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Discussion Starter #1
I got a 302 / lunati voodoo cam 351 firing order / unilite distributor.


Set the timing light to 0 degree's, and set timing to 6.

As this is a high duration cam, wandering if 6 is correct ? I know 6 is for stock applications.


Any feedback would be appreciated ?

thanks
 

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I think mine is 12 at idle and about 34 when it's all in; around 3000 rpms. I would start there. I'm sure someone that know's more will chime in.
 

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Discussion Starter #3
I think mine is 12 at idle and about 34 when it's all in; around 3000 rpms. I would start there. I'm sure someone that know's more will chime in.



thanks, i set mine at 6 at idle .. had some old ford haynes repair manual, it stated to set it at 6. Then again, thats only for stock engines. I beleive the timing light should be at 0 degrees, im not definate on that either though.
 

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Do a trial and error. Step it up two degrees until you start to get a ping and then back it off. See how it performs at the various steps and then pick the one you like best. Timing at sea level would be less than those who are at higher altitude.
 

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Once you've made significant changes to the engine, you can ignore the factory recommendations - they no longer apply.

Most SBF's do best with about 10* of initial, and 34-36* total. The Unilite comes from the factory set to 24* mechanical. If you have a vacuum advance, you should set that fairly low, like 4-6*.

There's two ways to get the base timing set correctly. Put a glass of water on the fender. Turn the distributer until the ripples in the water are the smoothest. A more accurate way is to hook up a vacuum gauge to manifold vacuum. Where vacuum is highest is your best base timing.

Check the timing, and see where you're at. Then add or subtract mechanical timing to get you to 34* total. You might make more power with 35-36*, but it's a very small amount and your risk of detonation becomes much higher. To see if it makes more power you need to be on a dyno. Unless you're racing - with race fuel - stick with 34*.
 

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Discussion Starter #7
This is what happened to me, I was working on my project 66 stang, my 68 was working perfectly before. Took out distrubutor, to troubleshoot the 66, now just can't get my 68 to how it was before.

At first i had the timing way off, retarding it without a timing light, resulted alot of squeeling from my alternator belt and major knocking after 3000 rpm, even tach was jumping from 1000 - 3000 intervals, car was jerking. Took out plug 1- got my compression, the lunati voodoo uses the 351 firing order. Put distrubutor back in correct position, it might of been a tooth off.

Now after 3000 rpm - knocking is gone, but the rattling noise. Grabbed the timing light. I set the timing light so it reads 0 degrees. ( im not sure if it suppose to be 0, but thats what i set it to) As per factory default which is 6, i set the timing to 6. Knocking is now gone, rattling is just a tiny bit, very little after 3500 rpm.

I know im almost there now. I apprecaite your advise, but my question is the 0 degrees on the timing light ? Im not sure about that ?

Also what you mean by when you said 10 * of the initail ? Also what you mean when you say 34-36 of the total ? I got my timing marked 0-3-6-9-12 , so i set it for 6.

I know my unilite distrubutor for the 289/302 is not vacuum advance, its the mechanical one that uses the optical reading.
 

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I know im almost there now. I apprecaite your advise, but my question is the 0 degrees on the timing light ? Im not sure about that ?

Also what you mean by when you said 10 * of the initail ? Also what you mean when you say 34-36 of the total ? I got my timing marked 0-3-6-9-12 , so i set it for 6.

I know my unilite distrubutor for the 289/302 is not vacuum advance, its the mechanical one that uses the optical reading.
I think this is the problem right here. Those marks don't corrospond to ignition timing. If you look at this picture here, you'll see how the balancer is marked. You would expect to see it marked out in at least 10* increments.

http://i13.photobucket.com/albums/a256/bobcowan/TimingMakssmall.jpg?t=1243830562

I'm not sure what your marks corrospond to, but I'd bet 6 is way too much timing.

The first trick would be to find TDC (Top Dead Center). That means that the #1 piston is at the top of the bore on it's compression stroke. When you find it, mark the balancer there as 0*.

Make a mark on the balancer about 1" clockwise from 0*, that should be about 10* of advance. With your timing light set at 0, set your timing there. That should get you in the ballpark. Then you can use a vacuum gauge to set it exactly right.

It takes a certain amount of time for the flame front to go from the spark plug to the full bloom. At low rpm's, it doesn't take long, so the spark fires only about 10* before the piston is at it's optimim point. As rpm's increase, you have to fire the plug sooner and sooner to have it bloom at exactly the right spot.

The distributer has an advance mechanism. As the rpm's increase, the distributer moves that spark point earlier and earlier. At maximum advance, the spark should fire about 34-36* before the piston is at it's optimum point. Since you already have it at 10* at idle (static timing), you only need to add another 24-26* at speed (mechanical advance). 10* + 24* = 34*

If the spark fires too soon, the spark blooms before the piston is at TDC. Then it makes that ratteling noise you hear. That's called detonation, or pre-ignition. That's a bad thing. It's the sound of hundreds of little hammers pounding on your piston tops and lands. Things break, and you get this.

http://i13.photobucket.com/albums/a256/bobcowan/BrokenPiston1small.jpg
 

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Discussion Starter #9
I was thinking the same thing . . Mine might be to advanced. Your right. Im going to change that tommorow. Get Piston #1 mark it. My balancer has these markings 1-3-6-9-12 on there, it was marked like that when my engine was rebuilt by the machine shop, i beleive piston number one is marked correctly though. I'll do what you told me and im pretty sure as well that should get rid of the rattling noises.

I appreciate your help. Thanks man
 

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Remember that TDC can be on the exhaust stroke or the compression stroke - to set the distributor you need it to be on the compression stroke.
 
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