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Discussion Starter #1
Ok guys, I have a 383 with 10.4:1 and trickflow aluminim heads running on 110 octane fuel for right now. It has a Mallory comp 9000 unilite distributor that has no vacuum advance on it. I also have the Hyfire 6AL box. My cam is the Comp Cam 294 Extreme 250/256 @ .050 and .519/.525 lift. I also have a victor jr intake topped off with a 750 demon carb. It also has a 700r4 with a 3800 stall converter and 3:73's. My problem is I just got the car running this past weekend. I have a digital timing light and my buddy set the light at 20 degrees and then had me hold the RPM's at 2000 while he turned the distibutor so that the balancer was reading 20 ATDC when the light flashed. Now I thought it should be flashing when the pointer was at TDC, am I right? The reason I ask is because the car won't idle under 1200 RPM and it idles violenty! It looks like it's going tear the motor mounts out of the car at idle. But it starts right up cold or warm and the throttle response is very crisp! I have tried adjusting the mixture screws to smoothen up the idle with no help. Now I know that the car will have a radical idle with this size cam but I don't think it shouldn't shake so much. And yes the entire rotating ***. was externally balanced. Any help? Was the timing set wrong? Am I overlooking something? Thank you!
 

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... so the balancer was reading 20 degrees ATDC... yes, you are right, it should have been at zero

Do you have a degreed balancer with verified pointer? If you do, you don't need to use the dialback on the light, just set it to zero and read right off the balancer.

did you say 20 ATDC??? Should be BEFORE TDC! no wonder she won't idle!

With a 294 cam, start at a 1200 rpm idle, and work on the tune. Get a vacaum guage, and read up on how to adjust the timing curve on the unilite. It has a ford style advance, under the trigger plate, so it's kinda hard to get to.

you need to see what you have for a mechanical advance curve now. Check your timing at the lowest idle you can get, then bring the revs up untill the light shows it stops andvancing and take that reading. The difference is your mechanical advance.

You're gonna need to dial in as much initial as you can get (and still crank it over hot) to get any kinda of decent idle, then reduce the mechanical advance to limit total advance to 36.
 

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I think you need to find a new 'buddy'....
 

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Discussion Starter #4
Hey thanks for the info JimM. So to start you say start the car, leave the light set at zero then take the RPM up to say 3000 and adjust the distributor until the 0 "TDC" on the balancer is at 34-36 on the timing pointer? Thanks once again for everything. I'm going to go out and start to mess with it tomorrow afternoon. I'll let ya know how it comes out.
 
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