Bumping up my MEFI 3 rev limit?
 

I understand that this is an ECU re-program for my 1999 502 MPI. My rev limit is at about 5200. Who can increase this by 150 rpm and how much will it cost?
Thanks
Greg

Az Speed and Marine can do it.(In Chandler)
Larry's Engine can do it. (also in Az)
Dustin at Whipple can do it. (In California)
Alexi at BoostPower can do it. (In California)
Pro Dyno can do it. (In Phoenix)
Pfaff can do it. (In California)

There are a ton of shops that can do those now. In the greater Phx area I gave you two, one in Tucson, and Three one state away.

Oh, and it should range from the $400's on up.

I thought the 502 MPI's used an MEFI 1 or 2 ? The hp500efi's use an MEFI3.

The earlier models used a Mefi 1. In 1998 1/2, they switched to a Mefi 3. At the same time, they went from V- belts to serpentine.
Oh, I can also do it. If you haven't made any other changes to the engine, just raising the rev limit is not really going to do much. We usually only raise the limit when a cam or head swap was done or a supercharger was added.
Eddie

I have heard that cam, new heads and superchargers are a good idea for the 502! Maybe even a new crank.

Mark at Precision Marine can do it, He also offers a OSO discount.Tell him Strip sent ya $$:D

504 469 7463

And some new rods, pistons, valves, springs, rockers, oil pan, oil pump, etc. etc. etc.:D

Ben at www.mefitunig.com will give you a print out of your current program and bump the rev limiter for less than $100

Wow. All good info. Thanks.

My current prop has me bumping the rev limiter and I have read some horror stories about lean conditions when you run that way.
I like running near the top end of the rpm range. Once the AZ summer kicks in, I lose about 100-150 rpm when the temperature hits 110° or so. Until then, I wanted to move the rev limit up.......but wont spend $400 to do it.
$100 seems reasonable though.

Call Us With The Numbers On The Side Or Rear Of The Ecm And We Can Help You! 877-bpower-4-u

So Jim is out of business.....interesting.

AZ Speed did a reprogram on my MEFI3 when the Whipplecharger was installed. He inserted a custom aluminum adapter with an O2 bung between the riser and the exhaust manifold. I think he did a decent job on the program because EGTs and plugs look good and I don't get soot on my transom. Unless you can improve upon what he did, I would rather leave the spark and fuel curves alone. Although, since the first reprogram, I did change to heads with 2.30" intakes.

Now the million dollar question.....
Is there any torque left in my setup above 5000 rpm??? Maybe I shouldn't be running there in the first place.

Ben is the guy to go to!

old thread.


lake test fine tunes it:drink: