Exhaust Cut-out [Merged 8-9] cut out bypass

[imptuner]

to me cutouts seam like they would make alot of power when open but be more restrictive then just the muffler when closed. it seams like with that angle it would go down and then have to come back up the exhaust a lil it seams like it would be a bad thing but its just theory in my head

 

[TSIsean]

A friend of mine has that QTEC cutout. It works pretty well, when it works. He had to send it back 2 times because the electronic opener kept breaking.

 

[ProStreetOnline]

The testpipe would be the easiest place to put it, but the "best" place would be where the downpipe bends. You would put it in a place so that when the QT cutout is open, the exhaust gases have a straight shot, instead of bending first.

The horsepower gains might be minimal as compared to the testpipe, but it might not fit anywhere otherwise....

 

[tighty]

I'd have to agree that on the front of the pipe would be best if you can get someone to weld it on there for you that way. I have mine where the cat used to be a its a tight fit.

 

[GSX_Dan]

I have it on the test pipe also it just hangs quite low to the ground and is almost hitting the floor of the car. Definitely the lowest point of the car and you have to watch out not to hit the motor or you can kill it (found out the hard way).

Best location for it would be right around the first bend in the DP but it can prove quite difficult to get it located there. If anyone has any success let us know.

 

[GSXlaunch]

Best location for it would be right around the first bend in the DP but it can prove quite difficult to get it located there. If anyone has any success let us know.

That is where I am going to get it mounted...one way or the other. I will post pics and updates...thanks

hmmm, thinking further about this location wouldnt this location add to the risk of fire? I am sure if its that close to the turbo, flames will no doubt be shooting out...especially with C16 race fuel. Oh well, I am gonna try it...I wonder how loud the turbo will be with it fully open.

 

[tighty]

Loud?

2 Words...

Tractor power.

 

[1FAST2G]

I have my electric cutout on the first bend of the downpipe. One big problem your going to have is boost creep. My car was fine with a 35mm tial on the exhaust manifold with a 3" exhaust, but with the cut out there it would creep no matter what I set it at. It would go from 12psi to 26psi. I had to add another 35mm tial to my exhaust manifold. So now I have one on the number 1 runner and number 4 runner. This cured all my boost creep. So just be ready for this cause it will be a very free flowing exhaust and it will be harder to control your boost.

 

[GSXlaunch]

I have my electric cutout on the first bend of the downpipe. One big problem your going to have is boost creep. My car was fine with a 35mm tial on the exhaust manifold with a 3" exhaust, but with the cut out there it would creep no matter what I set it at. It would go from 12psi to 26psi. I had to add another 35mm tial to my exhaust manifold. So now I have one on the number 1 runner and number 4 runner. This cured all my boost creep. So just be ready for this cause it will be a very free flowing exhaust and it will be harder to control your boost.

Good point...I cant afford too much boost creep with this turbo. I may have to rethink the location now...

 

[1fast97gsx]

Mine is on the downpipe right before the cat.

 

[killab443]

THis forum might be older then my dog but I thought of something interesting on the QTP cutout. I checked the downpipes out that QTP makes and they show that the cutouts are closer to the beginning of the cat. Now on the VW DP there is an exception cuz it looks the downpipe conection is at the bottom of the the engine and the cat is not far behind so there is not much room to put the cutout. But maybe farther down the exhaust may be better for the cutout, similar to the WRX cutout they sell. Check it out yourselfs at http://www.quicktimeperformance.com/ and let me know what you think.

 

[91-gsx]

this is an old thread but a really great topic, i say you get the cut out right at the first bend so that you are basically running open o2 housing, or about 5-7" of piping-which is nothing. i am going to do this soon just like they have it pictured for the VW. i think my gains will be great becuase the exhaust i have right now sucks as far as performance goes. remember less piping equals faster spool up, the turbo does not have to work as hard to spool-so in turn colder air outlets on the turbo, and plus you get no 0 bends right there except for the o2 housing, one 90 degree bend is enough, right? here is the pic anyway:

 

[killab443]

I suposed your correct about it being better to be closer. I ran open O2 today with stock boost and the car was so much faster, cant wait to get it all buttoned up with the cutout

 

[91-gsx]

how much boost creep did you get though? what type of turbo do you have, stock 14b right?

 

[szewczyd]

So they don't make one of those systems for are cars? Anyone else have something similar to it for our cars. I am always getting in trouble with the cops for loud exhaust and really need a fix!!!

 

[FourG63 97GST]

this is creep with the cutout closed right?

 

[91-gsx]

the only thing i worry about is too much boost creep, a little i do not mind. but it is like running open o2, must have a lot of creep.

 

[WatchItExplode]

O2 dump and lots of porting (if you have an internally gated turbo) would definately be needed, maybe an upgraded wastegate flap too. Even with all that, I bet it would still creep. I sure would like to know how all of you guys with cut-outs are getting around that problem.

 

[tighty]

O2 dump and lots of porting (if you have an internally gated turbo) would definately be needed, maybe an upgraded wastegate flap too. Even with all that, I bet it would still creep. I sure would like to know how all of you guys with cut-outs are getting around that problem.

Still using the stock T25 is how =).

 

[noz]

Still using the stock T25 is how =).

Haha, that's true.
But try with a 16g, bet it will creep.

 

[selmerguy]

has anyone put a cutout on a turbo 420a? i ordered one from summit and when i have the money i will make it an electric cutout but for now i will just use the plate. where do you think i should put it in the exhaust? i was thinking before the cat. will that mess up the way my car runs?

 

[dr1665]

It's been done. You can set it up with a thottle cable to manually open/close it, an electric motor, or even a boost referenced solenoid of some sort that will open it when boost hits a certain point. I think I like the mechanical set up best. Less parts to break and I don't think I would use it that often, so...

I think I would mount it before the cat for sure. Possibly on the end of the header.

 

[1fast97gsx]

No different than a cutout on any other car would be unless its before an O2 sensor. Not a big deal, if need be the sensor can be simulated.

 

[selmerguy]

yeah i will gey one of hose butterfly electric plates. i will mount the dump pipe before the cat. do you guys think it will mess up the rear o2 sensor? does the rear o2 sensor do anything?

 

[usmusclekiller]

i have one and it hasnt set off any codes or anything. All the exhaust doesnt go out the cut out and I think as long as the rear o2 gets a little whiff of fumes its fine.