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I have a L79 67 Corvette with transistor ignition that I want to reset the timing to factory specs. I've heard that I need to mix some high octaine with today's premium fuel. Can anyone help me out on a good fuel mixture.
It's not likely that you will need to use anything other than unleaded premium.
The initial timing should be set in the range of 4-10 degrees. The total centrifugal is 30 so in the 4-10 initial range, total WOT timing is 34-40. If it detonates at 10, drop it to whatever is required to quell any detonation.
If this car is a fairly new acquisition, you should check whether the spark advance map has been modified.
There are a number of variables in the detonation equation - ambient temperature, altitude, locally available fuel octane to name a few. Most Corvette engines that are still in OE spec, including the spark advance map, will operate on today's unleaded premiums with maybe just a slight reduction in initial timing.
The RON spec for most high compression vintage Corvette engines is 99-100 and 93 PON is equivalent to 97-98 RON, so it's not that far behind vintage leaded premiums.
It's not likely that you will need to use anything other than unleaded premium.
The initial timing should be set in the range of 4-10 degrees. The total centrifugal is 30 so in the 4-10 initial range, total WOT timing is 34-40. If it detonates at 10, drop it to whatever is required to quell any detonation.
If this car is a fairly new acquisition, you should check whether the spark advance map has been modified.
There are a number of variables in the detonation equation - ambient temperature, altitude, locally available fuel octane to name a few. Most Corvette engines that are still in OE spec, including the spark advance map, will operate on today's unleaded premiums with maybe just a slight reduction in initial timing.
The RON spec for most high compression vintage Corvette engines is 99-100 and 93 PON is equivalent to 97-98 RON, so it's not that far behind vintage leaded premiums.
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