Hot Rod Forum : Hotrodders Bulletin Board - View Single Post - Mechanical Advance Timing
View Single Post
  #8 (permalink)  
Old 08-31-2012, 11:59 AM
cobalt327's Avatar
cobalt327 cobalt327 is offline
Last wiki edit: Intake manifold
Last journal entry: 1980 Malibu Wagon
Last photo:
Join Date: Mar 2009
Posts: 5,031
Wiki Edits: 1616

Thanks: 128
Thanked 616 Times in 565 Posts
Originally Posted by ggevaert View Post
Ok, did lots of reading up and it's all figured out now.
1. ignored the advanced timing in the chain
2. Installed new MSD distributor as per proper distributor setup (i.e figure out TDC and point rotor to #1 cylinder)
3. Changed springs in distributor to ones that will give me full timing at around 3000
4. Removed and plugged vaccum advance
5. started engine and set BTDC at 12. (made sure idle was below 800)
6. rev'd to 3500 (timing was not increasing around 3000) and adjusted timing to 36.
7. back down to idle and noted idle timing is now 18.
8. took her out for a run and she had lots of power and no pinging.

Next steps is for me to figure out what the weights do to the setup that came in the advance timing kit from MSD p/n 8428 and whether I even need them. (springs are already in)
I then also need to figure out if I need to adjust the stock vacuum advance settings and whether I need to put in the vacuum advance stop or not. Any help is appreciated.

I have always used the stock weights and cam along w/the aftermarket springs. The stock weights and cam will give a smoother advance, and as long as the "all in by" rpm is correct and there is no mechanical advance at idle speed, there's no need to change them.

With the vacuum advance connected and the engine speed high enough that the mechanical advance is all in, the amount of timing you see should be in the area of 46-50 degrees. This usually requires using the stop plate to keep the vacuum advance from adding too much timing. The page cdminter59 linked to below has info on setting up the distributor w/an advance curve suitable for how the vehicle will be used- including the vacuum advance.
Reply With Quote