964rh

6100rpm


Rob

964 C2R

Thanks for sharing your valuable knowledge with us, Geoffrey. Do you have any figures of stock engines (at least internals) and/or with different exhausts (i.e. Stock, Cup bypass, G-pipe, cat-bypass, different headers and what not) configurations available?

>Rob, thanks for the rpms.


Cheers,


Daniel Saxlid

Geoffrey

I know I said I was going to do a dyno test with a number of chips that people had sent here, but due to all of the crap here on the board regarding "pushed timing" and such, I have pushed that to the bottom of my priority list (which keeps growing at the moment). I do have some exhaust information that I've posted before on the difference between the secondary muffler, open airbox, cup airbox, and some other pieces of information from a test done on a new blueprinted 964 Cup engine.

jneteler

I'm not really sure what the difference is between open and boxed skirt but I know what I would prefer on a date.

I did see some interesting pistons last year. The Milan Airport duty free shopping area has a Ferrari memorabilia store where they sell all the usual stuff. There is also a section where they sell pistons with connecting rods mounted on a wood base. You could buy all variety of pistons including Formula 1 types that were at least ten years old. What struck me was that the skirts were almost non-existent, just enough for 1 ring and some for the wrist pin, and that they were very small compared to pistions coming out of airplane engines. Of course, they didn't have to last very long either.

JNeteler

Geoffrey

Here is a picture of the differences between pistons. Piston on the left is a 9M boxed skirt piston in 103mm, piston on the right is a stock 100mm 964 piston. See the added structure supporting the wrist pin. The piston on the left is considerably lighter than the piston on the right.

sten gr

Hello Sweden
My 964 engine delivers 306 Hp
389.2Nm @ 4718 rpm. on dyno “a”
Almost 390 Nm was hard to believe, so tried another dyno,
393,2Nm @ 4770 rpm. on dyno “b”
The heads are resurfaced, so it got a slightly raised compression.
Standard headers, cat, secondary muffler and cup pipe.
A part from cup pipe and the compression ratio the engine is standard (blueprinted M64/03)

sten gr

By the way what dia. is the wrist pin in the 9M piston?

Geoffrey

It depends on which piston is purchased. Their drop in "sport" pistons are 23mm and the "race" pistons are 22mm. Obviously, you can build a custom pistons with any reasonable compression height and a variety of wrist pin diameters.

I've done some BMW race pistons at 20mm