Strange fuel problem at the track last night...
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8 Second Club
Joined: May 2002
Posts: 1,043
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From: Toronto
Strange fuel problem at the track last night... I am hoping that someone might me able to shed some light on the problem I had last night at the track... I got to the track with too much fuel... around half a tank of 94 octane... I did a couple a couple of motor passes and the car ran champ aside from being a little slower due to the extra weight... I planned on spraying a 100HP shot later in the evening and was going to add some 110 octane but because I had so much 94 in the tank I decided to go with 5 gallons of 114 octance... all the fuels I run are unleaded. My car is 98 Firebird with a Walbro 340, with the 114 added the gauge read about 3/4 full... I never tried racing with this much fuel in the tank!
Here's where my problems started... I did about 5 passes and the car would sputter just after launching... the car leaves pretty hard in the 1.5x range... I noticed when it did this the fuel gauge would shoot up the full mark and stay there till I restarted the car... it seemed like after 5 passes the sputtering went away, I tried spraying a 100HP shot just before the track closed and it sputtered
In case anyone is wondering... here's what I ran, it's my new best on the motor...
10:49PM 800FT DA
60ft 1.531
1/8 7.0 @ 95.9
1/4 11.1 @ 121.2
Not the 10 second I was hoping for but a new PB on the motor... it's hard building a car to run well on the motor and the spray... my converter is a 3 disk type that is designed for nitrous and I am on a VERY tall tire to make sure I don't run out of gear when spraying... the car works much better with a 27" tall tire on the motor... I guess all these hurdles could be overcome with more motor
At this point I decide if I don't spray it on the next pass I will not get to spray it all I tried to bring up the bottle pressure, but the heater and alternator under drive pulley don't work well together and I had to make sure I did not kill the battery... I could not get the pressure much higher than 800lbs (not enough!). Here's my only spray pass of the night, another PB by a couple 1/100th's...
10:58PM
60ft 1.595
1/8 6.9 @ 103.3
1/4 10.70 @ 130.6
Here's where my problems started... I did about 5 passes and the car would sputter just after launching... the car leaves pretty hard in the 1.5x range... I noticed when it did this the fuel gauge would shoot up the full mark and stay there till I restarted the car... it seemed like after 5 passes the sputtering went away, I tried spraying a 100HP shot just before the track closed and it sputtered
In case anyone is wondering... here's what I ran, it's my new best on the motor...10:49PM 800FT DA
60ft 1.531
1/8 7.0 @ 95.9
1/4 11.1 @ 121.2
Not the 10 second I was hoping for but a new PB on the motor... it's hard building a car to run well on the motor and the spray... my converter is a 3 disk type that is designed for nitrous and I am on a VERY tall tire to make sure I don't run out of gear when spraying... the car works much better with a 27" tall tire on the motor... I guess all these hurdles could be overcome with more motor
At this point I decide if I don't spray it on the next pass I will not get to spray it all I tried to bring up the bottle pressure, but the heater and alternator under drive pulley don't work well together and I had to make sure I did not kill the battery... I could not get the pressure much higher than 800lbs (not enough!). Here's my only spray pass of the night, another PB by a couple 1/100th's...
10:58PM
60ft 1.595
1/8 6.9 @ 103.3
1/4 10.70 @ 130.6
