Like the title said is it require to get the evo tune just with an aftermarket exhaust??????
Also what is the downfall of not having it tune will there be any problem in the long run?
Will the evo perform differently if i dont get it tune? There was a post on here i found that it was better to get a tune with an intake and exhaust, but im just looking to put on an hks exhaust.

thanks in advance guys

no, but you might run a little richer as stock evo's already run a little rich from the factory

no, but a tune will make the car feel like a differnt beast...



then youll feel like its slow the 2 months down the line

^+1, and I'd give it only 1 month!

Actually about 2 weeks .



To the OP, a tune isn't required. The cat being the biggest restriction on the exhaust side, your AFRs won't be affected much by just a cat back. But like any other major mod on the car...a tune won't hurt.

As mentioned before, it's not required. you may already know that you'll get a lot more out of it with a tune. It's also been mentioned that you may run a little more rich. you can throw an intake on there too, but do some homework. they aren't all created equal for the evo. especially without a tune.

when i had my 3"TBE put on i had it dyno'd b4 and after with no changes to the tune. top end hp was same but mid range was weaker with the larger exhaust. looking at the AFR's it was about 0.9-1.0 richer on the already rich stock tune which explained the power drop, boost went about 3psi higher tho due to less restriction.

so...like a few have said, its not neccessary but you wont really be happy with it till u have it tuned...i wasn't so i did it myself and made a real difference

Thanks alot guys for all your help!!!!!!!!