93z auto, stock with bolt ons. Street/ strip car but mainly strip. not a dd but runs perfectly on the street. My problem is when im racing the car down the track (runs 13.50's or so) at the 12 second mark of the run or 3/4 track as the rpms creep to 4000 in 3rd gear they just stay there, actually drops a little to say 3850 then climbs again to 4000 then finish line. Im runnin datamaster and i can see my knock count is at 500 on the line then 1700 when its starts to retard the timing at the 3/4 track mark. Any ideas i how to make it work properly. Could be a faulty knock sensor i guess. Could i leave the sensor pluged in but put a plug in the block to trick it? probably not a good idea. I have an adjustable fuel press reg, i thought about richining it a little as my plugs look a little snowy.....thx.

 

what have you done to the motor and running gear? has it been tuned? whats the fuel pressure doing while under a load and at those rpms?

 

freshened motor about 3000 miles ago. same internals just new rings n bearings. fresh tranny at same time. with s.kit n high stall. good mid headers,elec w.pump, cai, msd dizzy, coil, adj fpr. no tune. not sure of the fuel pressure at those rpms. really got to figure that out..

 

there is a posibility that the trany is not shifting correctly, there is a 3rd gear converter lockup on the 93 4l60/700r4 one of the only years to do it. you could try unplugging the five prong plug on the tranny and running it without the converter lock and see what that does. wont or at least should not hurt the trany, after reading up on it and found its not supposed to harm the tranny, ive done it with mine just seeing how it would handle it. a tune would give you the choise of when you want 3rd to lock. most 700r4s only lock in 4th. i like it, when it locks up its like having another gear so it sounds and feels like a five speed. i dont get to 4th in the 1/4. converter locks in 3rd at 90 and im a little over 110 for the 1/4 on a soft start. i dont think my rearend will handle a hard start with warmed up tires.

 

fuel pressure seemed to be a little off so i adjusted that to 45 at idle and unplugged that 5 prong at the tranny....went for a ride she ran perfectly at 3800-4500 rpm in 3rd gear. sweet. thx alot. not sure what fixed it though but i'll plug the 5 prong back in to see. also the fuel pressure is at 51 at wot, is that too high?

 

43 is normal yes 51 is too high. what injectors are you using? i would recomend a tune at solomon LT1 PCM Tuning - OBDI/OBDII PCM Tuning/Programming Service or pcmforless PCMforless.com
sounds like the tranny is having problems locking the converter, unplugging the tranny takes away the trannies ability to lock the torque converter.

 

sorry so long getting back craby. just stock injectors. ill look into the tune this winter..but i say that every winter.
i got a few more races in and ive noticed that my car is alot more consistent with the pressure at 51. consistentcy is good for drag racing. i leave it at 44 on the street. can u tell me what the repercussions of doing this will do to. so i have 51 sitting behind the stock injector..will that wear it out? should i put bigger ones in if i continue to do this. thx. also can u look at my other post today about what size resistor in place of my air temp sensor.

 

should not hurt the injectors. mpg will not be good but on the track thats of no concern. why not just use a temp sensor? there is a resistance chart for temp sensors at shbox number 19 4th Gen LT1 F-Body Tech Aids