Need help with my exhaust solution/weight reduction

SO.....I figured I would cut the rusted catback off, yes, everything from the cat to the tips must go. I figured I could kill 4 birds with 1 stone. 1-eliminate the cat, 2-eliminate the shitty muffler 3-weight reduction and 4-eliminate the rusted exhaust.

My question is will a 2" in/out muffler restore the backpressure? Will I lose alot of torque?

Dude.... www.fierostore.com....

They have an awesome exhaust system for 250 bucks. I don't recommend trying anything else other than the Borla, but they don't make it anymore. The system backpressure is made to match stock specs. As far as weight reduction, you are on the wrong end of the car my friend. The exhaust doesn't weigh but maybe 70 pounds max. Start with the doors.

I am going to put a borla XR1 muffler on it and that ocelot is no good. As far as weight reduction goes I have started in the right place. I'll post the results after I do it. I just can't make up my mind on what size muffler to use.

This is my daily driven/street drag/street autoX car. plus the muffler only cost like $125 and the cutting and tossing of the catback is free.

how much weight are you planning on saving? I love 20 in each door, 12 under the front hood, and ~10 on the interior

I want to get it down to about 2500 I thought that the catback was a good place to start since I can't afford to get a new one and it is rusted like no other. What did you do to shave those pounds.....run and lift weights...lol :naughty:? mine has power everything. I planned on getting F1 style mirrors to replace the pwr mirrors...one day.

www.twinlakesfiero.com sells Borla cat back systems for the Fiero. Being a stainless steel system and million mile guarentee by Borla, you don't get them for free or cheap, but no where near $800.

I'll stick to my original idea. Since you guys are actually answering me i have some Q's.

1-Are there any GM or pontiac car parts that I could put on the fiero? Like shocks, seats, steering wheel. Can I put vette suspension ona fiero? I have heard of people putting sunbird seats in a fiero is this bolt on or custom?

2-Do you know where i can find a shift kit, manual valve body and a torque converter for an 85 auto fiero gt?

Go to the fierostore.com and order a catalog. Or JCWhitneys.com. THey have all that shyt for a reasonable price.

Well my original plan to get an 85 auto fell threw so
by some freak accident I ran into a guy selling an 85 4 speed.

Last night I ordered a borla xr1 oval racing muffler 2.5 in/out. I then unbolted the ENTIRE exhaust system from the y pipe back. It is very loud, which I don't care either way because the muffler comes tomorrow. I will put it on and report my findings.

Reduce weight by getting rid of extra creature comforts - Like seats and brakes :LOL:

Serious - you can lose weight by removing the spare tire well and mounting hardware if having a place to put a 35mph max doughnut spare is not high on your list. Plexiglass is better then ever nowdays so you may want to change your side windows. The windshied and rear window are important structural parts of the car so you should probably leave those safety glass.

I live In IL and my uncle owns a custom exhaust shop. I had him custom bend me a 2 or 2 1/4 inch system i cant remember what size it is but all i have is a cat and some stainless tips... sounds cool as hell but the cops dont like it

My project WAS finished and now redesigned. I didn't get the 85 4spd, but i did get an 86 fastback4 spd. I hacked the exhaust from the y pipe back had a custom j pipe made. with the borla that thing sounds sweet. I lost NOTHING I gained alot. My powerband increased by about 500-700 rpms. i can take it to about 5800rpms. just a hair in front of the 6k marker.

Because i am not the sharpest at times i had the exhaust exit the wrong spot and it melted my lower paneling and the back of my side skirt. Luckily i have an 85 as a parts car, so no biggie. Going to meineke to have a pipe bent this afternoon.

I tried several muffler shops until I found one that would work on my car that has no cat. I have the borla xr1 oval muffler mounted in the spot where the cat was and a custom bent tailpipe that shoots down right before the e-brake cable. It only took 2 tries. I am very happy with my new custom exhaust system. It sounds sweet. Now for the 88-91 honda CRX Si cold air intake (ebay) and a fiero side scoop (fiero store).


My j pipe was expanded on the muffler end to fit the 2.5 in/out and 2.5 the rest of the way. NO restrictions except the heads and manifold.

Don't try this with out the cat. Just get a muffler that is the same size as the cat and customize it after you leave the shop.

Don't try this with out the cat. Just get a muffler that is the same size as the cat and customize it after you leave the shop.


You could also tow the car there with the plates off and tell them you're building a race car. Most places will work on a car with a hacked converter if they think it's a non-street car.