andy4g63
15+ Year Contributor
- 958
- 11
- Oct 3, 2006
-
NY,
New_York
I think im just gunna make a v-band flange because i cant find one locally that will match up with my hx40 exhaust housing. Now i have to decide on what size exhaust to use. If 3" is big enough, I only need to make a new downpipe. Will 3" exhaust be too small for this size of turbo? I have some 3.5" bends, but i dont think i have enough to make the whole exhaust. I guess i could just make the 3" downpipe and hook up my backpressure gauge for a comparison. I see on the results thread that badman21 had 3" dp and 4" exhaust, but everybody else was running 3" or didnt include it in their post.
What do you guys recommend for exhaust size?
3" is more than enough. I am sure you know, that the downpipe is the most important piece of exhaust system if you are running full exhaust. The biggest gains come from larger DP install. If you could make 3.5" DP and the rest 3", you should be more than pefect. On the other note, HX-40 turbine exducer is like 62.8mm and 3 " is 76mm and about 72-73mm internal diameter, so do the math yourself.