On big block 402 with 240/246 at .050 and a .574/.578 lift cam.....what would be an ideal area to set it at?

Set the total for 38*

Cool...what about the initial?

The initial will fal wher it may, but it should be aroung 16-18*.... If it's much higher, you may need to have your dist set up to change the curve...

So pretty much that's 20-22 degrees of mechanical curve?

Also how do you change the mechanical degrees? It's not with them liitle spring and weight kits you buy is it?

Also I've heard to do total timing you need a dial back light....I have one but I've heard (after buying one) that they are unreliable....would I be beter off buying one of those damper covers that has the markers on it? Could I still time it with a standard timing light if I went this route?

I have a Craftsmans dial back that works great. You can det the timing with a standard gun as well. Just look at the tap on the balancer.

...Also I've heard to do total timing you need a dial back light....I have one but I've heard (after buying one) that they are unreliable....would I be beter off buying one of those damper covers that has the markers on it? Could I still time it with a standard timing light if I went this route?The simpliest way is to buy a timing tape that adheres to the balancer. But, these have a tendency to come off so I would suggest that you use a small brush and some white paint to mark every 5° (or so) up to 40°. Then you can use a standard timing light (even after the tape "disappears").

18 intital/18-20 mechnical with your setup.

If you just go by total timing your inital can end up too retarded,for ex:

If your stock mech full adv is 30 deg (some stock gm dist are even more then this at times),then your only cranking in an additional 8 deg initial to get a 38 total when most perf cams like approx 18 deg initial .

This fact is often overlooked and running the inital timing 8-10 deg reatrded leaves alot of low end to mid power/grunt on the table esp with smaller cubically challenged motors like my 396 & 454's as compaired to the 496's/502s/572's many people are running these days.

But when you do run 18 deg initial with a stock type dist you almost always have to get the mech adv limited/recurved for 20 deg max to keep total at 38 deg otherwise the total can easily end up in the low to mid 40's which is too high for todays fuel & will detonate for sure unless maybe your running low comp (8:5)and a perf cam.

Dang this BS bout dial back's unreliability with MSD ignition. A few people perhaps had a problem but many more haven't including myself! My Craftsman dialback works perfectly with MSD 6AL and regular timing light confirms it! Nuff said!

or get a Digital 7, fix your advance and be done with it...

typically i'd set the timing between 34-38 degrees total, but not every combo is the same, not every timing light is the same, and not every balancer is going to be exactly the same as another. it's pretty much a trial and error if you want to get it perfect for YOUR combo. with that cam i'd want as much initial timing as i could get away with. i have the same cam in my 406 and i run it locked at 36* with a 20* start retard. works best for me.

Thanx for the input....FWIW I'm running a Mallory HEI. None of that high dollar unneeded MSD stuff is in my car.

I've always heard the way it works is total timing = initial + mechanical advance.

So now I need to figure out how to set the distributor up for a 20 degree advance....

Now something else I've always been curious about....when you guys (and gals) do the "36-38 degrees all in by 3k"....do you have a buddy rev and hold the engine at 3k until you have the line at ) with the dialback at 36-38? Or do you just set it for 18 initial and then set up the distributor for 20 mechanical advance?

Thanx for the input....FWIW I'm running a Mallory HEI. None of that high dollar unneeded MSD stuff is in my car.

I've always heard the way it works is total timing = initial + mechanical advance.

So now I need to figure out how to set the distributor up for a 20 degree advance....

Now something else I've always been curious about....when you guys (and gals) do the "36-38 degrees all in by 3k"....do you have a buddy rev and hold the engine at 3k until you have the line at ) with the dialback at 36-38? Or do you just set it for 18 initial and then set up the distributor for 20 mechanical advance?

I usually do it myself with a dialback light.. You can use your right hand to operate the throttle, while holding the timing light with your left hand & operating the dial with your mouth.. It is a little easier if you have help though :D

You could set your idle speed to 3k, they check to see if you have all your advance. Rev it some more and make sure there isn't any advance left.

You could set your idle speed to 3k, they check to see if you have all your advance. Rev it some more and make sure there isn't any advance left.

Yep, exactly. That way you know your springs are fully expanded for the mechanical advance. Go and get a balancer cover here, and never worry about it again. Just use 0 as your reference:
Balancer Cover (http://store.summitracing.com/egnsearch.asp?N=303651+215+115)

Does the balancer need to be removed for that balancer cover?

Does the balancer need to be removed for that balancer cover?

No, just your bottom pulley. I have one on the current balancer. Love it because I know exactly where my timing is at. I personally like the black ones, makes it easy on the eyes from the flash of the timing light.

Cool responses....

But how do I verify how many degrees my mechanical timing has?

Thanx again.

Cool responses....

But how do I verify how many degrees my mechanical timing has?

Thanx again.


Get your RPMS up 3000-3500 and use 0 as your reference on your timing tab, and check it against the balancer cover with your timing light. Make sure your vacuum advance is disconnected. Use the lightest springs on mechanical advance to see it come all in, and then set your timing to 34-38*.

If mechanical advance is kicking in too early and making your rpms drop too much from park to gear, then use a medium spring with a light one. Then your advance won't kick in until 1200-1500 rpms and you will have a steadier idle and less drop from park to gear. T

Are the springs what dictates how many degrees my mechanical timing is?

Thanks, I'll give that a shot.