T vs. E heads
 

Hello, I have some conficting info regarding this. Waynes book indicates the heads for 73T and E are the same wrt. ports and valves can anybody please validate this. This is for MFI cars.

Thanks, Joe

Joe,

All 2.2, 2.4, and 2.7 heads have the same size valves ... 46 mm intake, and 40 mm exhaust. The same head part number was used on all 2.2 and 2.4 'S' engines, AND the RS 2.7 engines!

All of the 2.2 and 2.4 'T' heads I have seen had 30 mm intake ports, though I have heard of instances of some 'T' heads having 32 mm ports. A spare new-in-the box 2.4 911T MFI head I have has 30 mm intake ports.

I believe all 2.4 'E' heads had 32 mm ports.

I have calipered a couple sets of US-delivery T heads and found the intake ports to be 29mm.

I just took apart a stock 2.4 “T” motor and it had 29.72 Intake & 33.02 Exhaust ports. I thought that was really strange. My 2.0 “T” heads measured out to 31.75 Intake and 33.02 Exhaust. Is there a big discrepancy in the casting of these heads?

nein14-6, that difference in size seems to indicate that a different core for the ports was used. Does anyone know for sure that Porsche used sand cores? I doubt there would be 2mm difference for that size of port using sand cores.

2.0 heads and 2.2 heads did not share the same molds ... as there were several changes to the combustion chamber and valve angles.

Early_S_man, Yes I realize that the heads are different. I was just showing my observation that the Exhaust ports are bigger on both motors and the intake port is larger on my 2.0l “T” heads then on my 2.4 “T” heads.

Well, hope to have my heads off this weekend. that'll tell me for sure. I am looking at buying an E set up ie. stacks and throttle bodiesfor my T, but not sure if it makes sense if the intake ports don't match.

Joe