Last time at the track I was runnin consistant 13.6 w/ 1.9 60' at 100-101 mph. This time I was runnin consistant 13.6 again but I lowered my 60' to 1.7'. Amd my mph stayed at 97. WTF. The only changes I made to the car since last time was 109 octane. The elenation at the track is 3075ft and it was colder yesterday than the last time I went. Please give me your opinions...

 

you should run the lowest octane gas possible without detonating

 

Tire Pressure?

 

OK, so stick to 91? Tire pressure was 8psi up front an around 30-32 in the rear...

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 1SICJDM &raquo;</TD></TR><TR><TD CLASS="quote">OK, so stick to 91? Tire pressure was 8psi up front an around 30-32 in the rear...</TD></TR></TABLE>

Well im meaning in between the 2 different time runs, where you running any different tire pressure?

 

i would have to say, that it is because of your 60' times. the better 60' time, will lower your MPH. you'll see and increase in mph(as well as a drop in the e.t), with the same 60' time if you gain more whp!

 

Last time I was on 91, this time I was on 109. Last time I was runnin 10psi, this time 8psi

 

use 91 octane again with 8psi and see what happens, try to keep your variables to a minimum when going to the track if possible so that you can see what works and what doesnt

 

race gas doesnt help unless your tuned on it that hy you ran a worse time i think

 

Barometric pressure and lower tire pressure were most likely the culprit. Whenever you make changes for drag racing it is a wise idea to change 'one' thing instead of making 'multiple' changes and then trying to pinpiont the problem. Making one change at a time makes it easier to see what works and what does not.
What kind of ECU? OBD1 or OBD2? What kind of motor?

 

The reason I ask about tire pressure is that I had a recent experience that tire pressure was at 14psi on drag radials running consistent 108. Then dropped to 10psi, went to 106mph

 

P28 chipped,OBd 1 and its a H22. I will try going back to 10-11psi on the slicks and back to 91 octane..

 

thats exactly what i was thinking

 

could be the clutch.