Xeryus

Hello all,
I recently had my new motor put into the car. Details are below. For now, I'm running stock exhaust... well, flowmaster mufflers, but stock headers and cats. I plan on going turbo (Hellion) so I don't want to buy exhaust components twice.

Am I risking damaging my new engine with the stock, restrictive exhaust? Burn up valves? Too much backpressure?

I plan on doing the trans and rear end before I put in the turbo, so it will be a year or 2 before the turbo comes in.

1991 LX
DART 302 block
347 stroker kit (w/ 20cc dished pistons)
AFR 185 heads (w/ upgraded valves, 72cc chambers)
Holley Systemax intake manifold
70mm throttle body
65mm(i think) MAF
custom Jay Allen turbo cam
... there are obviously many more parts, but this gives you an idea of the engine

Thoughts, comments?

1BIGMOFO

I dont think its a good idea to run stock manifolds and cats. Buy a cheap set of used shorties and an H pipe then sell them when you get your setup. I will sell you a set of MAC shorties and a MAC off road H. PM me an offer..

Xeryus

Yeah, I'm considering getting a used set of BBK shortys. I have an off-road H-pipe already but it made my car run rich when I had the h-pipe on the stock motor. Plus, in BC we have emissions to deal with, which is why I'm keeping the stock cats on for now.

Thanks for the offer, but with shipping to Canada and Customs duties, it would be cheaper to get a set locally.

1BIGMOFO

it was worth a try.. Im about 2 hours south of Montreal. where abouts in Canada are you?

Xeryus

I'm in Vancouver, BC. As far west as you can go; bottom left corner of Canada. 2 hours north of Seattle, WA.

ponyboy88

an idea would be buy the cheap headers (BBK being a prime example) and get those on, the motor will like it.

If you want, when inspection time is over and the cars got a nice little sticker, swap in the off road h. also will be liked. Most studies show that most power gains are in the header/mid pipe area and the cat back exhaust is for sound...but little power gain.

woodsy

The only thing stock exhaust will do is choke it

Portmaster

1 3/4 longtubes, 4 High flow Cats drop the mufflers. Hookers already have the o2 bungs welded in

jkrum10238

+1 i agree with port master

AdderMk2

How do you know this is true? just because you could smell more fumes?

you do realize that you had removed the cats, and eliminated their emission filtering abilities... right?

removing cats doesnt make a car run rich... it just smells like it b/c the unspent fuel mix isnt being burned up in the exhaust anymore