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Whats the maximum advance you can run before you start doing damage to an engine? I took my car for a ride last night and noticed it was pulling harder then normal on top end. Checked the timing and it was 50* advanced. Backed it down to 38* total and it seemed to not pull like it was before I moved it. Its a brand new MSD 6al box with billet distributor. I have the 20* bushing in it and run 18 initial and all in by 2500. I've heard some people say never go over 40. Is this true?
 

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Do you have the Vac advance hooked up when your checking total timing?

Timing is a reference. there is no magical Number!

a lot of factors!

You Can run more timing on low compression engine
More when using premium fuel or racing gas!

Some times a engine just wants more and works!

Some times it wants less!

Al
 

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There is no vacuum advance. Its a pro billet distributor with 6al box and blaster 2 coil. The motor is 12:1 and has a 50:50 mix of 93 octane and 110 cam2. Am I going to damage anything running at 50*?
I am not going to say anything!

Sounds like TDC is not true!

AL
 

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The amount of timing a motor will be happy at depends on the motor. I know of many motors that like around 38 or so, but have experienced first hand and heard of motors wanting in the 45 range. If the motor is pulling, it would appear to like that amount of timing, but you can always pull a spark plug and check for detonation to be sure. Just my two cents.
 

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Learn how to read your plugs. You'll be able to tell if the timing is correct by where the heat line is on the ground strap and center electrode.
http://www.dragstuff.com/techarticles/how-to-read-plugs.html

I totally agree with Big Al. 50* sounds like either the timing mark is off or the compression isn't all that high and it's running pig fat.:yes:
 

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Learn how to read your plugs. You'll be able to tell if the timing is correct by where the heat line is on the ground strap and center electrode.
http://www.dragstuff.com/techarticles/how-to-read-plugs.html

I totally agree with Big Al. 50* sounds like either the timing mark is off or the compression isn't all that high and it's running pig fat.:yes:
I agree, read the spark plugs. An old fuel trick is to lightly coat the threads with anti seize, make a pass. click the engine off and pull a plug. See how much of the anti-sieze is burned off the threads. Should be about 3 or 4. If it has burned more, you are lean, less u r fat. Another idea would be to install an egt. 1050-1100* is about right(mac temp on a pass). 1400* u r melting the pistons.
Also about the plugs, if u r too lean (too much timing) the electrode will burn some. and if u look at the plug real close (magniflying glass) u might see aluminum transferring from the pistons to the spark plugs. That's a great clue u r too lean. lol
one more item...if the camshaft is degreed in late (retarted).....the engine will take more timing. Ideally with your combo I would think 42* max. just fyi..I owned,tuned an alky injected dragster with Nos a few years ago. Best et 7.35. (always on a mild tune up-didn't want to pop anything, and was plenty quick)
 
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