Macrobb, can you outline the procedure to do what you're talking about? What has to be removed, which way to spin the gear, how much. etc.
Alright, I'll try my best:
1. Remove the inspection cover at the front of the IP gear housing. This will let you see the 3 bolts and stud that hold the IP to the gear.
2. Clean this area really well, getting all the grease off of it.
3. Rotate the engine to a known point - I'd use the timing mark on the crank to rotate it to TDC. It doesn't matter the position, just that you can get back to it of needed.
4. Using a sharpie, mark a line on the housing and face of the IP gear, so you have a reference mark. When we rotate the gear, it will move but the housing marks won't, so you'll be able to see how far you went.
5. Remove all 4 bolts holding the IP gear housing to the block
6. Using a small prybar, lever up on the IP gear housing to break the seal. We need to get it up just enough for the IP gear to clear the cam gear. No more than about 1/2".
7. While holding the gear cover up, try to rotate the IP gear by hand, just a little. You only want it to skip one tooth.
When looking at the front of the engine, the IP gear goes clockwise to advance it(top of IP gear towards driver's side, which is opposite how you would rotate the IP).
8. When you think you've got it(and it might take several tries to get it only one tooth over - you are trying to feel the gears as you have them just out of mesh), tighten down the 4 bolts on the IP gear housing again and fire it up.
If it feels like you went too far, rotate the engine back to the known point(where all your marks line up again) and try adjusting it again. It's not that hard, and you have the reference marks to keep you close. One tooth is going to be perhaps the width of a normal sharpie line at the edge of the cam gear that you see through the insepection cover - you don't have to go far.
If you got it right, it should be a bit clattery when running. It should be noticably too advanced.
You will then loosen the IP bolts and "retard" the IP by rotating it back towards the driver's side a but until you get something that sounds reasonable. Tighten it back up, reinstall the inspection cover, and test it out.
You will then want to play with the timing a bit - try it a bit retarded from where you have it, and a bit advanced. See what 'feels' better.
If you see white/gray smoke on heavy acceleration(vs black), you are too retarded. If it clatters a huge amount, you are too advanced.
You'll also want to make sure to do your timing/power tests once the engine has warmed up and the cold advance has turned off - that advances it another few degrees.
In my opinion, doing this will get you a very reasonable timing job. No, it might not be book-perfect, but it will run well, and get decent fuel mileage and power.
(Typically, where you make the most power in an IDI is also where you get the best fuel economy, because the engine is "fighting itself" less, using less fuel to make the same output)
