way intentionally, and hope they would at least advise holes be drilled when a heat riser is being used with a single carb. In support of the different sized holes concept, I've seen optional restrictors used in other applications involving exhaust waste heat for whatever circumstances required them. Additionally, there are ways to improve on the original VW design but I don't feel this is one of them. I prefer this approximation of the original plumbing for its approach to high and low pressure areas that support the flow of heat through the system. And I kinda like working on my car. Thanks again for the contrast, it's a healthy thing to hear different perspectives.