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Hi All,

Finished rebuilt the engine for my 1970 Gto Ram Air 3 (M20 transmission and 800 CFM Q-jet carb). The engine has it's stock pistons back. Everything is stock except the camshaft, i put the Crower 60423 and the HEI distributor. I am adjusting the timing tomorrow and do not know the adjustments for the initial and total timing. I run 93 octane and do not have a problem with detonation.

Thoughts
 

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Hi All,

Finished rebuilt the engine for my 1970 Gto Ram Air 3 (M20 transmission and 800 CFM Q-jet carb). The engine has it's stock pistons back. Everything is stock except the camshaft, i put the Crower 60423 and the HEI distributor. I am adjusting the timing tomorrow and do not know the adjustments for the initial and total timing. I run 93 octane and do not have a problem with detonation.

Thoughts
Do a search through the past forum articles on timing adjustments. Use the "Google Custom Search" box in the upper right hand corner of this page. Much on timing and setting your distributor and advance curve has been covered. Should help you out and answer your question. :thumbsup:
 

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Nobody can give you exact accurate numbers for your particular engine.

One engine may idle better at 12°, another at 15°, another even higher.

One engine may need 36° total advance, another 34°, another may run better at 32°.

It's best to set for your best total advance 1st. It's the most important. Then, if when the best total is set, your initial is not where you want it, you'll have to change the amount of mechanical advance your dist makes. It's common for HEI dist to have too much mechanical advance. In that case you need to add some sort of positive advance stop, to limit the amount of mechanical advance the dist can achieve. There are several ways to do this.

Then you have the vac advance. Many stock vac advance units add too much advance. Adjustable vac advance units are available.

https://www.amazon.com/Crane-Cams-99600-1-Adjustable-Advance/dp/B000CIO2JU
 
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