Mopar HiPo ECU ***** disappointing dyno #s enclosed

[SoCal Rebell]

Mods on my Viper are listed below, I dynoed my car 7 weeks ago with only 915 miles on the Arrow rebuilt motor, my only mod since then was the Mopar ECU and an additional 1,300 miles of break in. I had an authorized Viper tech put the ECU on and gave it 400 miles of "learning" time he results are awful to say the least. On the same Dynojet 248C with the same SAE correction I went from:

421.1 to 406.2 RWHP -14.9 RWHP
473.1 to 452.4 torque -20.7 lb. ft.

The difference is pretty even throughout the curve and the air/fuel mixture drops dramaticlly at 3,500 rpm becomes to rich. I've noticed it runs hotter, idles a full 300 rpm below normal and stumbles at low rpm. It's coming off today. Any theories.

 

[BurnR8]

strange deal....just dynoed mine and got great results with the ECU attached....435 RWHP and 489 torque....mods are similar....I have 3" headers, 3" straight pipes, powereffects mufflers, K&N's, smooth tubes and 70mm Throttle bodies...the thing spanks now...the air temp was about 70 and I can't remember what the barometer was....sorry to hear you went the wrong way...

 

[GTS Dean]

Unfortunately, your results jive with nearly everyone else who has installed the MP ECU. From what I've heard, you're better off spending money on hard parts - at least until somebody out there REALLY figures out how to reflash the stock engine controller. I still find it tough to believe that the JTEC controller has proven to be so hard to tweak. Doesn't anybody do this on Mopar V8 controllers? The guts are the same except with the addition of injector and coil pack hardware for the extra two cylinders...