so i read that exhaust cutouts cain gain 12 horsepower ? i was wondering why i wouldnt just run normal exhaust all the time and what exactly do they do...do they just let all ur exhaust out prior to it going through ur cat and muffler or what?

 

Yes, they open up usually after the headers or after the ypipe, ususally before the cat(s).People put it in different locations.It's not legal to run on the street in areas with emmissions laws.

 

will it harm your engine...or make ur car sound weird...or what ? does it really help that much

 

It's not going to hurt anything, but they will make them loud...really loud...

 

^^^^
They are right on. Its going to be very very loud. If you go on youtube and check out some of the video's you can get a idea of just how loud but the positive side is you can close and open them when ever you want.

 

if you have cats, yes it would definitely give you some more power if you install it before the cats. On a car like mine without cats, it wouldnt make a whole lot of difference except make it a helluva lot louder. I personally do like the sound of them opened up though, it sounds like a nascar haha.

 

If you have a good high-flow cat (read: Magnaflow or Random Tech metallic high flow) you're only going to lose ~5HP through your cats.

 

Cutout gains are generally pretty marginal, depending on what exhaust setup you have on the car already. If you've got something that flows well, you'll see maybe 1, 2 horses outta it. If you've got stock exhaust, you MIGHT see 10 horsepower. In my opinion, having a cutout isn't that loud... I'm running true dual straight pipes with no mufflers and it's not too bad.

 

^ good point, I have Long Tubes true dual set up (x-pipe) no cats no mufflers, My exhaust is 1 giant cut out well 2 actually so a real cut out will do nothing. Cut outs work best on stock exhaust as mentioned. I also know lots of people who have LT's and use cut outs closed to have the air go through the muffler and keep the car quiet. And when they want to be noisey then they open them.

Its a cheap mod if you are never going to do anything serious with your exhaust. Otherwise , skip it

 

Thought I'd throw my 2 cents.

Cutouts are loud, but not that loud. They're loud when you're at certain RPMs. Idling is ok. At around 2000rpm your car will be struggling to breath and everything will start rattling. Why? It's not flowing with a good velocity with that giant opening. At around 3000 and up it sounds smoother. At 5000-7000 rpm it sounds like a real muscle car, it's probably the most beautiful tone my car has ever made.

The best choice? An electric cutout. Open it to impress friends, but keep it closed for the streets. That way you can keep a low profile and drive by the pigs without getting pulled over, and you get to keep your ears at the same time.

But considering at higher rpms it is actually flowing better than without cutout...would you guys say that you get some top end HP? Regardless of the cat, imagine if the cutout is after the cat.