Exhaust flex coupler for turbo build
TECH Fanatic
Joined: Dec 2019
Posts: 1,129
Likes: 478
Never used a slip or a flex for a setup where the turbo is hard mounted via T4/T6 flange directly to an exhaust manifold. Haven't had a crack or failure in years.
When using V-bands to mount a single turbo, or bracing the turbo to something other than the engine/exhaust directly, then it should be a consideration.
When using V-bands to mount a single turbo, or bracing the turbo to something other than the engine/exhaust directly, then it should be a consideration.
Are the HS kits still made of thicker piping? I had one years ago that was closer to schedule 10 thickness than the typical 16g a lot of people use. It also did not have any flex between manifold and turbo.
Also look at the Holley turbo manifolds, lots of guys are using those cast manifolds with a solid crossover without issue. I had a kit like that for awhile that use a stock drivers side manifold and solid crossover worked fine.
Also look at the Holley turbo manifolds, lots of guys are using those cast manifolds with a solid crossover without issue. I had a kit like that for awhile that use a stock drivers side manifold and solid crossover worked fine.
The T6 kit I have now looks to be even thicker material than that so I think its fine also the turbo is mounted with a pretty heavy duty bracket to the engine so the piping isn't even supporting any weight.
Never used a slip or a flex for a setup where the turbo is hard mounted via T4/T6 flange directly to an exhaust manifold. Haven't had a crack or failure in years.
When using V-bands to mount a single turbo, or bracing the turbo to something other than the engine/exhaust directly, then it should be a consideration.
When using V-bands to mount a single turbo, or bracing the turbo to something other than the engine/exhaust directly, then it should be a consideration.
Perhaps, but even some race car guys are replacing double slips with straight pipe because they failed in competition, here's a recent example: After a day or so discussing... - Rock Solid Motorsports | Facebook
It's so hard to comprehend why they had issues in that configuration
I agree, I've always seen solid mounts from OEMs but to be fair they're usually cast iron and hung right off the head/manifold and not some complex routed hotside with a huge hairdryer hanging off of it. I've seen the braided couplers from OEMs disintegrate. Hard mounted is still my preference.
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Truth, so much goes into thermal and NVH OE testing that you would never see solid pipes on this stuff. Only reason OE manufactures even use any sort of flex part is because they couldn't make it out of life test warranty period without, they clearly don't want to spend more money if they can help it. I do believe you guys that say you get by with zero failures hard mounted, but you simply don't put the miles/hrs on the parts to fully see the failures. Also consider some of the flex options that you see failing are not always up to OE standards as far as material, placement or quality.
Thread Starter
Joined: Apr 2007
Posts: 9,711
Likes: 999
From: Evansville,IN
You guys are talking about using flex couplers on the hot side right? Between the manifolds and turbo?
I don't know if it will make a difference, but I'm wanting to put the coupler AFTER the turbo before the flowmaster merge in the y pipe. I wouldn't think there would be as much heat if they were between the manifold and turbo but I could be wrong.
My turbo kit is the APS style kit from Huron speed. The downpipes exit in the same place as long tube headers would.
I ended up getting the flex coupler I posted and some v band's. If it fails I will return and post about it.
I don't know if it will make a difference, but I'm wanting to put the coupler AFTER the turbo before the flowmaster merge in the y pipe. I wouldn't think there would be as much heat if they were between the manifold and turbo but I could be wrong.
My turbo kit is the APS style kit from Huron speed. The downpipes exit in the same place as long tube headers would.
I ended up getting the flex coupler I posted and some v band's. If it fails I will return and post about it.
TECH Addict
Joined: Oct 2016
Posts: 2,513
Likes: 480
From: PDX-OR-USA
I use them on setups where the distance between the pipes leaves little room to expand, like a Y-tube that has to cross under the engine to join up with the passenger side.. Plus its a jeep so off road you need the exhaust to have some give or it will crack at every weld eventually.. The entire factory system failed twice on mine in the first 60K.
When they did the 3rd one I convinced them to add a bellows in the cross over from driver to passenger side and it cured the problem.
When they did the 3rd one I convinced them to add a bellows in the cross over from driver to passenger side and it cured the problem.
You guys are talking about using flex couplers on the hot side right? Between the manifolds and turbo?
I don't know if it will make a difference, but I'm wanting to put the coupler AFTER the turbo before the flowmaster merge in the y pipe. I wouldn't think there would be as much heat if they were between the manifold and turbo but I could be wrong.
My turbo kit is the APS style kit from Huron speed. The downpipes exit in the same place as long tube headers would.
I ended up getting the flex coupler I posted and some v band's. If it fails I will return and post about it.
I don't know if it will make a difference, but I'm wanting to put the coupler AFTER the turbo before the flowmaster merge in the y pipe. I wouldn't think there would be as much heat if they were between the manifold and turbo but I could be wrong.
My turbo kit is the APS style kit from Huron speed. The downpipes exit in the same place as long tube headers would.
I ended up getting the flex coupler I posted and some v band's. If it fails I will return and post about it.
TECH Enthusiast
Joined: Dec 2017
Posts: 676
Likes: 72
I actually have used a small stainless flex that cat uses between the exhaust side of there compounds on the acert c15. It last for a mill miles on the big trucks and the compounds run pretty high exhaust Temps. I used it on my single set up and got 30k on it and it looked brand new when I took it off to move to my present set up I'm fabricating. I admit I used it cause it was free so there is that. Not sure how much one costs if you where going to buy it but I'll check and let you know.
I actually have used a small stainless flex that cat uses between the exhaust side of there compounds on the acert c15. It last for a mill miles on the big trucks and the compounds run pretty high exhaust Temps. I used it on my single set up and got 30k on it and it looked brand new when I took it off to move to my present set up I'm fabricating. I admit I used it cause it was free so there is that. Not sure how much one costs if you where going to buy it but I'll check and let you know.
interesting. I’ve built about 30 kits with these types and haven’t encountered an issue outside of the braided part.
Even the bellows posted above backpressure has made them expand and those are a good bit stiffer than the braided joints but at least with overlapping pipes inside they don't typically blow out or send pieces into the turbo. So now I prefer solid mounting if I can, haven't had any issues with that.