Can too much timing reduce HP?
Thread Starter
Le Mans Master
Joined: Oct 2001
Posts: 5,577
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From: Southern Maryland Maryland
Can too much timing reduce HP?
I guess the topic says it all, lets say you can run 31degrees and not have any knock could you end up with less HP than with say 28 degrees of timing?
Phillip
Phillip
Burning Brakes
Joined: Jun 2000
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From: Annapolis, MD USA
Re: Can too much timing reduce HP? (Phil97SVT)
lets say you can run 31degrees and not have any knock could you end up with less HP than with say 28 degrees of timing?
Safety Car
Joined: Mar 2002
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Cruise-In V Veteran
St. Jude Donor '09
Re: Can too much timing reduce HP? (Phil97SVT)
I guess the topic says it all, lets say you can run 31degrees and not have any knock could you end up with less HP than with say 28 degrees of timing?
Phillip
Phillip
Drifting
Joined: May 2002
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From: San Francisco CA
Re: Can too much timing reduce HP? (Phil97SVT)
In setting the advance for maximum power on the dyno, you increase the timing until the power falls off. As you pass the point of maximum power there is no audible knock while the power starts to drop off. This is only speculation but I believe knock is occurring as soon as the power starts to drop off, only you can’t hear it yet.
Melting Slicks
Joined: Feb 2001
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From: DFW TX
Senior Member
Cruise-In III Veteran
Cruise-In IV Veteran
Re: Can too much timing reduce HP? (Phil97SVT)
Yes. On pump gas I usually advance timing until it begins to knock. Depending on CR usually the most I run on stock cars is 28-29 degrees.
When I tune cars on race gas they usually don't knock so I advance timing until power goes down. I have run as much as 32-33 degrees of timing before!
When I tune cars on race gas they usually don't knock so I advance timing until power goes down. I have run as much as 32-33 degrees of timing before!
Tech Contributor
Joined: Mar 2003
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From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
Re: Can too much timing reduce HP? (Godspeed)
This was actually recently addressed in a Hot-Rod mag article in which they stated that the optimum timing wasn't the most they could advance without knock. The engine was a sb chevy/carb. They pulled back 2 degrees more than where there was no knock.
