P-mag timing

Got a quick question.
If I set my p-mag timing (jumpers are on) on 2 degrees past TDC would that help lowering engine temps? Or that would make it hotter?

I set min initially to 4 to 6 deg BTDC, initially. The closer you get to TDC the hotter the CHTs get. I think the idea is to fly at 4 to 6 and see what kind of CHT margin you get. Advance towards TDC incrementally, one mag at a time (so you can switch between then to check chts). With 1 Pmag I think you just leave at 4 to 6 deg BTDC.

Jumpers out (2 pmags) is a different beast, but the pmag guys will walk you through it.

Kurt

The short answer is yes, delayed timing (to a point) will lower CHTs.

The longer answer is why do you want to do this? Has it been a problem?

Back fitting pMags may result in higher CHTs, but that in not necessary a bad thing.

Carl

kklewin said:

I set min initially to 4 to 6 deg BTDC, initially.

Click to expand...

Easy to get confused with ignition clocking. Most EI's are installed and timed using TDC as the reference. "Clocking" (to reduce CHT, or add detonation margin, or ignite ATDC at cranking speed) means shifting the entire timing schedule by moving the initial set reference from TDC to something after TDC.

For timing retard, the new set reference is to the left of the TDC mark, as viewed from the pilot's seat. Picture here:

http://www.vansairforce.com/community/showpost.php?p=1383391&postcount=30

Thanks Dan