Mercer Motorsports

There is certainly a wealth of HPtuners and EFILive experience here. I was just wondering if there were any experienced tuners here that have used this package.

UMI racing PCM/Harness/Software. It's a Delphi MEFI4B PCM and the software is InGenius. Seems pretty straight forward SD tuning. Really just spark, fuel (IPW), and idle tables with some compensation tables for fuel and spark based on ECT, IAT, Baro, etc. But no VE table and only IPW X MAP X RPM tables to adjust base fuel. I think there may be some other tables that you can't see (low octane spark).. not sure.

I'm using it on a forged 402 with stock heads & intake, 10.8:1 CR, NA, mild cam (220 224 .551 110), UMI 90MM TB, 30lb SVOs, custom headers and a wideband AFR sensor.

I'm also running an Aeromotive fuel setup (Pump, Billet fuel rails, boost referenced regulator, etc)

It runs closed loop idle ok. Seem to be having a problem with it stumbling and leaning out when I get in the throttle. I plan to get it on the dyno soon, but want to get it so that I can drive it on the trailer first LOL. It comes with some canned calibration files and all of them seem to have the idle spark pretty low (9-15) from everything I've read this seems low anyway.

Any thoughts on idle timing? Set to idle around 900 RPM and closed loop idle is adding about 4-6 advance to timing (currently set at 15 for idle cells). I have an exported log file if anybody is interested in taking a look at it (.csv file so I can't post it).

Any feedback, advice, etc is appreciated.

ringram

Why didnt you run a stock pcm?
Yeah Id say idle you should be mid 20* range.

DrkPhx

iTrader: (15)

MY 402 sees about 25-27 degrees of total timing at idle.

Mercer Motorsports

Thanks for the info. The spark tables they provided are nowhere near that much advance at idle.

There are several reasons I didn't run a stock PCM. Main one was that I didn't have one. Also, because this is in a comp offroad vehicle. I needed something simple, durable and turn-key. UMI builds the motors for Robby Gordon's Baja trucks and has a pretty good reputation in the sport.

Also, I originally got a crate LS2 and needed a 58x setup (that motor only lived about 10 hours due to oil starvation). At the time, GM wasn't selling the PCM only and Speartech and UMI were the only ones I found that had the ability to handle 58x. Nothing against John. Speartech does some great work. I just decided to go with UMI.

It also came down to price and functionality, with this setup, I got the PCM, Harness, and the software to tune it for about what I would have paid for a PCM and custom harness alone.

Don't get me wrong, it's a great setup, it's just that they don't provide much documentation with it and not alot of folks seem to know about it and are using it.

I've been lurking and reading a lot on RedHardSupra's website and there's a ton of great info there. It's just more specific to EFIlive and HP Tuners.