Are there any boost limitations on the 12AT Jspec dizzy?

 

The 12AT dizzy only retards the timing by a maximum of 5*. So to run more boost you will need to retard the static timing. One option may be to remove the centrifugal advance weights so you can run more static timing and still have 5* retard under boost. Either that or run a locked dizzy.

 

Revhead, Are you sure?

I was under the impression that it was a total of 20 degrees. I actually bought one in great condition from Australia, but I never installed it. I always wanted to do a check with a vacuum pump/air compressor to see what the maximum advance and retard actually were.

In theory, it would have made my old blo-thru system MUCH more responsive than the locked distributor I had in there.

 

yea i think revhead is close. it was only good up to around 8psi or so. after that it was like a locked dizzy.

 

Thanks for the information. I have been running 10psi, and considering increasing to 12psi as there is a large FMIC. Will now rethink my plans.

 

you'll be fine, just back the total timing out a little. as long as you dont go over 10 degrees TOTAL advance you will be rockin out! mine is always locked... 10 degrees advanced at 16psi. works beautifully