Midpipe Questions/Problems

[BradC]

Just bought a new catless midpipe, and put that s*** on today.

I have three issues/questions, and would like to see if anyone can shed some light for me.

1. The pipe rattles like hell on my crossmember. Any ideas on how to fix?? The hangers seem firm and there is about 1/4" of clearance at the crossmember. When driving though, it rattles like hell.

2. The pipe does not seal well with the catback. I put a new OEM gasket in, and it still leaks. It looks like the pipe do not sit together perfectly flush.

3. The studs/nuts that attach it to the stock s-pipe do not clear the weld at the junction of the flange and pipe. I got that to work, but you would think the welds would have been ground better.

Any ideas on a fix for numbers one and two? The only think I could think of, is to bend the hangers to make the pipe sit higher. Not sure if that would make it rattle on the heatshield then though. Any ideas on the leak??

Thanks guys.

 

[orlandomsp]

Where did you buy the midpipe from and did you install it yourself?

 

[BradC]

Where did you buy the midpipe from and did you install it yourself?

Friend and I installed it.

dont want to say where its from just yet.

 

[orlandomsp]

Mind sending me a PM then, I'm looking to buy one right about now and I'm kind of worried about which one I should get.

 

[orng1]

What is the leak at the cat back caused by, I remember a while back a friend made a gasket out of soda cans for a ref ticket. Surprizingly it worked well, for the time it was needed. I would see about replacing the gasket, that should fix the leak. See what gasket fits best, go to an auto zone or something where they sell a bunch or buy a kit and make your own. The rattle may be from the engine moving a lot if you still don't have motor mounts, I know my exhaust would hit my bumper hard before I put them in.

 

[BradC]

What is the leak at the cat back caused by, I remember a while back a friend made a gasket out of soda cans for a ref ticket. Surprizingly it worked well, for the time it was needed. I would see about replacing the gasket, that should fix the leak. See what gasket fits best, go to an auto zone or something where they sell a bunch or buy a kit and make your own. The rattle may be from the engine moving a lot if you still don't have motor mounts, I know my exhaust would hit my bumper hard before I put them in.

Well, it has a brand-new gasket at the leak.

Front motor mount is aftermarket, and it feels much better. I dont think engine movement is making it rattle. I think either the pipe doesnt sit right, or the flex pipe is too "flexy"

 

[orng1]

Pay attention to the flange, on the stock cat back it sits at an angle. That will cause a leak when there is movement. I didn't realize it untilo after I got frustrated with it leaking every time I tapped the gas.

 

[BradC]

Pay attention to the flange, on the stock cat back it sits at an angle. That will cause a leak when there is movement. I didn't realize it untilo after I got frustrated with it leaking every time I tapped the gas.

Both flanges are angled in what looks like the same degree, but when they actually meet they arent completely flush..

 

[65racecoupe]

First thing I would do is check to see if your exhaust hangers are worn out. Then bend the midpipe hangers so you have more X-member clearance.
As for the leak, did you use new hardware?

 

[BradC]

First thing I would do is check to see if your exhaust hangers are worn out. Then bend the midpipe hangers so you have more X-member clearance.
As for the leak, did you use new hardware?

Hangers were a thought too. I will check that next.

One thing I noticed was the bracket that the stock J-pipe bolts to was completely f-ed. Good thing I put mounts in yesterday too! lol.

As far as the leak, new OEM gasket was used, yes. Also, it came without hardware, so I put in new bolts, nuts and washers, all grade 8. It sill leaks out of the top and bottom of the joint though.

 

[hotrodf1]

I used a Felpro gasket that I found in the box at O-Reilly. It "looked" like it would work and it works perfectly. It is a flange style gasket instead of the small donut stock gasket (which I could tell from the matchup of parts that it would not work).

Only problem is I didnt' keep track of what number that gasket was. i knew I woudl regret that someday. dah! Might be able to find the receipt for the gaskets perhaps . .

The SLS pipe comes really close to the crossmember - and ANY engine movement would make it hit. Remember, engine mounts still flex - even if you have the stiff ones. Dont kid yourself - you don't have solid mounts. I had to space the brace out from the crossmember with some big washers. I put one under each bolt, but it's not enough. 2 washer under each should do it, but the bolts will start to get to be short on threads. Best thing would be to get new, longer bolts and use 3 washers under each, or have some spacers made for you. I wish SLS would have included this kind of stuff, or at least instruction to tell you that you would have to do that. . . .

 

[BradC]

I used a Felpro gasket that I found in the box at O-Reilly. It "looked" like it would work and it works perfectly. It is a flange style gasket instead of the small donut stock gasket (which I could tell from the matchup of parts that it would not work).

Only problem is I didnt' keep track of what number that gasket was. i knew I woudl regret that someday. dah! Might be able to find the receipt for the gaskets perhaps . .

The SLS pipe comes really close to the crossmember - and ANY engine movement would make it hit. Remember, engine mounts still flex - even if you have the stiff ones. Dont kid yourself - you don't have solid mounts. I had to space the brace out from the crossmember with some big washers. I put one under each bolt, but it's not enough. 2 washer under each should do it, but the bolts will start to get to be short on threads. Best thing would be to get new, longer bolts and use 3 washers under each, or have some spacers made for you. I wish SLS would have included this kind of stuff, or at least instruction to tell you that you would have to do that. . . .

Cool. I was just thinking that as well, a universal 2-bolt 2.5" gasket should work, I am also going to replace my hangers. Spacing out the crossmember sucks, but if its what I gotta do...

I know the mounts aren't solid either

 

[ChopstickHero]

1. Use some 1/2" washers. I used two per bolt. this will create more room by lowering the cross member a little. I have a GTSPEC cross member (aka ladder bar), and I have no rattling with my midpipe.

2. I used the OEM donut gasket AND a universal style gasket (oval with two bolts) to seal the midpipe to catback. works great, no leaks.

 

[Lodivigo]

Sub'd, very interesting stuff. Anybody know off hand if the SLS race (non-catted) midpipe will bolt up to the Corksport J-pipe? I assume it will but then again we all know what happens when one assumes something.

 

[BradC]

Got it to work...needed some rigging to keep from rattling.

Thanks!

 

[ChopstickHero]

Sub'd, very interesting stuff. Anybody know off hand if the SLS race (non-catted) midpipe will bolt up to the Corksport J-pipe? I assume it will but then again we all know what happens when one assumes something.

yeah, technically it should if it just replaces the stock j-pipe and can mount up to the stock mid-pipe.