Weather and its effects???
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From: Sierra Vista, AZ
Weather and its effects??? Ok, a while back I had only headers and true duals, stock internals; I ran 12.8 @ 107. Then I swapped in a TR224 @114 cam using the LS1 intake, and began to run 12.5 @ 108-109 tuned at 12.9:1 afr, 31* timing. Now, I swapped in a TSP 231/237 @ 112 cam and an LS6 intake, I am now running 12.5 @ 108-109 same 12.9Afr, and 31* timing. The weather was warm and humid, but no idea what the DA was today or last times. I know weather can hurt you but this much? I figure the mph would be up more then none! Does a split cam hurt NA performance that much? I was also told I should be running a little bit fatter AFR for optimal power, when I thought 12.9 was prime?
No the cam is not freshly installed, its been in a month, and the intake a week.
For those with a similar cam where should the shift points be at? Mine are currently shifting at 6200rpms. I think my heads suck big mule.........
No the cam is not freshly installed, its been in a month, and the intake a week.
For those with a similar cam where should the shift points be at? Mine are currently shifting at 6200rpms. I think my heads suck big mule.........
damn, you didnt get any heads for er yet?, is this after the tranny rebuild, maybe they f'd up, dosent sound right, did you try changing timing? the weather could hurt you as much as .2 it's done that to me from one day to the next
TECH Resident
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From: Knoxville, TN
Weather can have a HUGE effect. If you would like to get an idea of what the DA was on each day, and how it might have affected your performance, list the following info and I'll look it up for you:
Track(s) you made each run at
Day of each run
Time of each run
Bob
Track(s) you made each run at
Day of each run
Time of each run
Bob
7 Second Club
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From: Gainesville, Florida # of drag strips runs: ?!?!?
my car in a year of bracket racing went from an 11.88 best in -750 DA in January to a 12.35 worst in June with a 3500+ DA, so yes the weather can affect your times! You need to watch those sort of things when you make changes to really know what your car is doing. Rule of thumb (READ:every car responds to weather differently) is every 1000 foot of DA is a tenth of a second.
Derek
Derek
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From: Sierra Vista, AZ
Bob, I will post or pm as soon as I find the old cams slip to at least compare it to the new one.
So ill feeling.
One of my friends said I might want to shift sooner, and I said hell no, this cam wants to shift late. My shift vs rpm is 6200 with a rev limiter at 6700. So, I went an did a manual shift one run, hit the rev limiter 1-2, and then went back into 1st, then 2nd again, and then rev limiter in 2-3 and finished...basically held it or beyond the 6700 limit, and made an honest 1mph gain. Maybe I need to raise it.
Thanks guys,
Charlie.
So ill feeling.
One of my friends said I might want to shift sooner, and I said hell no, this cam wants to shift late. My shift vs rpm is 6200 with a rev limiter at 6700. So, I went an did a manual shift one run, hit the rev limiter 1-2, and then went back into 1st, then 2nd again, and then rev limiter in 2-3 and finished...basically held it or beyond the 6700 limit, and made an honest 1mph gain. Maybe I need to raise it.
Thanks guys,
Charlie.
