Help with cam timing 930 w/C2 cams!

[germanspec]

I am needing some help with camtiming, using C2 camgrind in a 1979 930 Turbo 3.3. Does anybody know the specs for the settings? I have heard several, and want to double check. I use a dial indicator thats in US not metric, so, if you know of the settings, please let me know. I need to know the normal setting, and the max advanced setting.

Thanks

[aigel]

Those specs are in Wayne's book. I think 1.26mm for the normal setting. Maybe someone with the book handy can give you the rest. I take it you are asking for what is generally called the 964 grind, eh?

Do yourself a favor and get a metric dial gauge. There is more than one serious catastrophy that resulted from unit conversion.

George

[camgrinder]

The factory setting of 1.26mm for the 964 C2 cams are retarded in the engine. I recommend 1.2 to 1.4 mm. 1.4 is close to straight up in the engine. (1.4mm = .055")

[5axis]

convert mm to inches.
mm/25.4

example 1mm / 25.4 =.0393700blah blah"

1.4/25.4=0.0551"

1.2/25.4=0.04724"

david 89 turbo cab

[Porschephd]

Normally we set them to 1.4. This is pretty good setting for the 964 profile.

[aigel]

Wy do you retard them?

George

[camgrinder]

1.26mm is slightly retarded from straight up. This works well in a naturally aspirated engine.
In a turbo application the 964 cams should be advanced.

Advancing the camshaft increases the intake valve lift at overlap. (higher number)

[germanspec]

That makes sense, when I used these cams, they first came out with this grind for the 930, and nobody seemed to know much other than the factory setting of 1.26, so, we all set them there, and it has taken awhile to figure out why I have so much lag, its worse than the stock cams, but I rarely drive it, so, I thought I would ask as I saw something somewhere about the higher timing, and I am sure that at .54 or .55, (1.4ish) it should clean up that mess of lag, whats the highest setting it can go, is .55 it? is that max advance on this cam?

Thanks