question about catback exhaust size

[xXSharkfhinXx]

when i originally was looking for a cat back exhaust of course being a rookie, i just go to the website and punch in my info about being a 2015 ss camaro, 6.2l blah blah, stock blah, well it tells me while on the JBA site that if im stock headers and cats to order 40-3119 which is a catback system for my year model and type of car....so i order....i get in by ups and go to muffler guy have him install......sound is good, base sound....the only issue is when car hits bumps, lines etc in road the dam pipes bounce up against my body under the car seats...there is no clearance....i find out the stock pipes are 2.5? why would a company sell me 3 inch pipes?...how do i fix this so i dont get the bouncing of pipes under the dam car? did i have shitty muffler guy or the pipes are to big? when i get long tubes, will the long tubes(because they are a little lower coming out of the bottom of the frame?) bring the pipes down some to stay off of the body?

all i wanted was pipes lol....where did i go wrong and how do i fix this issue

[InFiD3ViL]

There are plenty of guys running a 3 inch exhaust on this car without rubbing or vibration. You probably can just loosen the clamps and do some realignment by hand.

On our cars a common point of contact with a 3 inch exhaust is our tunnel brace. The stock piece is just a flat piece of stamped metal and can be shimmed with some washers to give you as much clearance as you need, within reason. BMR also sells a really nice aftermarket tunnel brace for more clearance for like $50, if you don't want to space your stock unit, assuming that is one of your issues.

This is all fixable, so I wouldn't get too worked up. It's not a huge issue and can be fixed relatively easy. You just have to figure out exactly where it is rubbing and do some realignment. Since you paid to have this done by an exhaust shop, maybe your first step should be to communicate with them and see if they will do some realignment for free. Because this really should have been part of the install for any competent shop, in my opinion.

[xXSharkfhinXx]

Originally Posted by InFiD3ViL

There are plenty of guys running a 3 inch exhaust on this car without rubbing or vibration. You probably can just loosen the clamps and do some realignment by hand.

On our cars a common point of contact with a 3 inch exhaust is our tunnel brace. The stock piece is just a flat piece of stamped metal and can be shimmed with some washers to give you as much clearance as you need, within reason. BMR also sells a really nice aftermarket tunnel brace for more clearance for like $50, if you don't want to space your stock unit, assuming that is one of your issues.

This is all fixable, so I wouldn't get too worked up. It's not a huge issue and can be fixed relatively easy. You just have to figure out exactly where it is rubbing and do some realignment. Since you paid to have this done by an exhaust shop, maybe your first step should be to communicate with them and see if they will do some realignment for free. Because this really should have been part of the install for any competent shop, in my opinion.

they are bouncing or rubbing right at those flat silver heat insulators(underneath in middle) right under the front seats of the car, when i hit a bump or even un level lines in the road, the pipes move and hit above in that spot.....im gonna bring it to another muffler shop and see if they can realign them....so annoying. i did bring a couple of times to the original guy, he tried a couple of things that didnt work and he couldnt figure it out, so i was like screw it..u have a link to that tunnel brace ?

[GONIF]

My SW 1 7/8 long tubes and MBRP 3 inch exhaust have been on since the first month I bought the car and have been perfect ever since. No rubbing, or clearance problems what so ever. I installed them on my lift at the shop myself and they fit perfect.

[xXSharkfhinXx]

Originally Posted by GONIF

My SW 1 7/8 long tubes and MBRP 3 inch exhaust have been on since the first month I bought the car and have been perfect ever since. No rubbing, or clearance problems what so ever. I installed them on my lift at the shop myself and they fit perfect.

pics? ur catless?

[pyroguy]

The issue lies most of the time with the brace underneath the car that the exhaust runs on top of. Kits like SW's have spacers so that you can still utilize the brace but have it lower so that you don't bump your exhaust all of the time. If your kit didn't come with or the exhaust shop didn't install spacers they may have either shoved your exhaust way up into the tunnel so that it doesn't hit your brace, but might hit the floor or driveshaft, or it is bouncing off of that brace.

[xXSharkfhinXx]

Originally Posted by pyroguy

The issue lies most of the time with the brace underneath the car that the exhaust runs on top of. Kits like SW's have spacers so that you can still utilize the brace but have it lower so that you don't bump your exhaust all of the time. If your kit didn't come with or the exhaust shop didn't install spacers they may have either shoved your exhaust way up into the tunnel so that it doesn't hit your brace, but might hit the floor or driveshaft, or it is bouncing off of that brace.

sounds exactly where the pipes are tapping.....

[xXSharkfhinXx]

here is a picture

[pyroguy]

The area in red is what I'm talking about. See how there's some spacers vs. the picture you posted:

[xXSharkfhinXx]

Originally Posted by pyroguy

The area in red is what I'm talking about. See how there's some spacers vs. the picture you posted:

Attachment 1017647

so u brought the plate down with spacers so pipes wouldnt tap the bracket that crosses?

mine are going upward and tapping not downward toward the cross brace, so im not sure i need spacers unless im totally in the dark

on my pipes the tapping seems to be occuring where the pipes start to make the y toward front right under the seats or slightly between front and back seat

[Greenhornet2]

If they are angled up and hitting the floor the exhaust has to be adjusted. If it's a little low spacing that crossmember will work. Too high and you have to adjust the exhaust itself.

[pyroguy]

Originally Posted by xXSharkfhinXx

so u brought the plate down with spacers so pipes wouldnt tap the bracket that crosses?

mine are going upward and tapping not downward toward the cross brace, so im not sure i need spacers unless im totally in the dark

on my pipes the tapping seems to be occuring where the pipes start to make the y toward front right under the seats or slightly between front and back seat

Hopefully they didn't weld your exhaust in. Basically the exhaust shop installed the exhaust so that it wouldn't hit the brace which angled it up into the heat shields. With the spacers you can adjust the exhaust more straight in line which should get it off the heat shield and off the brace.

[xXSharkfhinXx]

Originally Posted by pyroguy

Hopefully they didn't weld your exhaust in. Basically the exhaust shop installed the exhaust so that it wouldn't hit the brace which angled it up into the heat shields. With the spacers you can adjust the exhaust more straight in line which should get it off the heat shield and off the brace.

i dont understand how the spacers would lower the pipes? i thought inside the red pic the spacers were on the cross bracket and were in place to lower the bracket?....

he welded parts of the cat back together but its connected to the cats with bracket cuff link looking reinforcers with screws that tighten etc....

[xXSharkfhinXx]

Originally Posted by Greenhornet2

If they are angled up and hitting the floor the exhaust has to be adjusted. If it's a little low spacing that crossmember will work. Too high and you have to adjust the exhaust itself.

you think it needs to be adjust itself closer to the cats or further back towards the cans?


im gonna have it look at soon when i put my long tubes on with hf cats in the next 3 weeks....

should i use hf cats or not cats is my new dilemma lol