Nissan 370Z Forum - View Single Post

Jordo! · 07-15-2014, 06:00 AM

I could be mistaken, but I think narrower inlets are better to maintain part throttle velocity (or the incorporation of a butterfly of some sort), whereas gradual stepping up to wider diameter as you move towards the intake manifold would be ideal for optimal cylinder filling at WOT...

I could be wrong though... worth doing a little additional research on this, but I'm pretty sure that IM and EM runner designs almost always step UP in diameter from flow entry to exit, not down.

If it's unclear, I'd keep the diameter the same, and maybe incorporate velocity stacks at the intake inlets before the MAF's.

Anyway, be prepared to do a lot of rescaling the MAF voltage tables.

Good luck!

07-15-2014, 06:00 AM	#33 (permalink)
Jordo! A True Z Fanatic Join Date: May 2010 Location: nirvana Posts: 6,394 Drives: 2023 NATM Rep Power: 418	I could be mistaken, but I think narrower inlets are better to maintain part throttle velocity (or the incorporation of a butterfly of some sort), whereas gradual stepping up to wider diameter as you move towards the intake manifold would be ideal for optimal cylinder filling at WOT... I could be wrong though... worth doing a little additional research on this, but I'm pretty sure that IM and EM runner designs almost always step UP in diameter from flow entry to exit, not down. If it's unclear, I'd keep the diameter the same, and maybe incorporate velocity stacks at the intake inlets before the MAF's. Anyway, be prepared to do a lot of rescaling the MAF voltage tables. Good luck! __________________ Enjoy it. Destroy it. Last edited by Jordo!; 07-15-2014 at 06:07 AM.