* Interesting 3.6 engine build coming up *

[Jeff Alton]

Bill, do you run 12:1 on pump gas?? Or is that the good old Mahle "12:1 but if you measure it they are more like 10.8" overstated ratio?

Jeff

[klaucke]

How do you get the wrist pins in if they are tapered?

[Craig 930 RS]

The ID is tapered - lighter

[don911]

Craig,
I assume you're not talking about the motor you just put in your car?

[Craig 930 RS]

No, this is a different animal -

[Bill Verburg]

do you run 12:1 on pump gas??

yes, 93. electronics cover a multitude of sins.

The ID is tapered - lighter

yes, thats why i posted the 2 pistons side by side, look at the normal wristpin on the 2.7 and compare to the tapered RSR pin, grams are critical on these components. Same w/ the valves 993RS are much lighter( and bigger) than 3.2 or 964 or any of the earlier valves.

[Chas White]

Why is this so asymmetrical? I would think an even balance would be most important with these things.
Thanks for any info anyone can provide.
C.W.

[Craig 930 RS]

Bill, do you also have the 3.8 heads/valves?

Have you run this on the dyno - FWIW, what were the #s?

THX

[Jeff Alton]

I am curious too Bill. I have a 3.6 comming in peices that I am going to put into my car. All options are still on the table including high compression 3.8 with cams. I searched but did not find much about your motor specs.

Thanks,

Jeff

[Bill Verburg]

Bill, do you also have the 3.8 heads/valves?

yes, sodium cooled 51.5mm and 43 mm

Bill Howard and I did our engines at the same time, he out bid me for some mg, RS intake manifolds, see his prevoius post w/ the link to Steve Timmins site, mine is #5 and Bill's is #6 under the 3.8 section

Why is this so asymmetrical?

Not sure what you are looking at, but the pins are axially symmetric.

[Chas White]

Originally posted by Bill Verburg


Not sure what you are looking at, but the pins are axially symmetric. [/B]

I mean the piston is different on one side of the pin from the other. There must be a reason for this, I'm just curious as to what it is.
Thanks,
C.W.

[Bill Verburg]

Those pistons are a slipper skirt design, advantages are;
Lightens the piston, which, in turn, increases the speed range of the engine. Reduces the contact area with the cylinder wall, which reduces friction. Allows the piston to be brought down closer to the crankshaft without interference with its counterweights.

[Craig 930 RS]

Also using slightly lager valves with smaller valve stems. Stay tuned.
Not my engine, btw.

[Bill Verburg]

All the 993 valves have ~7.9mm stems, compared to the ~8.9mm stems previously used.

base 993 was 49/42.5mm, going up tp 51.5/43.5mm. bigger are available aftermarket, a friend is using 54mm Ti in his GT.

talk about expensive

[speeder]

Seems like an awfully high money/performance ratio, I mean 300+ HP is not slow but certainly not high HP either. What am I missing here?

[Craig 930 RS]

All degrees of tolerance for the ultimate engine, Denis......ultimately none of this 911 ownership really does make sense, does it? ;-)

[CBRacerX]

Standing By...

[Craig 930 RS]

Does that say Motec?

[randywebb]

Whatever happened to the guy who was going to use m/c throttle bodies to make a cheap induction setup?

[Craig 930 RS]

Wasn't this guy -