I was thinking about going with a 3" exh. cutout.

But I had some questions.

How are they installed?

Do they go before the cat?

Can we use a cat?

Which model are you using(if you own one) and why?

I am currently eliminated my Cat with a 63mm TP, and I hate the smell. I was thinking that with the cutout I can have the best of both worlds(performance/no smell)

I really like the SP racing 3" exh cutout and the ATP 3" cutout because they are boost controled/actuator.



The only obsticle is that both manufactuers are out of stock but they seem simple enough to make, maybe we can have a local vendor/shop make them for us. Unless someone has one to sell me.

thanks,

-Lu

 

You have a greddy turbo kit? If u do than you will boost creep with a cutout

 

put a HFC and be done with it

 

Check out Sarek's build. He utilizes one and it turned out great.

https://www.s2ki.com/forums/index.php?showtopic=692309

 

^^ i know, but i figured maybe someone might have other information they might want to share.

 

Yes you do install precat, If I was going to do this I would probably just make a test pipe out of the Y-Pipe and a pup or spool cat.

I have not been able to find a vacuum actuated dump anywhere but Sound Performance or ATP I though Sound Performance had theirs in stock though? I would stick with a vacuum actuated vs the electric. All of them that I have seen are a bit slow to respond.

The real trick is going to be setting it up and tuning. Are you going to be able to stand the 3-5 PSI open all the time? If not then you and install a MBC in the line to the actuator an raise the set pressure. Or you can always use a solenoid and switched input to the Emanage with (2) tunes.

 

It cant be installed before before a cat I dont think. It has to go where the test pipe is.
I just got mine put on. The setup is header to testpipe and electric cutout welded on to the tp. if your going to go with a 3 inch cutout your gonna need a 70mm tp.
Mine is getting tuned on saturday. I will post pics and vids on my guess the whp thread.

 

Im a huge proponent of cutouts, i've had one in multiple locations for a couple years now on my turbo setups.

I had the cutout in place of the cat converter on my first setup. Doing it this way, you will need to do some exhaust fab work to get the Y pipe in place properly and mate with the flanges, but you can keep your factory cat back exhaust, with the cutout in between the downpipe. Just like a test pipe, but much better...see this (with pictures)


I use a custom circuit and microcontroller to open the cutout either with a switch, or when i go full throttle. This responds quicker than boost activated, as it opens as soon as I hit 80% throttle, no waiting for boost to build before opening. It still takes ~3 seconds to open fully, but i'm trying to find a linear actuator to snap it open in a few miliseconds

My second setup i upgraded manifolds to a 'sidewinder' style so the down pipe route has changed.
For this setup, the down pipe goes vertically at the firewall and the cutout is placed at the bottom for optimal flow. That is to say, the air does not have to divert to exit the cutout.

I used a Y pipe to create the cutout attachment point, as I didn't have the equipment to cut a section of pipe on the 90 degree for the cutout to mount to. The other part of the Y pipe goes to the stock mufflers.

Hope that makes sense.

 

you most likely will BOOST CREEP so no you won't be able to use the cutout.

All you other guys have different kits. The internal wastegate on the greddy sucks with dealing with boost creep. You need some amount of back pressure.