[Grady Clay]

Dom,

I generally support the philosophy of doing sensible modifications but retain the ability to return the car to exactly original.

While I’m all in favor of larger displacement and more modern technology (DME not CIS), I’m not in favor of the additional weight hung out back on a nice light early 911. If anything, I would choose to reduce engine (and trans) weight.

The issue with using a 901 (or 911) transmission is they have limited strength. I would not encourage using a 3.0 and larger. Will it work? Sure but there is great risk. If you have the later ’69 magnesium pressure cast 901/13, I would swap for an earlier 901 or the latest 911.

A 915 will fit in a LWB ’69-’71 with only a little massaging with P-1 (BFH). A 915 in a SWB needs the rear seat metal replaced.


Taking a late 2.4 engine (7R case) and building a 2.7 or 2.8 MFI, S-cam, twin plug has the most appeal to me. It is both lightweight and powerful. A 901/911 can handle the power and torque if you are careful.

You could take a 2.4T, convert to 2.7RS pistons and use your 2.0E MFI and cams. This would keep your MFI in service as MFI typically doesn’t like very long term storage. With a little work, the 8.5:1 RS pistons can be set at 9.1:1 CR – same as the 2.0E. You can convert the 2.4T MFI to 2.7RS configuration.

While heavier, the 3.0 and 3.2 have some serious advantages. Once rebuilt and the head stud issue dealt with they are almost ‘last forever’ engines. CIS isn’t in the same “fun” league with MFI.

I have a 2.8S MFI in my 914-6 and have had both a 2.8E and 2.8S MFI in my ’68. I can tell you first hand how much fun it is.

Best,
Grady