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Discussion Starter · #1 ·
I haven't checked the timing on my car for a while so i decided to check last night. 15 degrees at idle and something around 48 at 3000rpms!!! Its a Summit brand HEI that is vacuum advance, trying to turn it clockwise got it down to 15 degrees untill it started to hit the firewall. Do you think its a tooth off because even if i had the room to keep turning it the distributor would most likely be almost sideways. Should i pull it and take it one tooth counter clockwise? I'm taking it to my grandfathers buddy who raced big time "back in the day" and he's been a mechanic all his life, so i'm going to see if he can get it perfect and the carb dialed in to match, but i was curious if i should mess with it before taking it too him.
 

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Moving a tooth is irrelevant.

Are you checking this with the vacuum advance hooked up?

if so, disconnect the vac advance and check again.

AL
 

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Discussion Starter · #3 ·
completely forgot to, does the vacuum port on the distributor need to be plugged or just unplug it and check?
 

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completely forgot to, does the vacuum port on the distributor need to be plugged or just unplug it and check?

If you can keep the engine running. You only need to check total
 

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The best way to disconnect and plug the vacuum line to set your timing is to remove the hose at the distributor and shove a golf tee or something round into the vacuum hose to seal the vacuum at the carb. It doesn't matter if the vacuum canister at the distributor is plugged.

If you rotate your distributor fully clockwise and can only get the initial timing down to 15 degrees BTDC, your distributor is off one tooth. It doesn't matter as Al mentioned other than you can't adjust your timing any lower than 15 degrees initial plus it looks dorky with your advance canister pointing way over at the firewall. The best thing to do is to remove the distributor cap and then the hold-down clamp on the intake manifold and carefully pull the distributor up and out of the hole and then rotate the gear one tooth by turning the rotor with your hand clockwise.

This will give you the adjustability to lower your initial timing lower than 15 degrees if you need to plus when you do get the timing set to where you want it, the vacuum advance canister won't be pointing towards one extremity of the range of travel.
 
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