M104 Cylinder Head differences... - PeachParts Mercedes-Benz Forum

MAG58 · #1 01-21-2010, 03:18 AM

Quote:

Originally Posted by JayRash

My money is on the longer intake port, thou if ur planning to boost the engine the short port will work better since it wont reach sonic speed as quickly.

I mean to say on an NA the long port to the valves will help accelerate the intake charge helping both mid range and top end. the shorter wider port will flow at lower speeds, thou it might acctually work better at real high RPMs. this lower speed is a plus in boosted engines, but we r considering that you will be reaching either head's flow limits.

I'm not quite sure that's my point. The longer point will provide more uniform flow without the intake, but basically what I'm saying is the newer port seems to be something akin to taking about an inch or two off the origional intake and casting it into the head. I want to know how these heads perform with some runners bolted up, as that's how they're going to run. Flowbenching a head with now intake on it is mostly pointless, IMO as no gas burner I know can just run with open ports into the environment!

JayRash · #2 01-21-2010, 03:35 AM

Quote:

Originally Posted by MAG58

I'm not quite sure that's my point. The longer point will provide more uniform flow without the intake, but basically what I'm saying is the newer port seems to be something akin to taking about an inch or two off the origional intake and casting it into the head. I want to know how these heads perform with some runners bolted up, as that's how they're going to run. Flowbenching a head with now intake on it is mostly pointless, IMO as no gas burner I know can just run with open ports into the environment!

We cant really compare the length of intakes between CIS and EFI. if u look at the EFI one u will see its got even longer runners than that of the CIS, and by some margin too, and then there is the extra length in the head ports. I know for a fact those longer intake runners of the EFI manifold help in low down pull, but how would they perform for the top end? A compromise I say.