[spuggy]

I had SC cams in my 3.3. Still do.

SC cams give more low/mid range and slightly less balls-out top end than 964, according to John Camgrinder Doherty (who ground them).

For most non-track purposes, the former is a lot more useful/usable than the latter. And you'll never notice the difference on WOT/full boost, except maybe on the dyno.

Based on something I think I read here, I originally got the cam timing set on the retarded end. Supposed to reduce the charge whizzing between the open valves under boost and make more power, or something. Dunno, it was a long time ago.

When I had the motor re-sealed (paper-thin cylinder base gasket got eaten when it "walked"), the wrench set the cam timing to regular SC specs.

He said "I think you'll enjoy that a lot more". He was right. Way more low and mid-range response, drove like an SC with a big-bore kit - and then the K27/HF would spool (6 PSI @ 2400, under enough load).

Best of both worlds, I think. I'd consider 964 or hairier cams if I was running EFI, but SC work great for CIS turbos.

The K27/HF stretched peak HP out another 6-700 RPM or so, but it's still all over, power wise, by the low 6,000's anyway - all you're doing is making a glorious noise by revving higher. Just because it'll rev freely to 7,000 RPM doesn't mean it's making more power by revving higher - you need the dyno charts to see that.

By the sound of it, you guys with bigger ports/better manifolds aren't seeing that much extra flow at the top...