64post

iTrader: (5)

I have a 383 LS1 in a 3000lb car going 126 mph trap speed but falls flat off the
Launch when spinning up to4500-5000rpm. 30 lb McLeod flywheel, LS3/7 blade maf using remote fbody style IAT . Car was tuned some but had to stop when clutch was slipping, that has been since remedied .. Could this be running too lean @4500-5000 and if so, can tuner add fuel/-+timing at this rpm range to fix this condition? I think the hp is there up top but serious flat spot elsewhere. The new slicks have really exposed this.

ScottyBG

Any way you can data log it with HP Tuners and post the log for people to review? That's about the only way we will be able to see if it is in the tune. It would be good if you could also post your tune for review. Do you have a wideband in the car? If it doesn't you should put that on your short list. It would seem that it is very possible it is the tune, if the car was not fully tuned.

64post

iTrader: (5)

I don't have HP tuners. I have been in contact with the person that originally tuned the car . It's tentatively set up for 3/8/17 for some more work. I do do not have a wide band either, I do know it was 12.5 afr in open loop. Right now I'm looking at everything fuel related to see if it's possible for a loss in volume or pressure on launch. Going to fuel gauge on the cowl to see what's happening.