ericdwong

As many of us here know, we have flex sections that tend to bust on our Y pipes, particularly aftermarket ones. I was talkin to a friend with a Integra, and he says that his car does not have a flex section but a slip joint. I recall that Stillen's Y pipe uses a slip joint I believe. I dont remember if they still use that design or not.

In any case, I'm wondering if theres a way we could utilize a different design to the flex section so it wont bust as easy. My car with a ruptured flex is gettin annoying and embaressing.

MAXINXS

I know exactly how you feel! I'm still waiting to get my flex fixed. I remember reading in a post a little while back that our cars need the flex section because of the movement the engine makes under acceleration since it is mounted sideways. The exhaust hangers don't allow it to move enough. I considered having someone just weld in a regular piece of pipe, but decided against it since I'm sure it would end up breaking. It seems inevitable that the flex joints just "fail". I too wish there was something that could be done.

DanNY

iTrader: (14)

cattman made a y-pipe w/ a slip joint..dunno what happened to that.

BriGuyMax

iTrader: (1)

welcome to the busted flex club....mine has gone twice....

Keven97SE

Cattman's original stainless ypipe used a slip joint instead of a flex. Didn't work so well. The increased vibration and stress tended to break welds. He eventually settled on the flex joint.

He already did the work for you. Flex joints work better than slip joints on our car. You could try to re-engineer the wheel, but you're almost certainly going to end up with the same result.

SLC I30t

iTrader: (1)

how long will the flex last with out implementing the duck tape to it?

he he he duck tape, a little home improvment humor.

MAXINXS

That's pretty funny! I bet we'd get a lot of members!

ericdwong

Hmm, I wonder if the stock pipe's flex section would fit. It may not be wide enough in diameter though. But yea, one thing I'm gonna look for this time is a longer flex section.

Dave B

The problems with broken flex sections is quite simple really. Take a look at a Stillen/Cattman y-pipe vs the stock y-pipe. Do you notice that the stock Y-pipe's flex is almost 2X as long? The longer flex allows for more movement and less risk of a tear, it's welds won't be torqued nearly as bad as the Stillen/Cattman flex, and less vibration is transmitted back to the motor and ultimately back into the cabin. My Stillen Y-pipe developed a leak at the flex after 2 years use. I didn't want to bother getting it fixed so I sold it to a friend who works at an auto parts store and I bought the Warpspeed non-mandrel Y-pipe. The longer lined flex has reduced vibration and noise. I couldn't be happier.

BTW, I wondering out this. Some cars with the shorter flex sections me be experiencing knock-retard simply because of the extra vibration coming back thru the motor. I know that this has happened with LT1 F-Bodies with headers/y-pipes. Just something to consider.


Dave

teejnut

iTrader: (8)

i have cattman's old y-pipe the one with the slip joint. it doesn't work every well. it was fine then all of sudden one day i was on WOT and i hear this loud sound coming from underneath my car. i figured out that the slop joint slipped out a little and started to leak. cattman says he'll put on a flex section for $100 w/ shipping to my door. not sure what i'm gonna do yet.

N1sMO

From reading all the problems with the flex section, I'm planning to get the PR motor mounts to prevent the y-pipe from flexing.

VeeTec

Well the inner part of my flex pipe came apart and blocked up the exit side of the flex pipe, with a hole, only about the size of a pea, for the exhaust to get through. It caused a major power loss.

Whatever held it in place gave, and it simply closed up.

SLC I30t

iTrader: (1)

Your motor will still move when you rev the engine. It will take more than PolyUrethane Motor mounts to get a 300lb engine to keep from gyro-shifting. You could always just weld metal links in place of the motormounts.

ericdwong

Yea then you would have vibration up the yin-yang. it was alrady bad with those PR mounts. I choose more of a compromise. As we speak, my remaining 3 stock motor mounts are receiving polyurethane filling treatment. I'll let everybody know how it turns out with all 4 urethaned. I had great results with only one done.

N1sMO

I know what you mean, but the stock motor mounts flexes like a ****. With the PR motor mounts plus a good y-pipe (warpspeed? when will it be available?!?!), I should be trouble free. I'm not too worried about the extra vibration since I've heard most of it is with the automagics.

bmfjeep

Actually there is couple of other ways to do the flex section of the Y pipe without the flex without adding a slip joint. Right after we finish the radial arms we'll do a couple of prototypes and send them out for testing. Our 2001 is coming in on Monday so we can finally finish the 5th gen Y pipes.

We did an install on a Pontiac GTP Grand Prix today and fitted it with subframes, nice looking car. The guy says it handles better, feels more stable in turns and is very pleased with how much faster he can corner.

Another car passed the old "suspension geometrics" test, (that is a joke by the way). Anyway he liked it.

Dallas

SLC I30t

iTrader: (1)

I'll donate my car 1997 I30t 5 spd, I race pretty regularly.
to the advancement of racing equipment for the 4th gen cars

nismo2020

iTrader: (1)

i took my y-pipe to a muffler shop and had them put in a new flex unit. i agree with Dave the flex sections need to be longer. otherwise i love my stillen y.

stjohnr

mind my asking?

OriginalMadMax

I've put around 40k on my slip-joint Cattman SS y-pipe. No broken welds. No complaints, other than some minor installation issues. Knock on wood, now that I've praised it ..

ericdwong

I got an email from Brian yesterday. It looks like he is researching a stronger and better flex section. But- it will most likely be several weeks before any of our pipes get fixed with the new design. In that case, I might as well put the stocker back on for the time being.

OriginalMadMax

I have the slip joint Cattman SS pipe, and I haven't had this problem. This didn't show up on a constant-velocity dyno tune either. Our exhausts are hung on pretty flexible suspensions, so even before I got the PR mounts the pipe moved pretty well with the engine.

nismo2020

iTrader: (1)

what a "slip joint" is .

OriginalMadMax

A pipe that slips over another piece of pipe.

ericdwong

This may be of some interest. I put on my stock Y pipe today. And when i had it on, I noticed that my muffler was suddenly hitting my trailer hitch. This could mean only one thing. The stock Y pipe is longer in length then the cattman Y is. This would also explain why the inner flex would "shrink" up and disattach itself from the crimping. Cause if the equilibrium point of the tail pipe assembly is further back then what the cattman Y wants to sit at, then somethin is gettin stretched. And its most likely the flex.