Do any of guys find it pointless to run an e-cutout if you are already have a turboback exhaust? Is their really that significant of a gain between the two? Im looking to pick up the QTP down pipe soon but the only time the cutout is gonna be open is when i go to the track but i still want the 24/7 performance when im on the street.

 

QTP is not the best brand to go with. i have lots of friends that absolutely hate them. go with DMH if you are going to do it. and i have a friend with a Ecutout on his S/C IS300 and he got it because it was a cheaper alt. to getting a full exhaust

 

The cutout doesn't perform any better than a complete 3" TBE.

Cutouts have terrible reliability ratings.

Anytime you plan to drop the hammer your car will be as loud or louder with the dump.

A good 3" TBE isn't much louder than stock at partial throttle.

Unless you are running a cat the gated DP doesn't really make much sense. Why even dick with it?

 

I just did some back to back dyno testing on this exact same thing. I have a full 3" exhaust, and no cat with an open dump wastegate. Even with this free flowing setup I still picked up 13whp and about the 10lbs of torque. Seems to spool a little faster too. I was not happy withe the designs that were out there so I built my own. Works great and sounds bad *** when open. The key to the performance of a cutout is to have it as close to the turbo as possible. If it is placed properly and does not vibrate against anything you should not have any problem with false knock. I don't. This dyno chart was at low boost before we started really even tuning the car. Unofrtunatly we ran out of time and I did not have a chance to test it on the higher HP tunes. It would have been interesting to see the difference at 500whp. Nothing more fun than to crack it open and wind out first gear in a parking garage and set off 100 car alarms at the same time.

 

I have been pondering the idea of a cut out for the last month or two. But I had read that the electric motor that opens and closes the butterfly valve does not like to get dirty. So I was pondering the idea of a waste gate actuated butterfly valve. Which lead me to find this little gem:



I don't really like the 90 degree design of this piece, but it did show me that this idea is possible.

here is a link to the site:
http://www.atpturbo.com/root/releases/release091004.htm

 

EVOTECH.... on a big turbo at 500hp it probably makes a difference.....but on the stocker...... I doubt it.

I also hate the idea of super hot exhaust gas venting right under my xfer case. I have my DP wrapped all the way back to the testpipe.

 

That wastegate/cutout is a nice product. A buddy of mine has one on his turbo honda s2000, although he removed the valve from the "T pipe" and piped it something like what Evotec has going on, straight to the butterfly. It works nice, and he hasnt complained in about a year.

I have the QTP downpipe, it required a little work, but It fits perfectly, creates no false knock (in my case at least). Just had to seal the butterfly with some silicone, which you will have to do on all of them eventually anyway. I dont regret it.