[RedBPU97]

Hello Ryan how are you doing? I was wondering if there is a significant difference between a 3.5 in dp and a 4 in dp, I have seen the results for downpipes from 3 to 4 inch but not from 3.5 to 4 in. I am a little confused because some companys tell me itll make a big difference and some companys tell me itll make little to no more power at all compared to a 3.5 dp. This will be going on a RPS Manifold with a pretty big turbo, eventually a HKS Titanium or your 4 in exhaust, but I have a Apexi N1 now, before I spend 400 more dollars for half an inch more on a downpipe I want to know hat my investment is worthwhile, let me know Ryan, thanx

 

[WOTM]

Going from 3.5 to 4in on any turbo making 850rwhp or less won't make much difference. There will be some gains on cars making more power than that but not nearly as much as going from 3 to 4. If you want to make big power 900-1000rwhp or more I would definitely go with 4in, otherwise 3.5in will suffice. Most companies are skipping 3.5in now and offering either 3 or 4.

 

[RedBPU97]

oh ok well i was looking more into the 4 inch dp since i know even though i have a big single now ill probably go even bigger later on. Youll be hearing from me in a month or so since your the only guy i know of who makes 4 in dp/mp for the rps manifold, thanx ryan

 

[WOTM]

Sounds good. Thanks!