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The general word for Chevy small block timing is initial at around 10-16 degrees, and 36 in around 2500=2800 rpm.

Has there ever been any studys that recommend timing for low compression vs high compression? Say for 8.5 and 10.0 compression?

I would think the timing would be different because higher compression burns faster, and generally higher compression engines have a better quench advantage.
 

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Discussion Starter #3
Originally posted by stilcrazee ...<br>
Rudy, do you get the feeling you may never get any answers on this topic?<br>
:laughing: yes:cheers:
 

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AlwaysWave said:
The general word for Chevy small block timing is initial at around 10-16 degrees, and 36 in around 2500=2800 rpm.

Has there ever been any studys that recommend timing for low compression vs high compression? Say for 8.5 and 10.0 compression?

I would think the timing would be different because higher compression burns faster, and generally higher compression engines have a better quench advantage.
The SAE 2002 Transactions Journal of Engines, ISBN Number: 0-7680-1287-2 covers this extensively beginning on page 238.

Ray
 

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Here's the Readers Digest condensed version on compression vs. timing:

The higher the compression ratio, the more spark advance the engine can tolerate across the RPM range, assuming that you are running gas with an octane rating that makes full use of the compression ratio.
Timing, compression ratio, manifold temperature and fuel octane are all bound together and all three need to be considered when designing a high performance, and high efficiency engine. An 8.5:1 engine can't sqeeze high octane gas enough to make use of the stored energy available; therefore, more spark advance in a low Compression engine yields less benefit than in a high compression engine

Take a look in the SAE Engine Journals published annually. If I find a link I'll post it.

Also, Higher compression ratios don't necessarily mean faster burning. This is actually dictated by cylinder pressure, which is the product of compression ratio, valve timing, and engine health
 

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I have found that in WOT More is not always better..

I was running 34deg TOTAL timing in WOT btu when I lower the timing to 30deg TOTAL I made more power. my ET when from a 12.68 to 12.55 and MPH went from 110 to 111.69.

Granted in regular driving conditions my timing is up near 40deg TOTAL with no retard, but in the upper WOT I think more is not always better.
 

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Discussion Starter #7
this fascinates me.:cheers:
 
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