having converted my '88 sami to run on propane I now need to re-curve the timing advance on it and are looking for ideas on how to do it and some other info.
This might be a long one
The info I need is how much the vacuum and mechanical advance advance the timing (in separate numbers) and at what rpm the mechanical advance tops out at.
what I need to do to the timing is limit the overall advance but it needs to reach maximum advance sooner in the rpm range. (Ex. if its at 10 deg. at idle and 30 deg. all in by 3000rpm on gasoline it needs to be 14 deg. at idle and 28 deg. all in by 2800 rpm) and there are a few ways to do it.
the first way is to throw a lot of money at it and buy a CD type ignition system (msd, mallory, accel) as with some of them you can buy an add-on controller that will let you retard the timing at programed rpms and add advance at others but, only some of the more expensive systems can do this.
the second way is to install a Megajolt Jr. on it this will require some fabrication of some parts (a 36 tooth wheel with one tooth missing to put on the crank), the ignition system off a '90 to '99 ford escort 1.9L, and a laptop (that I don't currently own). This will make it a distributorless ignition and will cost less than a add-on CD type ignition plus I will have complete control (CONTROL BWA-HA-HA-HA
) of how the ignition acts. I will have to program the Megajolt it will not run anything out of the box.
The third and buy far the cheapest option is to modify the existing distributor to get what I want. To do this I will need to find some weaker springs to put on the mechanical advance maybe limit how far the counter weights swing out and also limit how far the vacuum advance moves the timing.
I would like to try to modify what I've got as I can see my self doing it for less than $20 and ether of the other options will cost well over $100. The hard part is finding some springs to replace the ones in the mechanical advance that are weaker but not to weak any ideas where a source of small springs are? plus any ways to limit the vacuum advance?
Sorry for the long post any help would be appreciated.