SU manifold flow rates

[Riceburner]

Does anyone have an idea as to how well the factory SU manifold flows?

 

I’m toying with the idea of pulling the six FCR41’s and installing two of them onto an SU manifold after porting it, with a stock air box and the yoshi dual trumpets. Not sure what power losses I’ll have, if any?

[gav240z]

My guess is not very well. Apparently there is a difference between early manifolds and later ones.

Why do you want to make the switch?

[24 Dat]

From memory i remember seeing some data that of the factory inlet manifolds the E36 ones had the best flow, sorry i have nothing  to back this up. 

[Riceburner]

Ok, if it’s going to be a horsepower killer it’s not a good idea then! Lol

[Aaron Neubauer]

I think mine is an E46.  Only match ported supports 201.6rwhp.

[gav240z]

If I recall correctly later ones are N36. I can't recall if earlier cars had a different casting code though (than E46).

I seem to recall discussions years ago that there was 10hp difference between 240z and 260z intakes. No idea what data this was based off of.

Edit checked manifold from my 70 Z and it's an E46 manifold.

[Aaron Neubauer]

Porting can fix any flow problem though  there is heaps of wall thickness in any SU manifold to work with to improve flow path particularly at cyl 1/2 and 5/6 divisions.