Y-pipe / catback ****** leak

[Marccus]

I installed the new Performance Plus Y-pipe for my '89. But I can't get a good seal between the ****** of the Y-pipe and the ****** of the stock cat-back system. Exhaust gases are leaking and you can hear it when I'm driving.

Also you can see soot formation on the ****** surface of the Y-pipe that "mates" to the ****** of the cat-back. I also can see water dripping from here after the system has cooled.

I'm still using the original shoulder bolts used to mate the flanges of the stock y-pipe and cat-back.

But the shoulder length is just too long, so I stacked as series of washers below the hex head of the shoulder bolt on the cat-back ****** side so you can tighten the bolt without the shoulder of the bolt hitting the y-pipe ****** thus preventing any more tightening.

I'm also using the springs between the two flanges as in the case of the stock system.

Should I just use regular bolts instead of shoulder bolts and eliminate the springs?

I am using the origninal type of stock metal gasket that came with an '89; not the new composite type which doesn't seem as well made.

I could use the new type of donut gasket. If I do, which way does the gasket go on? Does the smaller opening of the gasket face the stock cat-back or the y-pipe.

Thanks. I've been messing with this for two weeks. I keep disassembling it and reassembling it with use of different washers, bolts, etc. and not getting anywhere.

I even made a gasket out of soft annealed copper cut from 0.012" thick copper plate and then tightend the bolts so the copper gasket bends and forms around the cat-back pipe // Y-pipe gasket interface figuring that the copper would deform under the tightening pressure and then seal up gas tight the area between the mating surfaces of the Y-pipe and cat-back.

I didn't work! But maybe I need to try it again with different size gaskets.

 

[yamahaSHO]

Well, unfortunately... unless you get a flex pipe, it WILL leak. Just install a flex and your problems will be solved.

 

[BlackMagik]

I know you are not going to want to modify your new Y-pipe...but the fix that worked for me was to cut the ****** out (both the Y-pipe side and the resonator side) and weld a straight section between them. Just a suggestion...the complication comes in when you need to remove the Y-pipe at a later date, this will require you to cut the pipe free again. It's a cheap fix that worked for me, good luck!

 

[luigisho]

I wouldn't weld the pipe for just that reason. The flex pipe idea is a good one or you could just pick up a new exhaust donut and see how it goes.

 

[Marccus]

Yes, YamahaSHO, that looks nice. I've seen others with these. Where did you buy yours? SHO Shop?

The problem is that I can't weld. I've seen the slip on type where the bellows has tube stubs on each end that hav ID's equal to the OD's of exhaust tubing.

But this won't work as well since you need to use exhaust clamps and it is a kind of Micky Mouse solution.

I really wish I could buy a Borla Cat-back for my '89. they don't sell them anymore. I know I would still need to weld the flex pipe, expansion bellows/joint whatever you want to call it.

Thanks.

 

[AREA 91]

The gasket I got with my Y pipe has a flat side, and a rounded side. The flat side faces the Y pipe, the rounded edge faces the cat back. The springs go over the bolts on 1 side of the ******, not between the two. Hope this helps...

 

[yamahaSHO]

Marccus:
Yes, YamahaSHO, that looks nice. I've seen others with these. Where did you buy yours? SHO Shop?

The problem is that I can't weld. I've seen the slip on type where the bellows has tube stubs on each end that hav ID's equal to the OD's of exhaust tubing.

But this won't work as well since you need to use exhaust clamps and it is a kind of Micky Mouse solution.

I really wish I could buy a Borla Cat-back for my '89. they don't sell them anymore. I know I would still need to weld the flex pipe, expansion bellows/joint whatever you want to call it.

Thanks.

Yes, I purchasd my flex pipe from SHOshop. As far as welding, there are plenty of shops in California that will do it for you. Yes, you can get Borla for your car. The 2nd Gen exahaust will fit the first gen. The only difference is the rod shifter, you can put on 2nd Gen Borla on you car w/ cable or rod shifter. I actually have a 91 Borla on mine. I really liked the turn down tips but still had to have the exhaust for the rod shifter. If you get the 2nd Gen Borla, you will have tips that stick out and the option of puttin a rod shifter on later. Good luck!!! Also, if you are tight on money, you can get a cheaper flex pipe at a local exhaust shop.

 

[Marccus]

witsimpala:
The gasket I got with my Y pipe has a flat side, and a rounded side. The flat side faces the Y pipe, the rounded edge faces the cat back. The springs go over the bolts on 1 side of the ******, not between the two. Hope this helps...

Thanks, everything works corrrectly with the new gasket. With the original stock gasket, the shoulder bolts bottomed out if the springs weren't placed between the flanges.

I will repeat this 100 times:

I am an idiot.
I am an idiot.
I am an idiot

.
.
.
.

 

[Marccus]

yamahaSHO:

Marccus:
Yes, YamahaSHO, that looks nice. I've seen others with these. Where did you buy yours? SHO Shop?

The problem is that I can't weld. I've seen the slip on type where the bellows has tube stubs on each end that hav ID's equal to the OD's of exhaust tubing.

But this won't work as well since you need to use exhaust clamps and it is a kind of Micky Mouse solution.

I really wish I could buy a Borla Cat-back for my '89. they don't sell them anymore. I know I would still need to weld the flex pipe, expansion bellows/joint whatever you want to call it.

Thanks.

Yes, I purchasd my flex pipe from SHOshop. As far as welding, there are plenty of shops in California that will do it for you. Yes, you can get Borla for your car. The 2nd Gen exahaust will fit the first gen. The only difference is the rod shifter, you can put on 2nd Gen Borla on you car w/ cable or rod shifter. I actually have a 91 Borla on mine. I really liked the turn down tips but still had to have the exhaust for the rod shifter. If you get the 2nd Gen Borla, you will have tips that stick out and the option of puttin a rod shifter on later. Good luck!!! Also, if you are tight on money, you can get a cheaper flex pipe at a local exhaust shop.

You mean the exhaust sold currently by Borla for the '92-95' SHOs will fit the '89-91' SHOs?

I'm not sure if those year intervals are right for the Gen I and II.

Well, I'll be damned.

But you still have to cut and weld the flex pipe to the Borla unit right?

Yes, I have cable shifter, but would like to upgrade to rod shifter. But SHO Shop charges too much for rod shifter kit.

Instructions for rod shifter by Chimes (?) say you can assemble kit with things you can make yourself. But how do you do that without design dimensions and templates?

Others suggested looking for a a kit from somene letting go of a Gen II SHO. But this doesn't seem likely as the person who bought the car next surely wouldn't want it with a missing rod shifter or newly installed cable shifter.

It seems I would need to find used kit or junked Gen II SHO.

I did find junked Gen I SHO here in CA and stripped it of intake manifold, valve covers, heads, PS pump, etc.

But I haven't found a junked Gen II SHO yet.

Any recommendations on where to look for rod shifter kit or how to assemble/make parts for the kit will be appreciated.

Thanks for everything!!!!

 

[yamahaSHO]

Marccus,
Yes the Borla will fit. No matter what cat-back you have, the flex pipe will have to be welded to it. Then the cat-back/flex pipe will bolt to the y-pipe.

About the rod shifter, check up on ebay. I think one just sold for $125. Another thing to do is watch the junk yards, I have heard of someone buying it for less than $50. Once you find a rod shifter, it will bolt right up. Good luck on your search.

<small>[ March 21, 2003, 05:06 PM: Message edited by: yamahaSHO ]</small>