ignition timing for 911sc - no vacuum advance.
 

I have a UK spec 911 sc which has no vacuum advance and it would seem that this is how it always was. All the info I have gives ignition timing settings with and without the vacuum attached but not for a car with none. Does anyone know what ignition timing settings I should use?

If you check your timing at 4000 or above, you should set the timing at about 30 degrees BTDC. All advance should be in so at idle the advance should be off at about 5 degrees BTDC.
It's important to know the distributor is lubed and working properly.
Bruce

I have a 930/03 Kremer engine, its distributor does not have vacuum advance, I did a bunch of reading about it...and to make a long story short, listen to Bruce.

I have the added advantage of a J&S Safeguard on my car that deals with knock, so I am a little aggressive with timing knowing the J&S will knock it back if needed.

Specs from Kremer for my 3.2 SS are:

Idle - 900-980rpm warm
Timing - 5 degrees BTDC at 900 rpm
CO 3.5-4.0%

Dennis

keysham,

The factory ignition timing spec for your engine is 25 BTDC @ 4000 rpm, with max timing of "not above 25 BTDC" @ 6000 rpm. The fuel spec was 98 RON.