Does anyone have an opinion on this:

I have the Vortech supercharger and Neuspeed cat back. Since the Neuspeed has been shown to be somewhat restrictive, I was looking at alternatives to better exhausting WITHOUT getting rid of the Neuspeed. I'm also curious if such a cutoff were to be useful in my application, at what point in the exhaust system should it be placed - before or after the cat (ie. the cat O2 sensor)?
It's from J.C. Whitney.

 

You would want to install this device post-catalytic converter, pre-muffler. Especially if you still have the secondary 02 sensor in use. You'll probably want to install this before the Y-pipe and weld on a secondary to pipe the exhaust gasses to someplace other than under the car. No need to have a passenger side floorboard heater or a differential warmer-upper eh?

Assuming you have "tuned" the setup: flipping the bypass and switching from a somewhat restrictive exhaust to an open exhaust may lean out the fuel mixture some. You may want to test or at least consider the implications there.

However Dave, your specific application is street use: Unless Toronto law enforcement has mandatory hearing protection, you might get a bit more attention than you bargained for. But that's the idea isn't it?

 

Thanks Jerry. BTW, I'm in Calgary, but the point still holds true here. Good reminder about the lean condition. I was just thinking about it for those "odd" times it might be nice to have near zero restrictions. (Not sure when those times might be. )

 

[QUOTE]Originally posted by xviper
[B]Thanks Jerry.

 

A friend of mine had this on his old Z. Very loud, it sounded like a Harley. He called them Race Readies.

 

Definitely after the cat. If you want it to remain semi-reasonable when the cutout opens, put it after the first resonator.

UL

 

Thanks, guys!

 

Xviper


maybe this picture will help you

http://www.ultimate-racing.com/Products/El...wnPipe-US.shtml

 

I wonder how well that valve would seal. I would be concerned that it would be noisy (exhaust leak). I also wonder how much restriction it would add to the normal exhaust path.

 

S2000_Europe, thanks for the link. I like the concept of the electrically controlled valve. It's just a bit more complicated and a bit more money than I had in mind. I'd like to keep it simple.

gernby, valid concerns indeed. As for the leak possibilities, I would weld an extension pipe that would take the exhaust away from underneath the passenger compartment. As for the restriction, it has to be better than going through 2 or more muffler cannisters.

As it turns out, another board member (I'll keep his name anonymous till he wants it published) has kindly offered me his J.C. Whitney cutout for the cost of shipping. He decided not to use it. I'll do this as a fall or winter project and report on the results at that time.