To Much Timing on Low Compression Engine?

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JGC403

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As long as it doesn't start detonating, will low compression (8.5-8.9:1) take as much timing as you can give it? Is there a point that it won't make any more power even with more timing but it still isn't to the point of detonation?
 
There does get to a point where there are no power gains even if it isn't near the point of knocking. Additional timing after peak power has been reached only places additional strain on the bearings as combustion tries to happen too early. This makes the piston want to reverse direction instead of normal combustion. Of course it never will reverse, it just gets spark earlier than it needs. Sorta like putting the band aid on moment before cutting yourself...
 
As long as it doesn't start detonating, will low compression (8.5-8.9:1) take as much timing as you can give it? Is there a point that it won't make any more power even with more timing but it still isn't to the point of detonation?


It all depends on the load. If the vehicle is light, and you are cruising on a dead flat road with a tail wind you could probably run 65 total. A bit of load and out come the bones.

It's all load related.
 
I had a Chevy tool truck packed probably 12000 lbs 350 motor, this was back in the early 80's slapped a motor together out of a bunch of used parts the heads were later model with bigger chambers and it really killed the powers so I just kept turning up the timing, it liked 50 degrees so that were it stayed. Ran great up and down hills in the Ohio valley for 250000 miles and still ran great when I sold it.
 
There does get to a point where there are no power gains even if it isn't near the point of knocking. Additional timing after peak power has been reached only places additional strain on the bearings as combustion tries to happen too early. This makes the piston want to reverse direction instead of normal combustion. Of course it never will reverse, it just gets spark earlier than it needs. Sorta like putting the band aid on moment before cutting yourself...

If you were able to get to that point it should definitely show up on with your 1/4 mile times?
 
I know you asked about power; but don't forget there is just so much you can do with the stock dizzy, before you have problems at the other end. For instance it's rare to find a dizzy with more than about 25* in it. so to run 50* of power-timing would require an initial of 25*. This may work at idle or very lightly loaded. But the rate of advance might be close to 1 Degree per 100 rpm. So with an 1800 stall TC, the timing might already be 35*by then. I've never had an engine that liked that, and 25* may upset the starter. 'Course I've never had an engine that liked more than 36* power-timing.
So I'm kindof curious what you're thinking is.
 
You have to modify the distributor so the mechanical goes further, that way your initial is lower.
 
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