exhaust cut out valve/valves

[sweed88]

i was wondering if anyone has put a cut out valve on there exhaust system and how it worked. i was thinking about putting 2 2" cut out valves on a warpspeed y pipe, placing them equally distant from the manifold. how do you think this would work?

[jltibbs]

Are you talking about the ones that you can remove the plates to run open headers on the track?

[sweed88]

yes but i was going to go with the electric ones. the smallest one they have is 2.5 inch so ill flare the pipe out to 2.5 for the valve then brignt it back down to 2.0 inch before it meets the collector

[MinisterofDOOM]

I'm probably going to do this with the Q at some point.

There are electronic switchers of various types. Some of them use a butterfly valve and just open up a new passage. But the better ones actually close off one passage and open the other.

Due to the Maxima's transverse setup and the way the exhaust is routed, you'll probably want to run a single electric switcher right after the y-pipe. What do you plan on doing with the exhaust plumbing AFTER the switcher? Run straight pipes all the way to the back, or run a discrete pipe to the side somewhere behind the front tires?

[sweed88]

i would like to use 2 keeping each cut out valve equally distant from the manifold. from there i would run 2 pipes again equall length to the side of the car keeping them ashort as possible. angleing them down toward the ground with a slight bend. i would just leave the cutouts on without any additionall piping but don't want flames shooting under my car.

[THT]

i would like to use 2 keeping each cut out valve equally distant from the manifold. from there i would run 2 pipes again equall length to the side of the car keeping them ashort as possible. angleing them down toward the ground with a slight bend. i would just leave the cutouts on without any additionall piping but don't want flames shooting under my car.

So the cut outs would be in the portion of the downpipe directly connected to the headers and before the first bend? Unless you're boosted, I don't see why you'd need that but it's your money and car.

[jltibbs]

It's the same thing as running open header. This is a popular thing to do on the track to make more flow. You do lose some back pressure, but that's not too big of a deal in 1/8th.

[lightsout]

I wanted the same thing about 8 months ago, but decided to wait until a supercharger was installed. When you do this MOD, take a lot of pics!!

[AcMav]

Just some questions/concerns,

Sweed what kind of racing are you looking at? If you're doing anything other than drag I might be concerned about the additional heat your adding to the engine compartment by stringing exhaust tubing under the hood. Consider using thermal coating on all your pipes so you dont suffer heatsoak which could kill your gains, or yet worse end up melting something important.

Does anyone know the legality of a system like this? I'd think if a cop pulled you over with a system like this installed you could be facing some hefty fines for environmental infractions, To be legal i'd guess something like this would have to be mounted behind the cats?

[MinisterofDOOM]

Legality depends entirely upon local laws. You'd have to check where you live to be sure.

[flyboy367]

ok first off dont do it, its not really worth it on this motor unless heavily boosted. even on my supercharged gtp i ran one and it didnt help as much as it hurt. the switch is touchy and the plate opens up all the time. the leaks sound like crap. do yourself a favor and get a quality exhaust you will do better overall. what do you have done to your car?

ps im not pulling my info out my ***, had quite a few race/street cars.