So I know im going to get a lot of mixed answers and no straight answer, I know that before even posting this.

If you are making 750whp / 800whp with 35-40 PSI what would be the best downpipe size to run?

I KNOW a 3" would work and has been proven but it doesn't mean it is the best size to run at the hp level.

As of right now im leaning towards a 3.5"

Let me know your thoughts!

 

i would think when you go 3" intercooler piping at that much power to also go 3.5" exhaust.

 

Not sure it will be worth the upgrade on the stock framed Black. Do you have a back pressure sensor on your current setup? It would be really good data if you decided to log it and then make a change.

 

no i dont but im going 6466 V-Band

 

Good read on your question.

https://www.evolutionm.net/forums/ev...5-exhaust.html

 

I've been wondering the same thing. I'm doubtful that I'll pick up much power though when you factor in that the exhaust is 3" and the wastegate dump is is bigger than 1.5". I hit 40-45psi just a little over 5K rpm and then the wastegate opens to hold it there. I'd love to see more comparisons though!

 

Neither a 3" or a 3.5" is going to cause any meaningful restriction at that power. 3" will work fine and be lighter. 3.5" will be louder, that's about it.