d-bo

iTrader: (14)

In my quest to shave some more weight from my car and hit very low 10's maybe high 9's i am asking if it is beneficial to have an exhaust on a car, or if an open downpipe whether it be thru the hood, or exit from just under the car would in any way help the top end ; as well as it's weight benefits.

i have a buschur exhaust for the street

with exhaust removal i am suspecting my car would be around 2750-2800lbs with no driver


i was also thinking of switching to GSC S3 Cams. not sure if they would work well with my setup without changing out my whole valvtrain. i will only be revving to about 8400-8500 max

last year i was trapping 127 low 11's on 93 oct and 25psi on a standard 35r with about 400lbs more into the car on street tires with 1.8 60' . my best 60' was 1.6 on these tires so i have since switched to hoosier DR's



here's a run down of my setup as far as things that "matter" on the motor side
stock head ports. stock bottom end

STM Standard placement vband manifold
HTA86 w/ tial .82 housing
aem v1
-CompCams 272's
BC Springs & retainers
okada Plasma Coils,
Buschur Deluxe race Front mount.
2.5" ICP
tial q/tial 44
Buschur 3" Turbo Back Exhuast
Magnus V5
E85


i am going to go to the track @ 30psi which is what I am at now, see how it runs, and then make adjustments from there.

thepoint4life23

iTrader: (3)

I don't think you need a open down pipe just get better cams and you will need to rev the car out a little more.

EVOjunky

iTrader: (4)

Well, it will help. Your loosing weight and it should add some power. But it will be very minimal gains on both ends and I cant say youll see a difference in times from it. I would absolutely invest in the S3's as they would be way more beneficial then taking the exhaust off.

d-bo

iTrader: (14)

I PM'd ER about getting some cams so I think I am going to get those either way JW about the springs. I'm sure I can pick up a ton of top end.
These cams I have now were great with the stock IM, .63 housing I had before. Tons of midrange

doober

iTrader: (17)

Check into ER's test pipe dump thing. It's the best of both worlds. I run open DP with s3s right now all the time and I will tell you it is not very practical. I know some people have gotten some unreal gains by running open dump due to freeing up restrictions but I wouldn't recommend it unless you tune for it. I'm going to try to get a back to back to compare open dp vs stm's aluminum exhaust here shortly once my arm heals.

On to the weight savings.. if it's still a street car get the aluminum exhaust. It weighs 9lbs total! It's an amazing piece. Basically if I were you I would run the aluminum exhaust for weight savings and ER's test pipe dump for the power aspect. That way you could run one tune and cover your *** at all times while still having the best of both worlds.

d-bo

iTrader: (14)

Well I was more so doing no exhaust for the weight savings, if it won't hurt the car I will do it. If it helps performance that's great.
I have the buschur exhaust already and it would cost me almost 500$ to switch to the STM exhaust which I have considered but don't find worth it. If I were stock exhaust I would do it


I would imagine driving around no exhaust would be horrible lol. This will be a 1 or 2 time thing and it'll be full exhaust from there on out

doober

iTrader: (17)

Just run two maps and one for the track and the open DP and you won't regret it. I'd recommend something like a turn down to keep the heat off the underside of the car for when you do pull the exhaust though.

d-bo

iTrader: (14)

just ordered the cams and springs from STM. i saw on facebook today they were running a special on GSC products so it was perfect timing. if i didn't live in the same state i could have saved 50bucks. ended up only saving $4 because of tax but oh well lol

i will do a turn down for sure! where is ER cutout? does it replace the cat section?

doober

iTrader: (17)

http://www.shopenglishracing.com/Eng...Pipe-Dump.html

Check it out.

d-bo

iTrader: (14)

Yea that's where I figured it'd be. I'll prob dump it just passed the oil pan

Sharkbite2000

iTrader: (21)

I like.

doober

iTrader: (17)

I'm going to pull the trigger soon on it and try to see what it can do.