How Far can the Lean Cruse be tuned??

Discuss General Motors (GMC, Chevy, Pontiac, Hummer, Cadillac, etc) tuning topics here. Request definitions, discuss parameters, etc.

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racprops
Posts: 1
Joined: Mon Feb 01, 2021 10:54 am

How Far can the Lean Cruse be tuned??

Post by racprops »

I am building a special low/medium RPM 383 for a Star Craft 93 Custom G20 Van: the goal is for a high MPG engine able to pull a van at 75/80MPH at 1500/1800RPMs and product 20MPG +.

After much research I will be running a 87 TPI intake and was going to buy a Dynamic EFI add on board BUT it will not work with my current 16168625 PCM, so I am told to run two PCMs piggy back.

Has anyone here run this system?? Is it really worth the cost?

The NEXT question is can I turn on the Lean Cruse or highway mode in a 625?? Or program it in? I have a custom chip set up that was supposed to be such. Because of miscommunication it was installed incorrectly for a decade and was NOT working…for all I know the van might have been running on its basic tables.. which could be why it only got 14MPG no matter what.

Once I have been able to fine tune my PCM for the Van engine and drive train I cannot see making any farther changes, it will be once tuned and done. I then plan on getting a couple PCMs with custom chips burned.

The major question is can I do as much with the stock PCM system and Tunerpro or do I really need to do the dual PCMs to reach a fine tune. I figure I do not need to spend $500.00 just for a one time super tune.

Also I have instructions on how to convert my 625 TBI PCM to handle the TPI’s eight injectors.

I also have a used Eprom Emulator to allow running the PCM on a Laptop for the tune. (Never tested hope it works...)

I do not have a eprom erasurer nor burner…will be looking for help there as well.

I figure to run a TPI Tune to start...

Wonder if there are any tuners located in Phoenix AZ I can work with?? ONCE this virus thing is over…

All help is welcome…this is a project that I started back in the late 90s…and life got in the way, no some 20+ years I am putting this together as last.

Thanks.

Rich
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