Thread: -22 to -33 degrees timing on crossfire
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Old Sep 3, 2008 | 07:40 PM
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splinter
Joined: Sep 2007
Posts: 217
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From: Los Angeles
Default Re: -22 to -33 degrees timing on crossfire
Originally Posted by BlueStorm
hey guys, I plugged in a scan tool today and noticed while the engine was running the timing advance was between -22 and -33 degrees timing durring mid rpm revs. I use premium fuel so whats the deal, isn't this alot even at idle it's -22 degree?...
Your numbers should rightly be interpreted as advanced, i.e., BTDC. During light load and idle conditions, it’s perfectly permissible to have high readings such as yours. They serve to sharpen throttle response, increase part-throttle torque, and reduce fuel consumption.

It’s the WOT data that is most important to some, as those are what the DME is signaling while you’re having a go against the bloke beside you. Granted, supercharged engines are altogether different, as their 9:1 compression ratio combined with ~15 PSI+ and 91 octane are indeed a fickle combination. Because you are local, perhaps we can catch up to compare relevant/pertinent data and respective performance.

Your actual ignition spark advance can be easily verified by simply reading when it occurs with a suitable timing light against the harmonic balancer:

M112-113timingmark.jpg
 
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