FAST EFI Installation on 200 Inline 6

mark_hagen

New member
1967 Mustang Coupe
200ci/I6
Bored .030 over
Zero decked block
Standard Pistons
264/264-112 CS Cam
CI 2v log mod
Ported
V8 valves
HEI ignition
Headers
T5 transmission
8" rear w/ 3.25 gears

Purchased a Weber 38/38 DGES carb from Classic Inlines before Mike's passing. Found it near impossible to find anyone who; 1) Had working knowledge of tuning Weber carbs, 2) was willing to share their knowledge of Weber Carbs if the carb was not purchased through them. The car is a daily driver which will be operating at much higher altitudes soon, so we decided to bite the bullet and go with a F.A.S.T. EFI throttle body system.

Spoke to the FAST tech support folks and found that they do not share much information that isn't on their website. Asked if the Jeep 3.8L Inline 6 EFI system would work on a Ford 3.3L Inline 6. The only thing I was told was the Jeep I6 model has the same 4-barrel body but only two injectors. The reason I was given was that they could not accurately gain down all four injectors for the lower CFM engines. Other than that, no usable information given. I finally decided that cubic inches are cubic inches and CFM's are CFM's; so why shouldn't this work?

The Jeep specific model comes with an adapter plate to mate the throttle body to a Jeep bolt pattern intake manifold. The main problem with their adapter is that it will hit the valve cover unless it is raised up about 2 inches. Raising up 2 inches was not an option as hood clearance only allowed me another 3/4" above the Weber carb I had installed. Also, the 2v hole is orientated such that it is 90 degrees off the hogged out opening of the CI 2V Log Mod, if you want to use the OEM throttle linkage off the firewall. If you are using an aftermarket throttle cable, this may not be an issue for you.

I then set out to find a way to adapt the Holly style 4 barrel throttle body to my Classic Inlines 2v modded intake with Weber bolt pattern. I searched long and far for an adapter and was unable to find anything. So I decided to machine one myself. My first try was simply taking a 1 inch thick 4-barrel carb spacer and welding a 1/4" flat plate to the bottom, then drilling the Weber bolt pattern into the plate and hogging out the 2v opening. This did the job, but the airflow from the two passenger side venturies was having to make two sharp 90 degree turns before entering the intake manifold. I had a better option planned but just wanted to get the system running first, then we'd fine tune. For now, my rudimentary adapter plate seems to work Ok.

The system installed fairly easily. We had a muffler shop weld on a threaded insert onto the exhaust pipe for attaching the O2 sensor. The threaded insert came with a plug so you can mod the exhaust, then still drive the car while waiting to do the EFI install. We purchased a FAST inline fuel pump kit, which turned out to be a big mistake. More on this later. We installed the included FI rated 3/8" fuel hose from the tank to the throttle body. The inline fuel pump needs to be mounted below the level of the tank and, obviously, away from heat sources. The only place we could find was mounting to the inside of the driver side sub-frame connector. This eventually proved to be a bad plan. We used the 5/16 OEM fuel line as a return line from the fuel pressure regulator back to the tank. To get the fuel back into the tank, we ran AN-6 bulkhead fitting into the trunk and welded an AN-6 flared tube fitting to the filler neck. This became our fuel return line. When we started the car the first time, fuel started spewing out the back of the car so we shut down expecting the worst. What we realized was we left the fuel cap off and the return fuel was spraying out the open cap. If you decide to go this route (read on before you do), tap into the filler neck as far away from the cap as you can.

We mounted the pressure regulator to the forward side of the driver side strut tower. The regulator has a pressure gauge which needs to be visible during initial setup of the system. This also left the pressure regulator output line in close proximity to the OEM fuel line, for returning fuel to the tank.

We mounted the CPU on the firewall, just aft and towards passenger side of the valve cover. We mounted our throttle body with the linkage on the drivers side. We modified our OEM throttle arm on the firewall so it was about 3 inches higher and made a turn towards the drivers side. This allowed us to run a linkage forward to the top side of the throttle arm.

FAST says their systems are very susceptible to RF interference. The system also needs a valid, and RF-clean RPM signal. Call them for ideas if you are using OEM style ignition. You will probably need to get some type of tach signal generator for this. We are using an HEI ignition which has a tach terminal on the distributor housing, next to the BATT terminal. This IS NOT an RF-Clean source for the FAST tach input. You will need to get their tach module to filter or condition this signal. You can also purchase a FAST Distributor Module specifically for the HEI distributor, as we did. This module will replace the HEI distributor module and will have one extra output wire that plugs directly to the RPM plug on the FAST wiring harness. FAST claims better performance with their distributor module, over the HEI tach terminal and tach module, due to the cleaner RPM signal. My error in this respect was not asking if the FAST distributor module could take 18 volts, as we were putting into our HEI distributor. The short answer is, No. After running the car for 5 minutes, it slowly died and would not restart. While my son was cranking the engine, I noticed smoke coming off the distributor cap. What we found was the coil got so hot that molten dielectric had burned its way out of the coil. Another $150 distributor module later and another $25 coil later, sans 18v step-up transformer, we were back in business.

