I would only add that when unplugging the vacuum advance, to plug the vacuum source while doing your checks so the engine will not rev higher from the vacuum leak and confuse you.  Joe-JDC

JDC

I have them. I was hoping to hear first hand experience. Thanks though.

Durham Missouri

Here is a link to instructions for the MSD 8383
http://documents.msdperformance.com/8383.pdf




Lawrenceville, GA

Bringing this back from the dead. I'm going to change the factory MSD advance cure to more suit my driving style. Right now it has the heavy silver springs and the blue 21° bushing. I'm running 18° initial for a total of 39° at 4000 rpm. The motor starts and runs good with no pinging but I'd like to have everything all in around 3000 rpm. What combination of springs and bushing would you guys recommend? I'm thinking of either a red or silver bushing with 1 light silver and 1 blue spring.

Durham Missouri

Thanks Ted. I did a quick search on Ebay and there is a ton of the Penske lights on there cheap. I'll pick one of them up and compare to what I have. I don't want to keep chasing my tail on this.

Durham Missouri

Before MSD started selling their own timing lights, their list of recommended timing lights to be used with their multi-spark ignition systems was quite short; that list did not include any of the popular “dial back” or adjustable advance timing lights.  After trouble shooting several race cars that were repeatedly having engine trouble or simply not running right, those problems ended up being related directly back to ‘dial back’ timing lights.  I’ve seen those ‘adjustable’ timing lights off as much as 6° when compared to standard fare timing lights.  For whatever reason, when those lights are inaccurate, they are off in the direction of adding additional advance instead of the other way around.  For many years I used the Penske timing lights but within the last few years, I am becoming more of a fan of those battery powered lights that simply have two ‘D’ cells.  These particular timing lights work even on magneto systems or those systems that do not have easy access to 12 volts under the hood.
 
This is food for thought but if you’re looking for accuracy in the timing, then the timing light must be accurate.  With many of the race engines being sensitive to ½° changes in ignition timing, then you can see where this is going.
 
As far as putting a new timing mark on the damper that does not read enough degrees, a little math will help you out there.  Take the diameter of the location where the mark goes (damper ring in the case of most Y’s), multiply by pie (3.1416), divide by 360, and then multiply by the number of degrees you desire.  A new mark would then be transcribed to the damper from the TDC mark based on that measurement.  For a 6” damper ring, 38° would be a mark 1.990” from the original TDC mark.

Lorena, Texas (South of Waco)

I wish I would have thought of that before I put the motor in Charlie. I ordered a set of tape from MSD that goes from 5.25 to 8" so it should cover my dampner. My timing also has a dial to adjust for different degrees. I'll have to pull my cap off to see what arm I have.

Durham Missouri

You can also paint the additional marks, using the spacing of the original marks as the template.  I did that using a sewing needle dipped in paint.  This will be a lot easier with the damper removed.



Lawrenceville, GA

Once you confirm TDC on your damper you can use a tape.. or most dampers have marks from TDC to about 30 degrees. If you know you have 20 degrees of mechanical advance in your distributor, then by setting the initial at 18 using the marks on your damper, you should be at 38.. I have a timing light that will read advance and I use that to double check the results. If you install a timing tape it needs to be for the diameter of your damper. Otherwise the degree marks will be off..

Thanks Royce and Ted. I take it you have timing tape on your balancers? Or does a stock balancer have a 38° mark on it?

Durham Missouri