I have the HKS downpipe as of now. My buddy has a Helix 3" downpipe and was wondering if I'd want to trade him. I bought the HKS cause of it was suppose to keep low end, but now I have cams and a custom tune. I was just wondering if I did this if it would mess with my custom tune and if I would see any gains out of this over the smaller HKS downpipe.

 

it probably wouldnt make a big enough difference to warrant a new tune... a 3 inch DP instead of your 2.75 may lean your AFR slightly... no biggie (assuming u have plenty of safety margin in your current tune)

 

Thanks.....I mgith just post this in DynoFlash's forum and see what he says.