MSD 12 or upgrade?

I just bought a good used MSD 12 for my Blown Alcohol motor.
I am debating on sending it back to get it upgraded to 20.

At what point is this a "must do".

I've always run the mallory MAgs b4 now.

this is on a

585 BBF
11.5.1 CR
Trick Flow heads
1471 Hi Helix retro blower
Enderle buzzard Catcher, K valve.

thanks for your advice.

 

Kind of depends on what Mallory Mag you had prior. How many amps was your Mallory?

 

you will get many different answers on this, but i say 12 is not enough, especially when you start making more boost. we run a 20 on our car and love it, i think it's enough for what we are trying to do with our deal. sure a 44 would probably run a little better, but they are also harder on wires,caps, etc. i would say go with at least a 20.......just my 2 cents
Darren Russell

 

I think it was about 5 amps

 

You could send it back and get it upgraded, and it would be serviced at the same time. Then you would know exactly what you've got and where you're at with it. But if your old mag was only 5 amps and you can afford to do some testing, run it as it is and see what happens. If the difference is not very noticeable, send it in. You might be quite happy with it as it is, you will be up and running sooner, and saved yourself a few bucks as well.

 

Our SM IV's are 4.1 to 4.3 amps. Zig does them.

I know of several succesfull pullers that run IV's and V's on Arias and Chrysler Hemi setups, HH 14's and seem to make it work just fine.

Somewhere I've seen a chart comparing MSD mags to Mallory.

 

We ran a single 12 with Veney heads and it ran just fine, (1471 TAFC ) we also had a 20 and it made no difference. We went to a 44 after 4 years of running the 12 and it did not run any better. But we could run less Mag lead with the 44 with the same result.
Mark

 

Is the less mag lead with the 44 a direct result of the rise time difference?

I'm hearing this kind of info from more people.

 

That would make sense, although we would only be talking milliseconds. I guess at 8000 RPM a few milliseconds could make all the difference. And we all know what less lead time means...