3 or 3 1/2 Down Pipe?
Thread Starter
Staging Lane
Joined: Sep 2018
Posts: 84
Likes: 9
From: Chicago, Il
3 or 3 1/2 Down Pipe? Wondering if it would make a difference if I went with a 3 1/2 down pipe on my 5.7? VS 7875 billet has 3’’ outlet, I saw guys at SPP on YouTube go up to 3 1/2 and was wondering am I wasting money or would this help performance? Anybody?
I'm sticking with a 3" DP for fitment at the moment. I did notice a difference in spool by changing to a full 3.5" exhaust immediately after the K member. The waste gates also recirculate back into the DP at the 3.5" pipe.
People have made 700+ on a single 3" DP, but they're probably leaving some performance on the table. If you have room, go for it. If you don't...i wouldn't sweat it.
People have made 700+ on a single 3" DP, but they're probably leaving some performance on the table. If you have room, go for it. If you don't...i wouldn't sweat it.
I'm sticking with a 3" DP for fitment at the moment. I did notice a difference in spool by changing to a full 3.5" exhaust immediately after the K member. The waste gates also recirculate back into the DP at the 3.5" pipe.
People have made 700+ on a single 3" DP, but they're probably leaving some performance on the table. If you have room, go for it. If you don't...i wouldn't sweat it.
People have made 700+ on a single 3" DP, but they're probably leaving some performance on the table. If you have room, go for it. If you don't...i wouldn't sweat it.
I agree. I wouldn’t lose sleep over it
120% of the exhaust wheel exducer diameter is the general rule of thumb for peak performance. So ideally 120% of 75mm would be 90mm or 3.5". In reality what ever you can fit is the answer. Dumps are great IMO too.
If you aren't pushing the turbo hard, can't see it mattering much.
If you aren't pushing the turbo hard, can't see it mattering much.
Last edited by Forcefed86; Jun 30, 2020 at 03:55 PM.
Thread Starter
Staging Lane
Joined: Sep 2018
Posts: 84
Likes: 9
From: Chicago, Il
Thanks to all, going 3’’ since it will be here tomorrow. Have room for bigger but it should do until I go with new setup. 99 5.7 w Stock heads & Patriot springs 600/610 238/242 Comp cam, 3:73 12 bolt T400 w 3800 stall in 3100# 81 Malibu. 750 Pro Sustem carb. Next up Gen4 5.3 w CNC 799s and turbo cam.
