mechanical advance limiters/spring selection/confusion.

[melloelky]

http://www.pertronix.com/docs/instruction-sheets/D7100700.pdf
i didn't have any problem setting up my msd pro billet before and this similar but it's not working for me on paper.they provide a chart for the springs and limit straps instead of msd's stop bushing. I'm looking for all my advance in @ or around 3000.so I'm thinking 12 degree limiter straps and and the 12 degree copper springs.can anyone shed any light on this for me?

 

[64nailhead]

Need more info. What is your initial timing set at? What is your 'all in' timing set at?

Perhaps some motor specs as well i.e. Engine, compression, displacement, cam specs, etc.

 

[melloelky]

thanks 64.well,none if it's been set yet as i haven't used it,i can't set up my dial back light and see where it all comes in at @this time,i pulled out my current dist.i ran 12 initial before but never established total.it was in my previous 355 this ones a 406.10-1 compression.240/246 duration=508/510.110 lobe sep.i don't know what this motor is going to like but i'm trying to get a good starting point.

 

[64nailhead]

A dial back light, or timing tape on the balancer are necessities.

For a starting point I'd pick the silver springs and the blue advance limiter strap. Set the base to 16 and test from there. This should yield 32 degrees all in around 3000 rpm's. From there you should be able to add advance to find you're all in number.

Your motor looks like it ought to like 16-20 base base and around 35-37 all in by 2800-3200. The all in though needs to be found via testing during WOT pulls or on a dyno. Many factors will dictate these numbers, but it sounds like some of the factors are unknown, so the testing must ensue.

Not to sound to elementary, you are aware that you should do all of these steps listed above when recurving the distributor with the vacuum advance can unhooked?

 

[melloelky]

thanks 64.yep the balancer is degreed/a tape too and i have the dial back light.you're rite there's a lot of unknown,i was only able to drive this new combo for a few days before it snowed🙁 so there's much shaking down come spring time,yes it's returning.what a coincidence the all in range is the same as my converter range too. no worries about the elementary sounding I'm aware of the vac advance needing to be unhooked/plugged.

 

[64nailhead]

Hopefully you get the maximum out of it. Alot of guys get the timing and tune so that it's functional and leave the last bit on the table. Keep in mind that each additional degree of all in with worth approx 10-15hp.

Good luck and stick to it.

 

[melloelky]

thanks for the help,i'm looking forward to do digging into it.stay warm