You are not paid to think , if the spark is retarded the EGT will be high , the CHT low.
That is a relative statement , as at this time you dont know where the tune actaully is.
The raw numbers ie max recall are pretty much irrelevant , its the rate of climb , of both cht and egt as you pull thru the rpm power range that is important.
CHT and EGT climbing in unison means all is good and safe , if you are using fine wire Platinum plugs then as you get close to optimum spark advance the distinct colour change on the earth electrode
will be at about 1/3 up from the weld.
Then as you lean down , the egt rate of climb will slow as you near peak power , and if you go one leaner with no increase in egt , and the cht is still climbing ,then its beginning to deto.
That is where you do a test to see if a little retard will bring the egt max up again.
The idea is to find the minimum advance that will generate max power with a certain fuel flow. Using fuel to cool an over advanced engine will make alot less power than a slightly retarded spark and a lean jet.
But that scenario means the bsfc is high ( Kgs fuel/Hp/Hr ) , and more power is to be found with optimum spark as well as the leanest jet , up to the limit where the egt starts to slow down its rate of climb nearing peak power.
Then of course you havnt even looked at compression.
All 3 of the main ingredients , advance , com , jet are equally important. But one is super simple to ballpark immediately - and that is , if the com and jet are close then the peak power advance will be 15* btdc.
If it makes best power on the leanest allowable jet at 18* advance , then the com is too low , and visa versa.
Ive got a thing thats unique and new.To prove it I'll have the last laugh on you.Cause instead of one head I got two.And you know two heads are better than one.
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