Brian C

Just wondering if anyone has had their ECM's re-programed for the 500efi's & if so did you get any speed increases? Thanks.

Linster

Not sure if you can get any speed boost, but probally will get better mileage. Call Mark @ Precision Marine and he can answer that.

amarket1

Definitely call Mark @ Precision Marine phone # is 504-469-7463

dreamer

mine are thereeek now will report on the results next w

jdnca1

Bumped my rev limiters to 5900, and was able to pull 56-5700 on a set of 30 pitch props that were all over the rev limiters before. I had tried a set of 32 pitch that were slightly faster, but could not pull them very well. At the end of the day the boat picked up about 5mph from bumping the limiters. Not bad for 300.00 a motor.

Bryan Rose

I had Mark @ Precision Marine do my ECm and it cleaned up the soot on the transom but not sure if I picked up any speed....too many changes at one time....Happy to not have as bad of soot problem , still there but not as bad....Good guy to do it.
Bryan

Donzilla

I have 2 from precision marine already turned up 900.00 a piece. You do know these have been discontinued by gm food for thought. will seperate.
JIM

Brian C

Thanks for the info., I'll give Mark a shout & talk to him.

dreamer

mine got accidentally sent to arizona speed and marine, where i was gonna go at first till i did my research and decided to go with mark... well now that arizona has em and saw marks paperwork in the box... they said they allready reprogrammed em(with out any contact info OR payment info AND after i called to tell them the mistake!!) and are now asking me for payment to get em back....

need some OSO power!!

Joe

PMarine did mine on my last boat (500 EFI's). I would recommend making their other suggested changes when you bump the rev. limiters. Owens Racing did my engine work and PMarine did the computers. Gained between 2-3MPH. I would recommend PMarine to anyone for this work.

Remember - You, most likely, will need to reprop.

FYI - The guy who bought my boat called appx. 1 yr. after the sale, bragging about how well the motors run.