Hey all,
I left the the dyno this weekend scratching my head. I am not really worried about the numbers I got. Just strange to me looking at the logs I made while on the dyno, why the numbers really weren't any different between the 4 total pulls I made. Maybe someone here with a lot more experinece tuning while on a dyno could shed some light.
All 4 pulls netted within 1HP and 5Tq. Highest being 446rwhp / 451rwtq . Runs made on a Superflow Dyno STP corrected. 90* ambient.
1st 2 pulls done almost immediately after arriving from a 50 mile trip. 1st pull 2nd gear to 6200rpm. Torque converter unlocked. 2nd pull, second gear to 6200 rpm, torque converter locked. Expected to see a difference with locked or unlocked converter? Engine was warm. Blower hot. Logs showed I pulled WOT timing about 5*. Most of run at about 17* total spark advance due to IAT's in the 150* range and timing being pulled by PCM.
2nd 2 pulls done several hours later after truck had cooled off. 1st pull in 2nd to 6200rpm. TC unlocked. 2nd pull done in 3rd gear to 5800 rpm, TC unlocked. Most of run second set of pulls at 22* spark advance due to truck being cooler and IAT's not pulling timing. IAT's around 125* at the end of the pulls.
AFR on all 2nd gear pulls accoring to my wideband and sniffer 11.5 to 11.8. The 3rd gear pull AFR went rich to about 11.0 - 11.2. I have methanol injection on the truck and have yet to get 3rd gear AFR in line with it.
Anyway I think I would see differences in numbers for a +5* timing. Converter locked or unlocked? Hell 25* difference in IAT's should be worth something? What gives?