Do you weld the cut off before or after the cat? I don't belive it would be illegal to put it in front of the cat, because it's for "off road use only" but I'm not sure. The only problem I might see with having it before the cat is a lack of back-pressure. Let me know what you think, thanks

 

You can put it wherever you want to. Personally, I put mine after the cat for three reasons:

1) It cuts down on the noxious fumes that drift into your car from having the exhaust exit underneath. That stuff makes me feel nauseous after a bit.

2) There's a very convienient place under the passenger side rear seat that accomodates the cutout on the intermediate pipe.

3) Easier to reach (since mine has wingnuts) than if it were before the cat (have to reach around the front wheel) or at the headers (have to jack up the car).

And as far as "legality" they don't look at "where" the bypass is. If you bypass or have a method to bypass an operational muffling system, it's illegal. I forget which state that was that I read that about... But here and a lot of places don't exactly check that kind of thing.

 

What he said....

 

you might want to check out with emisions inspection station, here in Tucson every time i go in yearly, they walk all the way around with the mirror. That would suck to have to take it out to pass the test yearly.

 

I live in Tucson too.....good thing I got my emissions done last month.

 

If u have headers, right after the headers.

 

That's where mine are. I got a pair of cable operated ones from JC Whitney. I just got them done, so I'm waiting until spring to see how bad they're going to leak. I think that I'm going to weld a flange onto them so I can cap them properly and then take the caps off during the weekend.

Since I have Hedman shorties I put them in the Y pipe for simplicity.

The long term plan is to run some short pipes off of the cutouts for some flame throwing fun.

 

Here's mine(on my Z28)If I put on e on the 'Bird it will be in the same location.

 

I found a JC Whitney cutout, that my friend had and it's the pull kind. Can I only use one at the end part of the Y-pipe or do I have to buy 2? I have a stock Y-Pipe right now.

 

Now, at the beginning of this post where it was said about the "lack of back pressure". Is that bad? Cause I just ordered one from Summit Racing and I was gonna put on b4 the cat. But, not sure what backpressure is or needed for. It gives you more HP that way doesn't it? I just don't wanna hurt my car.

 

Low backpressure can cause valve float. Everybody has their own opinion on if this causes problems or not. I've heard of people running open headers for months w/o problems. And I've heard people say a cut-out can cause problems if opend for too long, I don't really know what the truth is

 

i didn't know backpressure had anything to do with that. Im not saying your wrong, i just havent heard of that. However i still think you would have to be running at VERY high RPMS for that to happen anyways.

 

I've been told so many different things about this so if I get it backwards again, lemme know. Low backpressure = more torque Backpressure (from cat and cat-back) = more horsepower. Hopefully I didn't screw it up again, but what are you gonna do on 2 hours of sleep?

 

more back pressure = more low end torque, to an extent anyways..

just keep repeating it

i know how u feel

 

hey HM Murdock after u placed that cutout in that area of the exhaust how was the sound, was it the same, Was it a throaty or import sounding grunt?

 

I doubt you'd think it was import sounding..lol.

 

ud be suprised i've seen muscle cars withe open headers and sound like a 5 inch fartpipe on a honda.

 

i think this sounds about right , also with limited backpressure , you only want to operate in higher temps , because cold air will shock cool the headers and block , this = very bad , am i right about this