Noob alert! Up pipe cat gutting question
 

Hi all.
I have a totally stock 05 GT. two questions for you:

Would pulling the cat from the up pipe provide any performance gain if I leave the down pipe alone?

Would the car need a tune after the up pipe is de-catted?

Thanks!

No performance gains from a catless uppipe, just reliability gains. No tune needed for uppipe change.

Some say slightly quicker spool, but I think that's all anecdotal.

as others have said you wont need a tune if you are gutting your cat. Make certain you get all bits and pieces of your cat out so your turbo doesn't suck anything up. For me it was easier to just have an sti UP on hand to swap out. Doing that you would need the resistor mod for your exhaust temp probe.

My catless UP lets my turbo spool up an entire 1 RPM faster than stock, so if that's not proof, I don't know what is.

Hey, 1 rpm is indeed slightly faster

Hmmm... 1 RPM or just add a "Sticker" of your choice, decisions, decisions... I would recommend just buying a catless UP from one of the vendors or a "Pre-enjoyed" STI or 07+ LGT up, have it on hand with new gaskets, allot of work removing the UP, gutting and replacing same. The reason one would want to remove the catted UP is because they are known to fragment and explode the turbo.

Mac

Don't gut - waste of time. Spend the $50 on an STI pipe or get a Grimmspeed or TurboXS for about $170.

Install is a pain in the @$!!!

Just be warned, lol. :hide:

Isn't it just as easy to say "don't buy, waste of time. Just gut for free?" It's tough to make sure all the particles are out but it's only the cost of gaskets.

Just buy an aftermarket up. A gutted up still won't flow as well as a aftermarket up. Even the STi catless up doesn't flow as well as an aftermarket up.

proof?

who the F cares? OP said totally stock so he won't notice even the slightest difference.

your tone suggests you care

did you happen to notice who performed those tests? c'mon man

Could be that they made a good product and they're so proud of it that they showed off with tests. I'm just saying that on a stock LGT, nobody will notice the difference in flow.