Hi, I assembled MS3 from DIYautotune, tested with JimStim 1.5. All tested good except boost/PSI gauge, with Mityvac pump reading 15" vacuum, Tuner Studio gauge shows 7.8" vacuum. I since installed in car, started 2nd try with surging idle. Adjusted IAC settings, some idle improvement. MS3's MPX4250 MAP settings are 10 at 0v, 260 at 5v. Changed 260 to 350, car idles good. Base MAP/engine off reading with MPX4250 settings 84.3 kpa(with 350 at 5v, kpa goes up to 113 with engine off), 84.3 kpa accurate for 5,000' elevation = 12.23 psi. Able to drive car, used TS VE Live's Autotune, was correcting cels till 30% throttl, starts missing. Any ideas to correct Tuner Studios MAP gauge? I've used 3 different vacuum gauge to compare to TS gauge. I don't think it 'd be wise to continue Autotune with incorrect MAP info. Thank You.
77 Pontiac 400 stock 190HP test engine,
HEI7 controlled w/MS3X,
bank 2 bank port w/38's,
LS1 75mm TB,
GM 4 wire stepper IAC,
Last edited by oldskool
on Thu May 17, 2012 8:43 pm, edited 1 time in total.