Holley EFI

[gmachinz]

Well....a friend of mine gave me a vintage Holley ProJection TBI system that was installed on a motorhome with a 454 many years back. I like old school electrical performance stuff like that and I have everything to install it on my 86 K10. I stock NOS GM style dual tank selector valves so I plan to pull the q-jet off the truck and give this thing a go.

The Holley system was originally bought and installed in 1991 and has been in storage off the truck since about 1996. It had no problems so I plan to see how it performs on my 350.

[chevyrestoguy]

I'm very interested in watching your progress on this one. I am planning to eventually upgrade to one of the newer FI set-ups (Edelbrock, FAST, MSD, etc.) in the next few years, and the only thing that has me concerned is the external pump and how I can make it all work with dual tanks. Or will you run a pump in each tank and just have it go "hot" when you move the selector switch to that tank?

[gmachinz]

I'll be running both tanks via an NOS (stock) fuel tank selector valve and one of my new harnesses-the kit comes with a Holley red inline electric pump (puts out 15 psi) and the TBI unit has a built-in regulator to maintain fuel pressure. The control box varies the ground voltage based on TPS, coolant temp and the HEI tach signal. Its very basic but was the bees knees back when it came out. Should be a simple swap. Its the marine kit so it supports up to 390 HP. Its Pre CD/driver so there are several knobs to dial in the controller so it won't be too tuff....I just hope its OK from sitting on a shelf for the last 20+ years.

[ole dollor]

gona hang around and check this out ......kool ....

[waco]

gmachinc
Is it the 2 or 4 injector setup? I have the 2 injector model on my '76 chevy 4x4 & I still have all of install instructions for it. Let me know if I can provide any information. I used the tank charcoal can line as a return thru the selector switch.
Andy

[waco]

I just did a search & found that everything is online.

Just for the info: I only used 1 pump & filter setup down stream of the selector valve with no problems.

I did pickup 3 to 4 mpg in town. Don't know about long hauls, don't get out of town much with it.

Andy

[gmachinz]

Its the 2 injector version I believe....I'll post a few pics....brb....

[gmachinz]

Here we go....

[gmachinz]

A few more...

[waco]

That is the same one I have. Did you get the closed loop kit with it? It saves a lot of tweeking of the controller. Everything is done for you. I did add a supply & return pressure gauges just to monitor things.
Good luck with your install.
Andy

[gmachinz]

No, that wasn't included-nor was it part of the $600+ kit initially. Its possible Holley released it afterwards. But, check out the ecm "tuning" notes done on the original 454 it was installed on...! As far as I can tell, the ecm used coolant temp input for closed loop conditions after engine was warmed up-the potentiometers were the way to manually dial in whatever motor this thing was installed on.

[gmachinz]

Here's the "tune" results.....on a 454 motorhome.

[waco]

Sorry. Wrong choice of words.
I opted to add an O2 sensor to the setup (a seperate purchase, $90.00 I think). I installed it about 4 years after the orginal install. Thats when I noticed even better fuel mileage & performance.
Andy

[gmachinz]

I did check after you mentioned it and there does seem to be a $140 or so kit that is designed for it using a closed loop O2 sensor. I may have to look into it!

[waco]

I went through all of my files & came up with this bit of info on the O2 sensor. My kit is '94 model & required p\n 534-27 (Holley pro-jection closed loop kit) to add the O2 sensor to the system. I believe yours will require the same. The only 1 that I could find is from Fast Track Auto Parts at just short of $200.00. There is a small control box (3x2x1.5) that is required along with the O2 sensor. I believe the $140.00 setup is for the newer setups.
Andy