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Discussion Starter #1
I have a GMPP 290 HP/350, with a new HEI distributor and balancer (both are the part numbers recommended in the info that came with the engine). I have an Edelbrock Performer EPS manifold and 1406 carburetor.
I've checked the timing setup and I'm not sure I've got it set quite right.

Static timing - 12 degrees BTDC, with no vacuum advance, about 800 rpm
1000 rpm - 16 degrees BTDC
1250 rpm -21 degrees
1500 rpm - 26 degrees
1700 rpm - 28 degrees
1800 rpm - 29 degrees
2000+ rpm - 31 degrees

If I pull 10" or more vacuum on the vacuum advance, it adds about 17 degrees, for a total of 48 degrees of advance.

Most articles I've read have recommended about 36 degrees initial+centrifugal, and about 18 degrees from vacuum advance, for a max of 54 degrees.

Should I increase static timing? Or do I need to change weights to get more centrifugal advance?

Thanks,

Bruce
 

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Small block Chevy total advance should be 34 to 36 total, without the vacuum advance . If you adjust the total timing to 36 than add your 17 degrees you have 53 total , you should be ok. I don't worry about static timing just total. Joe
 

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Discussion Starter #3
Thanks for the suggestions. It looks like I'll try advancing the timing a little more and see what happens.

Bruce
 

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Discussion Starter #5
No, the 290 HP/350 engine has standard heads. Other than a more aggressive cam (222/222 at .050) its the same as the basic Goodwrench 350.

Thanks,

Bruce
 

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75gmck25 said:
Static timing - 12 degrees BTDC, with no vacuum advance, about 800 rpm
1000 rpm - 16 degrees BTDC
1250 rpm -21 degrees
1500 rpm - 26 degrees
1700 rpm - 28 degrees
1800 rpm - 29 degrees
2000+ rpm - 31 degrees
It's all in by 2000 rpm? I would be testing the mechanical curve to 4000 rpm just to see what's happening up there.
 

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Discussion Starter #8
I ran it up to 3000 rpm the same day and timing was the same as it was at 2000 rpm (31 degrees total). I'll try it again this weekend and see if it ever goes higher when I get up toward 4k rpm. I assumed the advance had maxed out at about 19 degrees centrifugal, since its a stock (but new) HEI.

Bruce
 
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