What Effect would advancing ignition timing have on engine temp. ?
 

Re: 1972 450SL with 177.982 engine

What effect would advancing ignition timing from 5 deg. ATDC to TDC have on M117 engine temp. ?

Would advancing the ignition 5 degrees to TDC lower overall engine operating temp ? or increase it ??

Has anyone had any experience with running M117 engine at TDC vs 5 ATDC ? Opinions/ pros & cons ?????

thanks

Timing is 18 to 22 degrees BTDC w/o vacuum @ 3,000 rpm (factory). Check that it is at 5 degrees ATDC w/vacuum at idle.

Best results: set timing at 30 degrees BTDC at 3,000 w/o vacuum. Check: At idle the timing w/ vacuum should be about 5 to 7 degrees BTDC. YOu will get best running and fuel economy with these settings.

may run a tad hotter, but not much