EFI Conversion Experience (long)

I thought it was time to summarize the installation of a Powerjection III throttle-body EFI into my '68 (390 FE, 4 spd). This unit used to be the RetroTek, before being bought by Professional Products.

I'd originally ordered the EFI kit from Summit complete with the returnless Fuel-On-Demand (FOD) module, fuel pump, filter, and braided hose fuel line kit for delivery in the spring of last year. With various back orders it arrived very late and I put it aside until fall. Not too happy with Summit at that point as they could have done a better job of communicating the delay. I didn't want to lose a few weeks out of the summer if there were issues part way through the installation.

The "install easily in an afternoon" claim was a bit of a stretch; this is my to-do list as I remember it:

1) install new fuel tank. I'd put in a new sending unit the year before, and the amount of crud that came out with the old one indicated a lot of corrosion in the tank. So, shiny new tank and new sending unit (with a good screen on the pickup) should eliminate the need for an additional pre-filter on the fuel line. The old tank was well bonded to the surrounding sheet metal with goo, and didn't want to part company. And not all the bolt holes aligned on the new tank with the old holes.

2) remove old carb from my Performer RPM intake.

3) remove carb studs as the EFI has a spacer plate that requires longer studs. Buy new studs, install them.

4) drop EFI on, but don't tighten anything yet.

5) wiring: control power (Key ON & CRANK). Fused 12V always-on power. Coil wire to EFI. Fuel pump wiring run through interior and drop down from the trunk. Fuel pump control wires from FOD to EFI & fuel pressure sending unit. Wiring for O2 sensor and coolent temp. Hook up Fuel-On-Demand harnesses to EFI harnesses. Run data cables from the FOD and EFI units through the firewall and into the passenger compartment.

6) coolent temp sensor: remove the existing temp sender from the intake manifold and install the EFI's sensor into that bung. For the instrument panel temp gauge you now need a new location for the sensor... the FE has a bung on the water neck, but mine was hopelessly seized... order and install new waterneck, lengthen wiring for the coolent temp sending unit & install. Involves a drain & refill of the radiator, of course. Coolent temp gauge shows Cold until the thermostat opens for the first time...

7) Vacuum lines. Some changes required from the carb. Small vacuum line from distributor as before. PCV hose to EFI throttle body. No hookup left for the power brake vacuum, so ran that one to a bung that was on the intake manifold (had to run out and buy an NPT-to-hose-barb fitting for it).

8) Fuel pump: needs to be located near the fuel tank and below it to self-prime. I built a bracket to hang it off the tank hold down bolts on the left side of the tank, but that put it awfully close to the exhaust tailpipe. Decided at this to ditch the original-style exhaust with its tranverse muffler and get the Dynomax VT system instead with true duel mufflers. And that's another story (**). Move the fuel pump bracket around to the front of the fuel tank. Remove mechanical fuel pump from the engine block and install a cover plate.

9) Fuel hoses. Discover at this point that the hose kit I'd bought, supposedly 15' and enough to do the whole car, was only 12' long with a ragged end on one end. Somebody who put that kit together shorted me on the end of the roll (or grabbed 3' off the end and did a crappy job cutting the hose). Did they think the purchaser wouldn't notice? Argue with Summit for a week for them to make this right. Had to convince them that after spending $2K on an EFI kit I wasn't trying to rip them off by claiming the fuel hose was too short. Wait for an additional length of hose to ship.

Routing the hose up the same path as the original hard lines, 15' was only going to get it there if I went to the back of the fuel rail. That makes for a cleaner looking installation too. Unfortunately, for some reason the back of the fuel rail is capped with a -8 AN fitting, when the rest of the system is all plumbed with -6 AN. There was also the matter of where to install the 1/8" NPT fuel pressure sending unit. The documentation indicates a possible bung for this under the throttle body, but it is a very tight fit and would require an extension nipple. Instead I ordered more hardware (-6 AN cap for the front of the fuel rail, a -8 AN to -6 AN reducer for the back of the fuel rail, and a -6AN union with a 1/8" NPT bung for the fuel pressure sensor) and wait again.

