Track time finally!
Well Ed I may be guilty of passing on drag lore. Another one is "every 100 lb decrease in car weight =.1xx gain at the big end".Again more drag lore so not sure how accurate but I can certainly see any weight reduction should = more top end with all other factors =. You certainly have more 1/4 mi time than I do. If
I keep a spreadsheet on the few hundred passes I have made in my car. I see the "majority" of +.1 60' gain does =.1xx at the top end. I see in some cases I picked up .2xx and more but generally it = slightly more than the 60' time gain . These are all passes same day and generally within 5-10 degrees of air temp.
Beyond the time slip info I note date, air temp, RPM launch, lane, tire pressure and general notes like headwind, etc. Headwind at Fontana can be brutal some times of the year
Obviously several factors play in any +/- gain or loss
I keep a spreadsheet on the few hundred passes I have made in my car. I see the "majority" of +.1 60' gain does =.1xx at the top end. I see in some cases I picked up .2xx and more but generally it = slightly more than the 60' time gain . These are all passes same day and generally within 5-10 degrees of air temp.
Beyond the time slip info I note date, air temp, RPM launch, lane, tire pressure and general notes like headwind, etc. Headwind at Fontana can be brutal some times of the year
Obviously several factors play in any +/- gain or loss
If the 60' variations come from wheel spin, there are never 1/8 or 1/4 mile ETs more different than the 60' differences. If it is due to converter or tire changes, those can easily effect it down track. Since I had my car back halved, with 13" X 31" tires, it never spins at all anymore anyway. Did occasionally when I was running 9" tires.