Alright, went to the track the other night, it was about 55 degrees out and clear sky, not sure about humidity. Anyway it was my first time running the car down the track. The 1st run was a 15.64 at 91.84MPH. I had a 2.5 60' and spun all threw first gear, short shifted into 2nd so try and get traction. I than sat in line for another half hour, it was PACKED, I left the car running because I thought they'd move quicker and I didn't want to keep starting and stopping my car. 2nd run I go against my dad, who know owns the IROC in my sig. We line up and I try going off idle, I bog down a little and had a 2.5 60' again. My dad beat me with a 15.0 to my 15.2 at 91.65 MPH. We sat in traffic for a long time again waiting to go but this time I had my car off most of the time. Anyway, I decided to take some advice from a coworker to start in second gear. I revved it to 2500RPM and it stall off the line. I ended up running 18.83 at 91.09MPH.

I know I need to work on my launchs, but my MPH is HORRIBLE. I bought the car back in march and I haven't done anything to it. I've changed all the fluids and thats it. I planned on doing the plugs and wires later on, but I'm thinking that maybe something is going on with them causing me to run bad. The thing is it didn't feel real strong at the track, but tonight when I was getting on it, it was hauling ***. Not sure what to think of it. I ran the scanner at work on it and all the sensors seem to be checking out ok. I need to check fuel pressure and what not.

Oh, When I checked my MAF the GM/s at idle were good, around 6-8 GMS, BUT when I was going WOT it was only going between 180-205. Granted it was hard juggling shift, watching the rpms and the scanner, but I think I did it right. Would that much of a difference in GM/s be the cause of my car running that slow?

 

An absolutely terrible 60 ft (like you have!) will affect mph. Not sure to what degree but a bad enough 60 ft will decrease your mph.

A stock LT1 F-Body will have 230 gps or so at WOT and redline (in 2nd/3rd gear). See if you can get somebody to watch it for you while you keep your eyes on the road to see if you just didn't see it go higher or if it is actually only going to around 200.

 

Do a search in the Drag Race section on launching with street tires. You should be able to get a least a 2.1 sec 60' on street tires. Don't launch from second gear. I'd suggest reving to about 2K rpm and let the clutch out quickly. If your car is tuned (plugs look good, wires, clean air filter) you should be running 14.0 in a stock car

 

Thanks guys, I will try to get someone to look at the scanner while i'm driving. I know I really need to launch better, I know thats one of my problems. I'm just hoping that maybe it was just a bad night, or that I can find something else wrong besides my driving. If the MAF was truely reading 200GM/S at WOT, would that cause my car to run that much slower? I replaced all the filters on my car when I serviced last so I'm sure they are fine. I also cleaned the throttle body. I'm thinking about using some of the GM top engine cleaner I have at work. I will have to look at the drag racing forum to find out how to launch well. About the launch your suggested, you mean rev to 2K and let the clutch out fast, not dumping, but fast THEN flooring it?

 

I ran a 14.9 @ 92mph w/ a 2.4 60ft time.........I have a really bad ignition problem though...(bad plugs and wires) hopefully I'll be a 14.1 when that's fixed

 

Dont feel bad, my LT1 cant break a 100. I took it out on a real cold night with street tires with the stall, couldnt get any sorta of decent sixty foor, all like yours, I was running high 14s at 98 all night long. When these Lt1s get hot they loose MPH too, I learned that the hard way. Bad sixty foots and heat will murder your MPH, bad sitys like a 2.5 will kill the ET.

 

Ya, I think I made a mistake by just leaving the car run while sitting in line. I'm going to have to practice launching my car and what not, but I also need to make sure everything is in running order. I"m going to retest the MAF and I'm going to change the plugs and wires. I'm hoping that along with a better launch maybe I'll get my car to run better and have it run where it should.

 

Well. I went back to work and hooked up the scanner again, had one of the guys there look at it and in 2nd gear towards the redline at WOT it was only reading 200 GM/S. Is there another test I can go to check to see if everything is working alright?

 

Try cleaning the elements in your MAF and see if that improves the reading any. Also try tapping it with something while the engine is running, and watching the readout on the scanner. I've heard of MAF's becoming sensitive to vibration when they start to go bad.

 

Thanks man, I'll try that tomorrow when I go back to work.