Thread: lets talk disadvantages and advantages of decat pipe

ok, it does seem that it is possible to gain like 2-4hp from stepping up from a 21/2 inch to a 3 inch on an na sr20ve. However most people on here seem to do it with a standard cat. Hell i think the budget header comparo was even done with a standard cat.

Now i have found that the cat is normally the biggest restriction in the zorst. so i am curious as to the possible power potential of running a straight through detcat pipe? Has anyone done it?

i have a highflow cat, seems to be less restrictive then the gutted stock cat i had.. its got 2.5 in/out, not exactly 3 inch lol but im sure it would help a little

no cat here. but there also aren't any emissions checks where i am in ohio.

no cats here....im a dog person ma self

will be running a 3" high flow cat with my asp's and 3" exhaust soon

I dunno. All I know is when I gutted my cat and put a 2.5" pipe in it, it seemed to pop vvl harder. It could have just been the sound though...

not the sound she just KICKS ASS

yeah i have played around with hi-flow vs gutted cats before on turbos mostly. But you are right, a good high flow cat will out perform a gutted item. This is because of the angle the air has to enter from cat back into the 3 inch (or whatever size it is) pipe.

A proper decat Pipe is best! What i mean by de-cat pipe is basically a 3 inch bit of pipe with the flanges on there

Slightly off topic, has anyone noticed a difference in sound between a gutted cat and a decat pipe? I have a gutted cat and was considering adding a resonator to reduce drone.

generally gutted cats do have more drone than a decat pipe, but muffler choice is probably the biggest factor for drone. If your cashed up and hate drone, 5zigen is the bomb for quite high flow zorst systems