I bought the $450 msd distributor. It says it is fully adjustable up to +/-5. I have now idea how to do this and if it is a good idea to. Anyone else have one of these and played with it yet? The car is supercharged with a 6.5 psi unit if that matters. 94z with most bolt on upgrades and msd 6btm.

 

I think some others found that you only really use the timing adjustment if you have installed your cam advanced or retarted. You can use this instead of modifying the stock opti and just change your timing tables in the pcm. Some have noticed that they aren't set 2 turns out right out of the box like they should be, and the MSD techs have said you can achieve up to +/- 7* of timing. I would screw the adjustment screw all the way in, then count how many turn it takes to back it all the way out. Then I'd put it in the middle somewhere. Don't use this to adjust overall timing. You'd have to get a timing light to check what you're actually running which is a HUGE PITA on the LT1.