Ignition timing for 72T.. should vacuum hose on distributor be on or off??

[IAN]

Anybody help me out?

Should the vacuum hose on the distributor be on or off on a 72 T 2.4 MFI 911??

Thanks!!!

[Bobboloo]

5 deg ATDC @900rpm + or - 50 with the vacuum attached.

[john walker's workshop]

that's a retard, so it can be unplugged. if you do that, then set the timing at full advance to the farthest notch to the right of Z1@ 5000 rpm (the timing SHOULD be fully advanced at 5K). if it pings, retard it a couple of degrees until it doesn't. the idle speed may have to be turned down if the retard is not used, but the idle will sound better with the timing advanced a bit.

[Early_S_Man]

Ian,

Check this thread for complete specs and discussion of distributor maintenance:

http://forums.pelicanparts.com/showthread.php?s=&threadid=5432&highlight=distributor+lube

[IAN]

I'm not quite sure which notch you mean on the fan pulley at 5k.

Thanks.

[Early_S_Man]

[Bobboloo]

What's the advantage to setting the timing at full advance? Is it because at full advance you can ascertain the most complete burn before the onset of detonation?