Hey everyone.

I am in my garage right now currently making this setup:


It seems as if the muffler is sandwiched in between the trunk heat shield and the cradle..Is there any tips on how to get this to fit? Is the trunk heat shield necessary? I have made rough cuts on the J bends is there any tips on how to proceed?

Here are some progress pics as of now.



It also seems like the bend's radius going to the muffler is too large, yet it was the smallest (4") radius I could find..

ANY help is appreciated, I am getting frustrated and confidence is going low.

I'm not sure if this is what you're looking for, but there's one advertised on summit that has a 2.5" radius for a 2.5" exhaust pipe.

http://store.summitracing.c...738+115&autoview=sku

Since you are obviously not cutting the trunk out then those bends are going to have to be alot tighter. You are either going to have to cut that u-bend in the middle and then weld it back together with a tighter radius or they make exhaust donuts that are just as they sound. I dont remember where you can buy them but if Rickady88gt sees this then he will know where to get them at.

Eww, its so small...

3inch would gain you serious amounts of horsepower, although make it near impossible to mount with a trunk still in tact 100%.

After looking at these the pipes are too big for the radius you are looking to get,to make it easier on yourself why not just take the shape with an old clothes hanger to a custom muffler shop and have them bend it for you instead of using summit bends and it is cheaper, then you can tack it together then weld it or have them do it.

If you do have a shop do the exhaust make sure they have a mandrel pipe bender and not the usual crush bent pipe bender. The crush bent pipe sucks for flow and you really should go 3 inch into the muffler and dual 2 1/2 outs.

3" exhaust has proven to provide little back pressure for this setup

2- 1/2 into the muffler and I will be taking it down to 2 1/4 for the C6 tips.

When I talked to a couple of exhaust shops they told me how much they laugh at people who bring in clothes hanger exhausts.. the pool noodle exhaust was the most cleverest they've seen so far.

After taking my bends to a couple mandrel benders today, they clearly showed me that the bend I have is the tightest it's going to get.

Besides, how could an exhaust shop possibly build an exhaust when they don't even have the car?

Matthew

N/A

[This message has been edited by Bubbajuju (edited 07-23-2008).]

What are you swapping in? A 3800SC or 3800NA? Im just asking becuase even mildly modded 3800SC with 3.4 pulleys have been dyno proven to make more HP with a 3" downpipe opposed to a 2 1/2" Who ever told you that you cant get a tighter radius is lying to you cause heres picture proof.

This is what i was talking about when i said you could cut the U bend and make it a tighter radius

Here is the exhaust donut i was talking about which IMHO is what i would use

quote Originally posted by darkhorizon: Eww, its so small... 3inch would gain you serious amounts of horsepower, although make it near impossible to mount with a trunk still in tact 100%.

I was able to fabricate an exhaust system with a 3" exhaust U bend from the manifold into a Flotech Afterburner muffler with two 2 1/2" exhaust pipes. Works well but its is very loud at idle but acceptable at cruising speeds.

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87GT - 3800SC Series III engine, 3.4" Pulley, N* TB, LS1 MAF, Flotech Exhaust Autolite 104's Custom CAI 4T65eHD w. custom axles
87GT - 3.4L Turbocharged engine, modified TH125H
" I'M ON THE LOOSE WITHOUT THE JUICE "

quote 3" exhaust has proven to provide little back pressure for this setup

As why that is an obvious reason to use it... Backpressure kills power and fuel economy.

You will need to pie cut those bends tighter, making the effective tubing size well less than 2.5, and much closer to 2. Also, I HIGHLY suggest ditching the stock downpipe flange and going with a custom piece.

quote Originally posted by darkhorizon: As why that is an obvious reason to use it... Backpressure kills power and fuel economy. You will need to pie cut those bends tighter, making the effective tubing size well less than 2.5, and much closer to 2. Also, I HIGHLY suggest ditching the stock downpipe flange and going with a custom piece.

Unfortunantly I already have over $600 in mods to my manifolds

I have a question for everyone though, I seem to have fit it now, cutting the 180 bend with angled cuts and welding into the "kinked" bend... My question is though, can a corner of one of my exhausts touch the engine cradle??

The Poodle Noodle is a great idea. This looks like a pool item. Where can we find them.

Ted P. 3 ~ 88 Gts

quote Originally posted by daniel87fierogt: What are you swapping in? A 3800SC or 3800NA?

3800SC

quote Originally posted by daniel87fierogt:

Sweet - that is the pic of the one that I used on my 38oo SC. Spoke to Rick and they can be had here: http://store.racing-solutions.org/

--Allen

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And it begins again...

