Well no more rain. Finally got a chance to make some adjustments to fuel
pressure at the track. Results are:
Run 1 2 3 4 5 6
7
Pressure 42 42 46 52 38 38
44
R/T 0.57 0.69 0.852 0.671 0.573 0.435
0.569
60' 2.469 2.441 2.392 2.393 2.315 2.389
2.32
1/8 mi 10.058 10.052 9.969 10.01 9.888 9.91
9.838
ET 15.509 15.521 15.434 15.501 15.4 15.419
15.315
MPH 90.922 90.642 90.884 90.169 89.768 89.645 90.409
Traction was awful tonight. But at least it was consistently awful. The
first 2 runs seemed relatively close, so I bumped the pressure up to 46 lbs.
Didn't really seem to make much of a difference, as the gain in ET was due
mostly to the better 60'. Then I bumped it up to 52 lbs. Here there was a
slight decrease in MPH, and ET came up a bit (neither change was drastic, and
could be due to normal variations). Since I wasn't sure how high I could take
the pressure, and there wasn't much of a difference, I thought I'd drop the
pressure. This time I took it down to 38lbs. Now there was a noticeable
reduction in MPH. ET didn't suffer, but here again it was a better 60' time
that caused that. I ran again at 38 lbs just to validate the loss in MPH
(whoops I red lighted). Sure enough, MPH was down again. Then I jumped it
back closer to the starting point, to 44 and MPH came up, ET was down. I made
one more run (not shown) but missed 2nd gear (never missed 2nd before, 3rd
yes, 2nd no). It would have been the best run of the night too, as my 60'
time was 2.2.
I'm not sure what this all means. I thought that by raising the pressure,
there might be some compensation for the ported TB I'm running. But then
again, I'm at 3700 feet altitude. Maybe the altitude compensates for the TB,
and the stock fuel pressure of @42 lbs just happens to be right for this set
up????
This archive was generated by hypermail 2b29 : Fri Jun 20 2003 - 12:10:59 EDT