advance curve

[76bonanza]

I have been tuning my msd pro billit HEI I have my intial timing at 16 and the 21 degree bushing for a total of 37. I have a mild 355 roller rockers mild cam and quick fuel carb desk top dyno 330hp. I have been fooling with the springs and am running the light blue and light silver and it runs like a bat out of hell.

It says when you hear detonation you have it coming in to fast or to much. I don't think I hear anything my exhaust is quite loud. my question is at 4000 rpm pulling hard will I be able to hear it ping? And will I hear it better with window up or down? With them up I don't think I hear anything with them down the exhaust makes alot of noise and think that is what I am hearing.

Thanks just don't want to ruin my motor but she is running real nice.

[72hotrod]

If your timing is too advanced, power will be lower. Seat of the pants evaluations can lead to misleading conclusions, but try to retard the distributor a couple degrees and see if it goes any better. If not, go back to starting point, if so, adjust your curve slower with more spring or tension,or run a little less total. It's pretty much trial and error, and I would rather be a little slow than broken. Another strike against too loud exhaust.

[airdale94]

Originally Posted by 76bonanza

I have been tuning my msd pro billit HEI I have my intial timing at 16 and the 21 degree bushing for a total of 37. I have a mild 355 roller rockers mild cam and quick fuel carb desk top dyno 330hp. I have been fooling with the springs and am running the light blue and light silver and it runs like a bat out of hell.

It says when you hear detonation you have it coming in to fast or to much. I don't think I hear anything my exhaust is quite loud. my question is at 4000 rpm pulling hard will I be able to hear it ping? And will I hear it better with window up or down? With them up I don't think I hear anything with them down the exhaust makes alot of noise and think that is what I am hearing.

Thanks just don't want to ruin my motor but she is running real nice.

I would think you could here it better with the windows up. Pulling hard, loaded, at 4000 RPM, if you have any ping you would hear it. Your power would also drop off, as it's pinging, and that you can feel.

[BCOWANWHEELS]

36 degrees max.......

[70c10]

Originally Posted by BCOWANWHEELS

36 degrees max.......

My truck is 42 degrees total and likes it

[76bonanza]

yes i agree with 70c10 there is never a set in stone number. from what I have read 36-38 is the sweet spot.(but every engine is diferent) And I am happy with 37. I dont hear anything wierd but you know how your mind plays tricks on you.