Exhaust Cutout

[NateS]

I have been wanting one for many months now. My money I have now is going to other more important things at the moment but, I was wondering if anyone else has one or has considered one. I know most people just go with a test pipe and all but, I want to be different. I think is would sound bad ass and would deffinatly allow for better airflow if I install it in right after the DP. I would rather not dump all this exhaust right beneath my feet but, I am trying to decide a route where I could run a pipe towards the side of my car. Any thoughts or suggestions?

[kjewer1]

I have been struggling with this topic for years. I need to find some way to get the flow of a 3" exhaust without the Masshole cops riding me for it.

The main problems I see with the cutouts are the electric motors failing frequently and the plates not sealing over time. ATP offers a unit that is boost actuated, with a modified wastegate actuator. This is old school well proven technology, and is the way I would go with it. Should also seal well, since you have the WGA spring pulling the plate closed hard. It starts to open at 3 psi, and is fully open by 6 psi, according to an email I have from them. Plus you can put a solenoid (like an old boost or fuel pressure solenoid) and a switch on it to disable it if you want to remain in stealth mode even at WOT. The ATP unit isn't cheap though, its a good 250 bucks all said and done IIRC. It also uses V band clamps, which is very slick.

I've thought of another use for that ATP unit though. I might just order everything up and try it this week, I'm getting awefully bored.

[crunchymilk55]

Also keep in mind that if you just wanted the cut-out for weekends or whatever, it takes about 15 minutes to unbolt the catback and bolt it back on at the opposite ends. It's kind of hard to explain over the net, but you basically bolt the left end of the catback to the right end of the downpipe. Instant open downpipe. I've done this before just for fun, and it gets annoying eventually. It is so fucking loud, even just cruising. But, then again, it takes about 10 minutes to put it back together too, so it's no biggie. No need for a cutout, but if you really wanted one, the one kevin talked about seems very cool.

[NateS]

Yeah, I have thougth about doing something like that before too haha. Unfortunatly my cat does not bolt up to my downpipe it clamps so even if I was to get a test pipe I would have to get flanges put on my exhaust. I would rather go with an electronic cutout or something like kevin explained. I would want to be able to flick a switch when I see a cop coming up in the distance haha. I looked at both setups on summit. They have the ones where you physically have to bolt/unbolt and then the electronic ones. I think I may have to look into the one kevin is talking about. The only question I have is would you run it straight out of the cutoff or would you attach any sort of piping on it to direct it away from the car. I guess with the setup kevin just explained there would probably be no need for the pipeing because it would open up while you are boosting so you probably wouldn't be sitting still.

[crunchymilk55]

fyi I didn't have any problem with fumes or anything. I just always had the windows down as much as possible with an open downpipe. When sitting still, you will smell it though, not to mention it will backfire a lot more and you'll hear and "feel" the popping. Overall, I wouldn't recommend it though, after a while it is just too loud. I was dying to bolt the cat back in its place. It's fun for a while, but eventually you'll just drive with it closed 99% of the time. Money gets wasted.

[kjewer1]

That's why it's nice to have it on a switch, or even better, boost actuated. I ordered all the parts to build my contraption. I'll let you guys know if my idea works, and how the part from ATP works, though there is information on that available on the EVO forums IIRC.

Another thing regarding the boost actuated cutout, in adition to using a solenoid to disable it, you could also use a spare MBC to delay it's opening. On small turbos that build 5-10 psi just climbing a small hill, this could be desireable.

[crunchymilk55]

Originally Posted by 95 GSXracer

That's why it's nice to have it on a switch, or even better, boost actuated. I ordered all the parts to build my contraption. I'll let you guys know if my idea works, and how the part from ATP works, though there is information on that available on the EVO forums IIRC.

Another thing regarding the boost actuated cutout, in adition to using a solenoid to disable it, you could also use a spare MBC to delay it's opening. On small turbos that build 5-10 psi just climbing a small hill, this could be desireable.

You calling mah turbo small ??

[kjewer1]

LMAO, that smiley is hardcore.

Hey, my turbo is small too. It builds boost if I just think about giving it some throttle.

[crunchymilk55]

you have offended my turbo. Now you will have to give me that T67 to make up for it.

true story