I wouldnt use that exhaust on a n/a setup... good luck breaking into 13's with that exhaust.

i used vibrant bends... they have a 2.5" with a 4" radius... not at tight as the donut but it worked for me
http://vibrantperformance.c...2d1971568f0c5a3c8a7d

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87 Fiero GT 5sp with Vortec L35 4300 Turbocharged V6
Bully Stage 2 clutch
Syclone intake manifold and engine management with Moates adapter and chip burner
Air/water intercooler and Devil's Own progressive water/alky injection
50lb injectors, 3 bar map sensor, Walboro fuel pump and Jabasco Intercooler pump
LM1 wideband on custom manifolds and 3" stainless exhaust system
T31/T04B H3 turbo and a S10 caliper conversion.
Murphy's Constant Matter will be damaged in direct proportion to its value
Murphy's Law of Thermodynamics Things get worse under pressure.
Arthur C. Clarke "Any significantly advanced technology is indistinguishable from magic"

quote Originally posted by darkhorizon: I wouldnt use that exhaust on a n/a setup... good luck breaking into 13's with that exhaust.

I dont really see any other options..the dounut looks like it sacrifices even more flow..

[This message has been edited by Matthew_Fiero (edited 07-21-2008).]

quote Originally posted by vortecfiero: i used vibrant bends... they have a 2.5" with a 4" radius... not at tight as the donut but it worked for me http://vibrantperformance.c...2d1971568f0c5a3c8a7d

This is 4" radius.. After going to 2 mandral benders They put the bend before i chopped it in half and it was in the most bended position already..

Someone on here sent a summit link, they are 3.5" radius.. reallly not that much difference, especially when its shipping date is in 3 weeks lol

Well I guess you have to either pic one or the other Either cut the bottom 1/3 of the trunk out and use nice 4-6 inch radius piping that is great for flow or keep the trunk and use the super tight more restrictive bends. But to each there own, some people will do anything to keep the trunk and some will just whack it out with out a second thought, like me

A little cutting and welding can make the bends a little tighter but the muffler is the problem as it is too wide.
The muffler I prefer is a Magnaflow part # 12158 it is more of an oval shape and fits in the allowed space easier, it still is almost touching the frame but it does fit.
Another thing to make more room is to remove the trunk exhaust shield and replace it with dynamat or some other thin reflective heat shield this gains about 1 inch across the entire trunk wall. Dan

quote Originally posted by FIEROFLYER: A little cutting and welding can make the bends a little tighter but the muffler is the problem as it is too wide. The muffler I prefer is a Magnaflow part # 12158 it is more of an oval shape and fits in the allowed space easier, it still is almost touching the frame but it does fit. Another thing to make more room is to remove the trunk exhaust shield and replace it with dynamat or some other thin reflective heat shield this gains about 1 inch across the entire trunk wall. Dan

Too bad I didn't look at that muffler first.

Good call on the heat shield,

quote Originally posted by Matthew_Fiero: Exhaust to flange Tight fit, I believe its touching cradle better view Muffler touching cradle by rear tranny mount This is how close it is to the rear heat shield.. It is also touching

mine touches the heat shield and it rattles at idle sometimes. I did hammer my muffler in a bit....


so it doesnt hit the frame anymore.

Its so sandwiched up there i could probably never get that muffler out again, for some reason there is no rattle.. I guess we'll see what happens once I hit a few bumps...

Here it is, needs a bit of tweaking, then I will clamp it to the muffler

Vroom vroom!

quote Originally posted by daniel87fierogt: Allen, I just went and looked over that entire site that you posted the link to and i couldnt find those exhaust donuts anywhere. They have just about everything but the donuts.

Call and they should have it - sorry for the delay.

Here's another that you can use also, that has it actually listed.

http://www.roadraceengineer...com/mandrelbends.htm

--Allen

I just thought of a fix for your muffler issue... I think you can leave it hitting, if you put a flex joint in where after the first 90 where it comes out of the manifolds.

Also, you MAY be better off pulling the shield out, as you will gain almost 2 inches of clearance. You will have to cut off the mounting bits on the trunk itself. Then you might just want to pull the BFH out and show the trunk who is boss.

[This message has been edited by darkhorizon (edited 07-28-2008).]

LOL, that IS a good idea about the flex line.. probably would help with stresses from my exhaust being so rigid..

That heat shield is definitely coming out, I wonder how hot the trunk will get if I leave it unprotected? hmm

It was really nice meeting you btw...

Matthew_Fiero