European Carrera RS pistons/ Cyl

[911schary]

Have a 77 911s. In Anderson's book it mentions the 3.0 upgrade using european carrera rs pistons and cylinders..
1.What year is he talking about, and where could I find these.
2.Do the spigots on my stock mag. 2.7 case need to be enlarged, and if so what are the durability issues involved.
3. Are different compression ratios available, and whats a good street compression running webers..

Any help appreciated..

zach

[jgparker]

Mahle does have 2.9 (93mm) P/C set available for a 2.7 upgrade, but they are a fortune right now. They do not require any machining to the spigots, but they do need a little camphor in the dome of the heads for clearance. They were $3150 last time I checked, but that was over a year ago. The only 3.0 upgrade that I know of looked like a hack-job, and you might want to avoid it. 9.5 or 9.8:1 is a reasonable starting point for single plug 94 octane Weber street engine. I'm preferential to a 2.8 upgrade myself...

[Wayne 962]

Not a good option for the 2.7 case - it's too weak...

-Wayne

[911schary]

Thanks... So we stay at 2.7

Zach

[Steve@Rennsport]

Hi:

The 93mm 2.9 sets are not a good choice for these engine cases and heads.

The cylinders are too thin for good ring sealing and head sealing. The case spigot openings remain the same as the 90mm or 92mm ones, but the cylinder wall thickness becomes an issue when hot.

I would consider the 2.8 92mm ones as the maximum practical size for these engines, regardless of case material.

If you were closer, I'd show you a little demonstration to help prove the point.

[red-beard]

EBS racing had 2.7 RS spec P&Cs for about $1700, or atleast they did last fall...

[Wayne 962]

2.7 is about as big as you can go with these magnesium cases, if you're not racing the engine, and not tearing it down every 24 hours...

-Wayne