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  #16 (permalink)  
Old 04-15-2013, 08:12 PM
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Spinn

Thanks for the quick reply

Ok so at idle with my timing light set to 35 on the dial I put gun on balancer and the indicator is not even on a hatch mark but my guess would be it could've been around 15 which would be counter clockwise of 0 (it stops at 10). Then as I pick up throttle around 2000rpm the indicator is at zero and as I continue to increase throttle the indicator is increasing to approx 21-22
This is with keeping the timing gun at 35

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Old 04-15-2013, 08:19 PM
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Ok so with dial at 0 and raising throttle at 3000rpm I'm reading 41-42

Also I think I need a new timing gun as I just melted my clamp on the exhaust header
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Old 04-15-2013, 08:22 PM
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I think your over advanced, and found the problem.

You want around 14-18 intail totaled at 36 before 2500 rpm. Good place to start with. 10-12 in the vacuum pod at whatever vacuum.
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Old 04-15-2013, 08:34 PM
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Quote:
Originally Posted by spinn View Post
I think your over advanced, and found the problem.

You want around 14-18 intail totaled at 36 before 2500 rpm. Good place to start with. 10-12 in the vacuum pod at whatever vacuum.
Ok cool. sorry for all the lame questions. But is the initial timing when my gun is set to 0 and I check timing when engine is just at idle? And what is the vacuum pod?

Also when I increased throttle past 3000 it jumped past 50 on the indicator
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Old 04-15-2013, 08:41 PM
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Initial is before the curve starts. Happens at idle. It does not include the vacuum advance .

At idle you should be at least 14 degrees advanced BTDC. Happier yet around 18.

There is a link with the info in this thread.

A vacuum advance pod is the bell object you see off the factory distributor. It has a hose running to the base of the carb for a signal.

It functions to improve cruising and part throttle operations.

NOT TO 50!

50 is a little high.

Last edited by spinn; 04-15-2013 at 08:49 PM.
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Old 04-15-2013, 08:46 PM
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Ok thanks for the info. I will check out that link also and adjust the timing accordingly. .....as soon as I get a new timing light
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  #22 (permalink)  
Old 04-15-2013, 11:55 PM
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Originally Posted by Zz4bronco View Post
Cobalt327 thanks for the info on the carb. I will check that once I figure out if I have the timing set correctly. Btw carbs are like jet engines to me so I will do my best to keep up.
No problem my friend- ask as many questions as you want.

The vacuum advance needs to be disconnected and the line to the carb plugged when you're checking the timing. Get back to us w/the timing results once you do that.

We need to know what the timing is at idle (vacuum advance disconnected and plugged, remember). This is the initial advance.

Then we need to know what the total advance is (rev the engine slowly and continue to increase the rpm until the timing stops advancing. That's your total advance. Knowing at what rpm the total is at is needed, too.

We'll also work on getting the idle vacuum up where it needs to be.
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  #23 (permalink)  
Old 04-16-2013, 10:14 PM
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Ok thanks for the help guys. I think I have the info needed to figure out where to go next

Quote:
Originally Posted by cobalt327 View Post
No problem my friend- ask as many questions as you want.

The vacuum advance needs to be disconnected and the line to the carb plugged when you're checking the timing. Get back to us w/the timing results once you do that.

We need to know what the timing is at idle (vacuum advance disconnected and plugged, remember). This is the initial advance.

Then we need to know what the total advance is (rev the engine slowly and continue to increase the rpm until the timing stops advancing. That's your total advance. Knowing at what rpm the total is at is needed, too.

We'll also work on getting the idle vacuum up where it needs to be.

I got a new timing light that works awesome. Now I don't even need an assistant to watch my tach!
Anyways here it is. I plugged the vac to the distributor and checked my timing at idle (approx 700rpm) with gun set to 0 and I got 17-18
Then I checked timing at 3000rpm and the mark was at 42 so then I wanted to figure out when my timing stopped at a specific rpm. So my advance started to decrease at the 2400 rpm range. It held steady when at 2500 rpm.
So from what I've learned, my centrifugal advance is 25

What do you guys think
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Old 04-18-2013, 02:25 AM
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Do i need to get a vacuum pump
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Old 04-18-2013, 03:45 AM
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Originally Posted by Zz4bronco View Post
I got a new timing light that works awesome. Now I don't even need an assistant to watch my tach!
Can you tell us which timing light you bought please ?
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Old 04-18-2013, 10:43 AM
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Can you tell us which timing light you bought please ?
Craftsman digital
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