: 425 engine w/ 454 TBI program?

05-02-10, 11:31 AM
Hey all, nice forum you have here.
I am not going to lie to anyone here, I'm a dedicated Jeep fan. I own 13 Jeeps in various states of restoration. With that many, I am in the need for something that can haul these around from time to time.
A friend gave me the 425 and TH400 out of his '79 Fleetwood and I descided to drop it into a truck. I then took the TBI off an '87 Suburban and wired it all up.
WOW, what a monster!!!!:bouncy:
The problem I'm having is the programing of the ECM. Its a 7747 ECM and the 454 tune is only getting 8 MPG.
Has anyone else done this yet? I'm sure I'm not the first and was wondering if someone has created a tune for this already? I am using Tuner Pro R/T and having a hard time figuring out the programming for this.

Thanks in advance for any help....


05-02-10, 11:41 AM
Oh, and heres some pics...