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Discussion Starter #1
Replaced my stock distributor in my 67 GT S code (390) with a Mallory Unilite unit (non-vacuum). With the old distributor you always disconnected the vacuum line and then set the timing. I am assuming that with the non-vacuum Mallory unit, I just plug off the old vacuum port and set as normal (10 advanced at 650 RPM). Not a lot of information in the instructions that came with the new distributor, but seems to run OK. Have had the car since 67, and just had the motor rebuilt (Same block, heads, etc.) and it has 200 miles on it now. Just checking that I did this timing correctly. Too used to doing it with the old distributor I guess.

Thanks,

John:smile2:
 

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You need to verify how much mechanical advance is built into your distributor. You don't want the total advance (initial + mechanical) to exceed about 36*-40* or you may have pinging/detonation. You can verify how much mechanical advance you are getting if you put a timing tape on the harmonic balancer.
 

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Discussion Starter #3
I assume (there’s that word again) that you mean extend the existing advance markings past the 20 degrees that are there already. No problem doing that. As I mentioned, I have 10 degrees set in at 650 RPM, so if I rev the engine to say 3000 or 3500, I should not see more than 40 degrees advanced, correct?

Thanks,

John
 

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That's correct. You can buy a timing tape that's marked up to about 60* BTC and stick it onto the balancer.
 

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You can also buy an adjustable timing light that allows you to use tdc as a reference mark for total advance. No balancer tape marks needed. Pretty sure there are some fairly inexpensive ones available.
 

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Did you replace the stock cam with anything different ? If so, your actual results may vary as far as timing that is needed. It’s my experience that 390’s like timing ( just be careful not to go to the point of pinging,detonating).
 

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I ran a Unilite on my '69 Cougar many years ago. My Unilite had a vacuum advance, but likely that's the only difference. It came with a "degree key". I was a plastic key with stepped notches on it. You would insert it into the distributor for setting the curve. Can't remember much more, but FYI, you can change the ignition curve on a Unilite pretty easily.


Otherwise, it's the same as any other distributor. Keep advancing a few degrees at a time. When it starts to ping, back it off two degrees and you're there. (Some light pinging during a test drive won't destroy the engine.)
 

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You can also buy an adjustable timing light that allows you to use tdc as a reference mark for total advance. No balancer tape marks needed. Pretty sure there are some fairly inexpensive ones available.

It's called a "Dial-Back" Timing light and has a built in RPM gauge too. Takes little bit of learning's nuances,
Very Nice light.
 

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My 69 s code has a Mallory YL dual point converted to pertronics. Indygta is correct, my initial is 20 BTDC at idle with 16 degrees mech advance all in by 3000 rpm.
 
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