Volume III, Issue 8, Page 29
8/1/08

I have a 5.7 360HP Hemi Mopar factory crate engine with a Comp 268 cam and Mopar P4510342 ECU with 727 in my '78 Dodge Lil Red Truck. We get 310 RWHP but limit at 5700RPM. No one seems to be able to "tune" the ECU for say 6200RPM and maybe tune the Fuel/Air ratios. I've contacted most of the suppliers but to no avail. I don't want to purchase the $2300 adjustable ECU from Mopar. Any help?

Terry Swaney
Mead, WA

Terry,

Unfortunately there is no way to reprogram the rev limiter in the controller that comes with the 5.7 crate motors. MSD makes a controller that has 2 rev limiters that can be programmed but it does not use any O2 information and I believe that F.A.S.T. has one as well but I don't have any information on their unit.

Hope this helps,
Matt

If you’re stuck on a tough Mopar performance or restoration problem we have someone who may be able to help with fresh information and resources about classic Dodge and Plymouth parts. Matt Deane has been involved with Mopars all his life and is the Mopar Performance Parts specialist at SoCal’s Glendora Dodge. Now he’s offering his wealth of knowledge to Mopar Max readers and will track down the answers to your tough questions. Just fill out the form below and we’ll include his answers every month right here in Mopar Max. 

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