fitech efi

[Harpoon PV2]

Originally Posted by twobjshelbys

Exactly. My dad would re-jet the old Suburban when we went from Iowa to Colorado on vacation.

We did that trip way to many times when I was a kid! Never remember my Dad changing anything. The best was the 66 Impala two door, wish I had that! Cheers, Dennis

[eschaider]

Gary,

You ought to give some additional consideration to the EFI fueling approach over the carb. If you have your engine to the point it is reliable and doesn't leak too much, the EFI system will let you tune the start-up, idle, cruise, and WOT full power alternatives with extraordinary precision. The job is not impossible or difficult. It is more sophisticated than changing a jet or air bleed, assuming your carb tuning has evolved to that level.

The real beauty of tuning EFI is you use no tools it is all done from a keyboard, and can be done wirelessly. When you get to the road test, and data log, you will inch a step closer to your target with each iteration because you have extraordinary and repeatable precision available to you in the EFI fuel delivery model and then the data logging so you can see what hapened vs what you expected.

Some EFI suppliers give you an excellent base tune to start from, others have very nice learning capabilities to help. It seems daunting because it is new. The skills are not difficult to learn and the personal satisfaction reward is significant. BTW the car will start quickly all the time in all kinds of weather hot or cold, high altitude or below sea level

FWIW, based on what you have said so far about how you use your car, I would use a MAF based fueliing model.

[hinoonaz]

A lot to consider. Engine is solid. Spirited driving and on ramps. We do drive quite a bit tho not as much as iron but Karl. Maf seems right from what you have said Ed. I do not need max performance but can speed density be tuned to handle altitude variations without needing a lab coat??? Again, not racing just brag rights on who i can beat from a red light or giving rides.

[eschaider]

With or without a labcoat, altitude changes will require a retune on a speed density system. Significant atmospheric changes (altitude density) without a physical change in actual altitude, attributable for example to a weather front coming in or going out, will also require a retune. There is no way around the retune, it is inherent in the basiic design of the speed density fueling model. There is of course always the alternative where you simply ignore the need for a retune and it will respond similarly to a carbureted engine you choose not to retune.

[KarlzEE Bebout]

Get Miss Vikki to go out and change the jets for you....

[Steve Gallegos]

I started out with an Edelbrock PROFLO 2 direct injection in 2010. Switched to PROFLO 4 with direct injection in 2021. Could not be more happy. Set minor timing, it then sets itself to your type of driving.