10) finish sawzall'ing out the old exhaust and install the Dynomax, including drilling a 5/8" hole just past the reducer to fit the O2 sensor bung. Install the 02 sensor and run the wiring clear of any hot exhaust.

11) torque everything down and give one final inspection.

12) setting Fuel-On-Demand mode to "Returnless". They provide a magnet for this that is supposed to switch the FOD module between modes. Nope, didn't work. Hook up my laptop to the data cable, turn the key on, and the system boots up for the first time. Able to set the mode to Returnless by the laptop. Fuel system pulses a few times maintaining 45 PSI as pre-set, then shuts down as its supposed to (non-running engine). No fuel leaks. So far so good.

13) setting initial parameters on the EFI. Hook the laptop up to the EFI data cable (a separate one from the FOD module), Key ON to boot the EFI's computer and connect, load the initial settings for a big block, set the approximate torque, and save.

14) the first try: Key ON to prime (fuel pump is quite noticable), then Crank. The engine fires immediately, stumbles for a couple of seconds, then dies. Very repeatable.

15) HELP! The Professional Product's forum is quite good, there are some helpful people contributing there. Quickly determined that my control wire was not hot when the key was in Crank position. So the engine was firing on the priming shot, but then not getting fuel to run on. Much time crammed under the dash until I finally found a magic wire that was 12V for ON and CRANK but not ACC or OFF.

16) Next try: Engine fires and runs. Go for a short drive around the block, laptop beside me. A bit worried as it was showing A/F ratios around 12:1 but soon enough as the engine warmed up and Adaptive Learning began, the A/F settled in at 13.7. First time I really stood on the gas there was all kinds of popping and hesitation, but the Adaptive Learning seems to be dialing this in.

I still have some work to do. Currently the idle is at about 1200 rpm, and I need to lower this (a combination of physically changing the idle screws and then reprogramming the software I believe). I really don't want to get into active tuning this thing... plug & play was all I really wanted. But all the parameters are there to play with if you are so inclined. Cold weather behaviour is much much better than with the old carb with electric choke. Word on the forums is that the electric fuel pump and the fuel filter delivered with the kit are both short lived, so have to spend another couple hundred bucks and upgrade - the Bosch 44 pump is apparently the best suited to pulse modulation.

So that was my "easy afternoon installation" :)
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Now I'm waiting on the Keisler 5spd transmission that I ordered in November with a delivery date of February 29. Which moved to mid-April when I enquired in March. Now they say mid-May. What is it with back orders and delivery dates in this industry?

(**) DynomaxVT system. I decided to go with the stainless 2.5" VT after reading a couple good things on the forums about this system. I ordered it through Jegs, and the customer experience couldn't be better. It arrived quickly without hassle. But on installing the kit I noticed a couple of odd things. (1) it comes with 4 exhaust hangers, but only 2 U-bolt clamps. All the rest of the clamps are band clamps, which simply do not work with the exhaust hangers. This is how the kit is diagrammed too, so someone didn't think that out. (2) the tailpipe extensions were labelled with the correct part number according to the diagram, but arrived as 3" tubes instead of 2.5". I emailed both Dynomax and Jegs about this, and Jegs quickly sent 2 stainless U-bolt clamps and 2 replacement tailpipe extensions at their cost. No hassle. Unfortunately the same problem - they sent 3" pipes, but the part number is correct as per the drawing. So someone either got the drawing wrong at Dynomax, OR someone is putting the wrong part labels on their pipes. I'm giving up on this one and will find some lengths of 2.5" stainless exhaust pipe locally.
 
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Dont belived all the horror stories about the pump and filter Forums are the 1st place people will bash a product or company.Im not sure what "short lived" means, but i've had mine over 4 years and no issues.I've had Holley pump die quicker.

The manual tunning is not that hard.The idle is a bit tricky.Every time you adjust the butterflies, you have reset the TP sensor.