Last Friday was my second trip the the dragstrip, and first since installing the Scanmaster last fall. I've had the car for a couple years, but am new to the tuning aspect of it. I was a little disappointed...but should I be (and how much)? My best run ended up being only a 13.8 @102 with a 2.25 60' when running about 20 lbs of boost. This run was after a few runs and then letting the car cool down. A few other runs were as high as 14.3 @ 97 when running only 15 psi. Now admittedly, I haven't quite gotten the launch down. Launching with any more than 5 pounds of boost, the rear brakes couldn't hold the tires. I am also running with street tires (255 rear on GNX replica wheels) and 93 octane pump gas.
Some more background info:
The previous owner had upgraded the turbo (not sure what it is, but it does still have the stock heat sheild), the larger wheels, auxilary fuel pump.
I first replaced the exahaust (dual 2.5" ATR with Pitt Bull mufflers I believe) and the plugs and wires. Since then I have added a THDP (with cat), 42.5 lb injectors (009's I think), street chip to match (don't know which one other than to match the injectors), Power Plate, oil breathers, MAF pipe and K&N cone filter. I still have the stock thermostat. Just last week the fuel filter and motor mounts were replaced.
The scanmaster readings at idle are:
AF = 05
L8 = 37
INT = 127
BL = 105 (rich I think)
cle = 196
ats= 112 (as I was staging)
rpm = 800
TPS = 0.40
IAC = 27
fuel pressure was about 43 (vacuum on) and about 63-65 at WOT @ 20 lbs of boost.
The lowest recorded O2 reading at WOT was 760 (I think).
I started off making runs at about 15 pounds of boost while watching for KR, and didn't see any on the runs until I moved up to about 20 psi. This occurred on my fastest run, but I dialed the boost back a little after that so that I was getting KR of zero. I hadn't tried adjusting the fuel pressure at the track, but when had previously tried turning it down, I did seem to be getting some KR, so for now I left it alone.
Other than my lack of skills at the drag strip, and the fact that I'm using street tires and pump gas, should I realistically be expecting more performance? Would a different chip potentially make a difference?
In addition to trying to learn what I can from the board, I've watched other people's signatures and have noticed a few that perform significantly better while still using street tires and pump gas. I also realize how important the correct tuning and combination of everything is, and I've read through the spring cleaning and performance recipes.
My main goal for the car is to be as quick as possible (obviously) but still be fully emissions legal (I'm near Chicago) and be reliable as a daily driver (even though its not a daily driver). I'm not as concerned about it's racing potential at this time, but more wondering if based on its performance at the track if there could be something wrong or if I could be missing something.
Over all, the car runs great. It does seem to idle slightly rough, even with the new motor mounts. I also have the slight hesitation at throttle tip in, but only from a stop or slow roll when I hit it too hard. Other than that, it seems to run great.
As a side note, later that night while on my way home, a late 90's Firebird Firehawk happened to pull up next to me at a stop light. Neither of us jumped when the light turned green, but from a roll about half way across the intersection we hit it. He was VERY slowly pulling on me, but we didn't go far. At the next stoplight he said he was impressed because he claims to usually beat up Grand Nationals pretty bad and was impressed that I stayed with him. He claims his is a high 11 second car. The only reason I mention this, is because we both had a rolling start which wouldn't provide for the best performance for either car. And if I was able to more or less keep up, then maybe much of it is just coming down to my launch at the track. Or maybe his car wasn't really as fast as he claimed. Anyway...
Any thoughts, comments, or suggestions would be appreciated!
Thanks,
Ken
Some more background info:
The previous owner had upgraded the turbo (not sure what it is, but it does still have the stock heat sheild), the larger wheels, auxilary fuel pump.
I first replaced the exahaust (dual 2.5" ATR with Pitt Bull mufflers I believe) and the plugs and wires. Since then I have added a THDP (with cat), 42.5 lb injectors (009's I think), street chip to match (don't know which one other than to match the injectors), Power Plate, oil breathers, MAF pipe and K&N cone filter. I still have the stock thermostat. Just last week the fuel filter and motor mounts were replaced.
The scanmaster readings at idle are:
AF = 05
L8 = 37
INT = 127
BL = 105 (rich I think)
cle = 196
ats= 112 (as I was staging)
rpm = 800
TPS = 0.40
IAC = 27
fuel pressure was about 43 (vacuum on) and about 63-65 at WOT @ 20 lbs of boost.
The lowest recorded O2 reading at WOT was 760 (I think).
I started off making runs at about 15 pounds of boost while watching for KR, and didn't see any on the runs until I moved up to about 20 psi. This occurred on my fastest run, but I dialed the boost back a little after that so that I was getting KR of zero. I hadn't tried adjusting the fuel pressure at the track, but when had previously tried turning it down, I did seem to be getting some KR, so for now I left it alone.
Other than my lack of skills at the drag strip, and the fact that I'm using street tires and pump gas, should I realistically be expecting more performance? Would a different chip potentially make a difference?
In addition to trying to learn what I can from the board, I've watched other people's signatures and have noticed a few that perform significantly better while still using street tires and pump gas. I also realize how important the correct tuning and combination of everything is, and I've read through the spring cleaning and performance recipes.
My main goal for the car is to be as quick as possible (obviously) but still be fully emissions legal (I'm near Chicago) and be reliable as a daily driver (even though its not a daily driver). I'm not as concerned about it's racing potential at this time, but more wondering if based on its performance at the track if there could be something wrong or if I could be missing something.
Over all, the car runs great. It does seem to idle slightly rough, even with the new motor mounts. I also have the slight hesitation at throttle tip in, but only from a stop or slow roll when I hit it too hard. Other than that, it seems to run great.
As a side note, later that night while on my way home, a late 90's Firebird Firehawk happened to pull up next to me at a stop light. Neither of us jumped when the light turned green, but from a roll about half way across the intersection we hit it. He was VERY slowly pulling on me, but we didn't go far. At the next stoplight he said he was impressed because he claims to usually beat up Grand Nationals pretty bad and was impressed that I stayed with him. He claims his is a high 11 second car. The only reason I mention this, is because we both had a rolling start which wouldn't provide for the best performance for either car. And if I was able to more or less keep up, then maybe much of it is just coming down to my launch at the track. Or maybe his car wasn't really as fast as he claimed. Anyway...
Any thoughts, comments, or suggestions would be appreciated!
Thanks,
Ken
