Okay first let me say that i am still new to adjusting the timing but i want to learn and enjoy spending a lot of time learning and trying. The car is a 72 camaro, 350, M22, mild cam, street avenger carb, preformer intake, MSD digital 6 plus box, MSD pro billet dist., Edelbrock preformer n2o wet kit w/ 75hp shot installed but not used yet.

I just finished installing the new dist. and set the intitial timing at 10* w/ the vac line disconnected and pluged, 20* of mechanical advance in by about 3500 so 30* total right now. The dig6 box has an auto timing retard feature for the n2o so i dont think i really need to worry about that, i've got it set to pull 3* out when the selinoid activates, also the dig6 box has a auto timing retard feature during starting so it will start with a little higher inital timing set. I used a vac. gauge to adjust the mixture for peak vac.

SOOOO... where do i go from here, i want to get as much preformance as possible from my current setup from tuning it properly, plus im still trying to learn as much as possible. i have heard that i can increase the initial timing until i hear a pinging then back off, is this the next step i should do, and if i do this when would i hear the pinging, would it be at idle right after i increase the timing or would i increase it a few degrees then drive it and then increase it again?? what else can i do to time/tune for max preformance. Thanks for all your help and im shure i will have lots of stupid questions as i go so please bear with me


Doug "BEEF' T

do you use a vacuum gauge to set youre timing it seems low i have a 383 with mec advance my initial timing is 18 degress i pull 2 degress out for ever 100 horse shot of nitrous

So what was the issue with no spark? I'm at 14° initial and 20 deg mech.

no i had used the vacuum gauge to just set the mixture, the 10* im shure is low, i just set it there as a starting point and will go from there, but my question is where do i go from here, do i just keep bumping it up a little untill i hear a ping at idle, or ping when driving? what should i be doing now.

and k5jmp it was a bad coil, i took it back and got a new one and it fire up like a champ on the first try

start the engine and set the idle speed to around 850 rpm with the idle-speed screw. If your engine has a big cam and must idle at a higher speed, that’s OK. Note the reading on the vacuum gauge. Next, turn one idle-mixture screw in ½-turn and note the change on the vacuum gauge. If the vacuum reading increases—say, from 14 inches to 14-½ inches—move around to the other side of the carburetor and turn that mixture screw in ½-turn as well. Again, note the vacuum gauge reading; if the gauge continues to climb, then adjust each idle-mixture screw in another ½-turn. On most carburetors, turning the mixture screw in (clockwise) leans the mixture, while counterclockwise (out) enriches the mixture.

start the engine and set the idle speed to around 850 rpm with the idle-speed screw. If your engine has a big cam and must idle at a higher speed, that’s OK. Note the reading on the vacuum gauge. Next, turn one idle-mixture screw in ½-turn and note the change on the vacuum gauge. If the vacuum reading increases—say, from 14 inches to 14-½ inches—move around to the other side of the carburetor and turn that mixture screw in ½-turn as well. Again, note the vacuum gauge reading; if the gauge continues to climb, then adjust each idle-mixture screw in another ½-turn. On most carburetors, turning the mixture screw in (clockwise) leans the mixture, while counterclockwise (out) enriches the mixture.


yup, thankyou, i did that, it seems to peak just above 15". I know i probably should increase the inital timing, but how do i figure out how much to increase it

What heads do you have and whats your compression ratio

Older GM heads with bowl shaped chambers likes alot of total timing 36 to 38*

Vortec heads and aftermarket heads with kindy or heart shapped chambers likes less total in the 32-34* range.

Set your rate of advance to come in about 500 rpm sooner at 3,000 rather than 3500.

Try 16* intitial and 36* total all in at 3,000 rpm

great thanks, its stock heads for now, ill try bumping it up about 6* and having it all in by 3000 and see what hapens. Basically my question is though what am i shooting for, how will i know when i have it set right or maybe better yet when i go to far, what am i shooting for, lets say i do bump it up another 6* and its running great, should i bump it up again and if so what am i looking for to see if i went too far, thanks for all you help guys

"BEEF"

You need to install one light silver and one light blue spring to get your advance full in by 3000 RPM. You need to install the silver bushing to get 25 degrees of crankshaft advance, which would put your total at 35 with 10 degrees base. I'd time it between 10 and 12 with drives at each setting to see what it likes.

You can then try two light silver springs which will pull all the timing in at 2500 RPM, a bit sooner.

Stock heads are going to like 35 to 38 degrees of total timing.

All the above information is in the instructions that came with your distributor.

if you've gone too far it may ping on part throttle load, like going up a hill slowly, especially if you have vac advance hooked up.

once you get a good baseline like you have now run the car with some hard full wide open pulls and see if you have any problems across youre rpm range