timing help

[69PonyRider]

ok heres the deal, the way that my cleveland is performing right now isnt what id like it to be and i think its got something to do with the timing. I have and MSD 6AL w/ Blaster 2 and distributor. I recently purchased the car and the engine shook way too much so i checked the timing and it was at 30 deg, and 650rpm's i set it to 25 and later found that its supposed to be set at 6, is this correct? it is currently at 6deg and idling at about 900rpms, i think it should be idling at around 650 for auto right? but it backfires too much so i left it at 900 rpms. The shaking stopped but it feels sluggish, it needs a lot of gas to get going and sometimes backfires at the carb. Im not sure about this timing thing my dad helps me out with all this but hes no expert either, so what should the timing be set at or how do i go about figuring the right setting. Im guessing that 6 deg is for stock ignition systems, it ran pretty good when at 30deg once it got going but it shook way too much. could the sluggishness be also a carb thing? ill see what i get from you guys then ill ask more things. thanks in advance.

[73 Mustang Boy]

The backfiring probably does have something to do with the carb. I am going to run through how to adjust everything in one fatal swoop so hold on. First, unhook and plug the vacuum line going to the distributor. Then if you can use a vacuum gague to set the timing for the highest vacuum reading. If you dont have a gague just set the timing arround 12deg (thats usualy a good starting point). Then go down the page and look at the post titled "stalls when gassed" follow the instructions there on how to reset the idle mixture screws. Then reset your idle speed to get a good smooth idle (probably arround 700). This should take care of the problem, you may not feel as much power with the timing set lower but 25-30deg is way too much.

[Rev]

I think somethings wrong with your timing advance curve. Set your initial advance at about 10-13 degees. From what you're saying, I'll bet you aren't getting anything after that. You can tell that with a timing light. Either the vacuum advance or the mechanical advance is not working. You can tell which one by disconnecting and/or connecting the vacuum to the distributor and reving to 3000 or so. If your not getting the required extra advance either from vacuum or from centrifugal advance, then you will know where work is needed. At 3000, you should have 30-35 degrees of advance.

Rev