MSD Distributor set-up?
The MSD Distributors come with a set of springs, bushings and instructions on how to set the mechanical advance window and curve. What they don't tell you is where to set those numbers for optimum performance, without the knowledge to set it correctly it's a guess at best. Probably 90% or better of the MSD Distributors that we check in our shop or at the track need adjusting and it shows immediatly on the time slip.
I love the Guy's that say "10-36* and all in at 2200RPM" for everyone, right....and which particular tree do you do your work under? If this was true then why aren't they available with that set-up already dialed into them?
Here's how we start:
We first look at the Cam duration at 50
208-218 we pencil in a 16* base
219 to 224...18*
225-230...20*
231-240...22*
241-250...24
251-260+...26
Once we have determined this number we then look at the Tranny(Gear or Auotmatic), gear ratio, intake, header size, weight of vehicle, tire diameter, convertor stall, compression ratio, head type and some other small details to determine whether we go up or down from the base initial timing.
The timing events and how far we take the total is determined from all these numbers also. The end result is a perfectly matched curve and mechanical advance window to give you optimum performance.
As long as we get the correct information the distributor will work flawlessly and give you optimum timing for your particular combination.
So you look at those initial numbers and compare those to your MSD instructions and you'll see that the most initial you can get from the MSD bushings is 18* intial and that gives you a total of 36*?? typical CHEVY Curve, not a Mopar. Mopars with a flat top piston should not run more than 34* total so now the most you can get is 16+18=34*, not much room there.
We hand build new bushings for the MSD distributors to achieve the correct timing events, I've talked to MSD a 100 times about this and they are very reluctant to build any bigger bushings due to a liability issue. The typical Chevy Guy will put in the biggest possible bushing as Bigger is Always Better and detonate his motor to death on the 1st pass.
....which is fine as it keeps us in business.
Comes down to this:
"Nothing is a Bolt on, Ready to Run is pure BS"
I could spew information all day here, if you want to know more read my tch articles on ignition and Mopar Distributors in the tech section of our web site:
www.4secondsflat.comI've also just added a tech article to help you remove and re-install you distributor.
Don
