WICKED SS

iTrader: (36)

I have been thinking of changing my exhaust set up so the cops stop following me everywhere. I was thinking of putting a stock or quiet flowmaster cat back instead of the loudmouth I have plus run 2 electric cut outs, one where each cat is supposed to be. Or run one cut out in the I-pipe, not sure what would perform better? If anyone has pictures or sound clips could you post them.

question
#1 would I gain a little more power running dual open cut outs compared to my orp and loudmouth?

#2 How do you like these electric cut outs, any problems?

#3 What gains did you see in hp and tq?

WICKED SS

iTrader: (36)

TTT

2K2CamaroSS

iTrader: (18)

QTP makes a Y-pipe for Hooker/Jethot headers that has two electric cut outs on it.

Here's a pic of it

WICKED SS

iTrader: (36)

Thats exactly what I was thinking about, just wondering if 2 cut outs will make more power then 1 cut out further back in the I-pipe?

Colonel

No, not so unless you're running about 500 RWHP or better.

BigPlanTransAm

what about if you have a qtp style electric cutout where the actual hole is about 1/2" smaller than the rest of the exhaust? im talking about how the butterfly part has to be able to move inside the pipe so naturally it has to be smaller. mine doesnt let all of the exhaust out the cutout. some still goes through the muffler and you can tell by putting your hand behind the pipe and feel the exhaust coming out.

WICKED SS

iTrader: (36)

Forgot to add this will be on a 500+rwhp H/C car running 100-150 wet shot. Will it matter much?

Colonel

If the y-pipe and the cuttout are both 3.5", then it'll flow fine for that. But, for that kind of power I might go with the dual cuttouts instead...just to get every last HP out of it.

BuckeyeROC

iTrader: (7)

I think you'll gain more w/ 2 cutouts at your power level. I gained about 25 HP with just one 3" cutout on my IROC, went from 12.39 @ 109.5 MPH to 12.17 @ 111.93 MPH.

00z

you think the qtp y pipe will work with pacesetters? also, do you get bad exhaust leak from the cut outs?

WICKED SS

iTrader: (36)

I have decided to go with 1 cut out in the I-pipe and see what happens. I wish I had a 3" y-pipe but its the 2.5 ORP that came with my Mac headers. I talked to a company which told me this

" What I would recommend is putting 1 in the I-pipe. The benefit you get is having the opposite side exhaust pulse help pull the one coming out the cylinder. Since the engine is really cross firing, you lose that benefit when you decouple the exhaust pipes and dump each one individually. Thus, you'll lose a bit of scavenging."

BuckeyeROC nice gain where is it located? So you gain 25 hp over a stock exhuast set up or flowmaster catback?

Colonel

"I wish I had a 3" y-pipe but its the 2.5 ORP that came with my Mac headers."

Big mistake. That 2.5" Y is going to cost you some serious HP. Trust me, I've dyno tested this at MTI. 2.5" is way to small for 500 RWHP. If you're going to run the 2.5" Y, then I would definitely go with two cuttouts before the 2.5" begins.

Colonel

BTW, you'de be best off with some bigger headers for that kind of power too. 1 3/4" is kinda smallish for 500 RWHP. 1 7/8" would be better.

Z-Rated

Colonel, when do you think its time to go up too 1 7/8?

Nickn20

this is the setup im running, I dumped the FLPs right away, got some 1-7/8s QTP headers, 3 inch y-pipe to my 4 inch catback with dual 3 inch cutouts, and im changing the blowmaster muffler to something different i dont think anyone here has ever heard or seen, should be interesting.


as for the cutouts, yes the butterfly is approximately 1/4 inch smaller, so dual 2.75 inch cutouts, pretty much, but hey the rest of it escapes the catback if it pressurizes at all. I cant wait to see what it does! 500+ rwhp on motor is what im hoping for.

Colonel

"Colonel, when do you think its time to go up too 1 7/8?"

Depends on how serious you are about extracting every last HP and on how well you're going to keep the RPMs out of the cellar. Me? If it's my track car we're talking about, I'd run 1 7/8" at 450 RWHP. That may be a little premature in some people's eyes but...it's NOT going to hurt top end power and on a track car with a loose converter, you're not going to see the low-end or mid-range anyway.

WICKED SS

iTrader: (36)

How much hp and tq did you gain when comparing? I thought about getting some other headers but I am on a tight budget.
Say if I were to run that 3" cut out in the I-pipe with the mods in my sig plus S2 GTP 5.7 heads with 10.9.1 compression you dont think I will make around 440-450rwhp on motor? I made the numbers in my sig without real tuning only lean it out by 6% with the Maf Translator so I know I could have made 400+rwhp. And if I were to run 2 cut outs, you think I would make more then that? I was told I would lose some bottom end power with 2 in the y-pipe?

Man all these exhaust set ups is driving me crazy

stevez28

I also wanna know if the QTP dual elec. cutout y-pipe will work with the Pacesetters? Anyone know????

00z

since noone has probably done this. i'm thinking it may. i think i heard someone say pacesetter are hooker knock offs so they should have the same demensions so it might fit. when my pacesetters come in im going to measure them and call qtp to see if it will work.