We finally got the car running and ran it through the initial setup and all seemed to go well. The engine ran much smoother and had noticeable higher power output. We had problems when rapidly pushing in the clutch and letting off the accelerator from 2000 rpm or higher. The idle rpm would drop way down close to 500 and the engine would either get close to stalling, or stalled altogether. We then ran into a bigger problem as the fuel tank got close to 1/3 full...The engine would miss or surge anytime we tried to accelerate and the fuel pump would start making a loud whining sound. After consulting with the FAST folks, we found that the inline fuel pump was located too far away from the tank, and as the fuel level dropped, the head pressure of the fuel in the line was not sufficient for the pump to suction feed. Our only option at this point was to purchase a replacement tank designed for fuel injection that had the fuel pump in the tank. Tanks, Inc, has a good tank with pump for around $450. So much for the FAST inline pump kit! The FAST inline fuel pump kit was $350, and I thought this was the way to go. This was an error on my part. I should have just ponied up the additional $100 and went with the Tanks, Inc. setup from the start.

Once we installed the new tank and pump, we had it running and back through the set-up menu. We still had some problems with stalls when quickly dropping the foot off the gas approaching stops. We were also having some stumbling during acceleration. We decided to look it up on Google to see if anyone else was having the same problems. We came across the following link;

http://www.ffcars.com/forums/17-factory ... 023?page=1

To save you some time, here is a cut-and-paste of the thread writer's symptoms, and also what he found out concerning problems similar to ours;

"Curious if anyone else has the FAST EZ-EFI and if your having the same trouble as I am? Initially I thought it was a great upgrade but I have been having a continual intermittent problem of either the idle changing or it falls flat on its face and dies at stop signs. I have called FAST for help and they thought first I didn't have the butterflys set up properly but I did their setup and the problem persisted. Then they thought it was the IAC but refused to send me a replacement. I bought my own for $85 and the problem is still there.

My IAC is at around 16 at a 1% TPS which is what FAST told me it should be. The handheld will show the same numbers when the idle changes (2500RPM VS 800 rpm). I noticed if it idles fast, I can reset it by shutting down and restarting but I can't figure out the stumbling problem. When it kills at a stop, it won't start unless I floor it while cranking.

Any thoughts would be appreciated, especially if you solved a similar issue with one of these."

"Well, as others have said, it was definately running rich. I read up in the instructions and got back in the car and went for a long ride with many stops to adjust the handheld. As I watched the Actual AF against the Target AF I noticed the idle fuel was rich so I leaned that out a bit. The stumbling still persisted so I checked the Accel Fuel which was at 0. This really threw me off at first because the instructions don't give you the span for any of the adjustments which is a real negative of the manual in my mind. It was by total frustration that I pressed the down arrow, not expecting anything less than 0 when it went negative! A simple adjustment to -2 fixed 90% of the stumble and I settled in for now at -3 and it has not stumbled once. I don't know what the span is but 0 is not 0! The idle never went nuts so I'm crossing my fingers the computer was just trying to burn all that extra fuel when that problem happened and that I fixed it now."

Once we followed the poster's advice, all of our stumbling during acceleration and stalls during stops ceased. The car started easily, idled very smooth, good acceleration and a noticeable power increase. We were very happy with the performance of the EFI system. Based on the fuel pounds/hour readout on the handheld, we are getting 25 mpg at 65mph. This mpg figure is obviously an instantaneous reading, and does not take into account acceleration, braking and sitting idle at stops.

Now that we had a working system, it was time to come up with a better solution for the throttle body adapter plate. Our first adapter was working OK, but it just was not optimized for a smooth flow of air from the 4-barrel throttle body into our 2v converted log head. With the throttle body removed, I took measurements for horizontal clearance from the CI aluminum valve cover and vertical clearance from the hood. I decided to start from scratch with a 6"x6.5"x1.5" thick chunk of aluminum. I located and drilled the holes for the throttle body and the intake. I recessed the holes for the intake manifold to sink allen head bolts down into the adapter. I then marked the openings using gaskets and milled out a beveled hole. I milled the outside edge on the drivers side to fit along the valve cover. To keep from having the world's heaviest carb adapter, I milled the other three sides. Now I have the world's second heaviest carb adapter.

Installed the new carb adapter and it absolutely fit like a glove! I have about 3/16" clearance from the valve cover and about 1/2 clearance from the hood. The 2v opening is about 1/2" off from center of the 4-barrel opening, but the 1.5" thick aluminum allows for ample bevel to smooth flow the intake fuel/air. It is certainly far superior to our original 1" high adapter with the 2v opening offset all the way to one side without beveled sides.

Got the car running with new adapter and found a huge increase in low end power and much better acceleration. Not really a surprise, considering our original adapter, but very nice increase in performance. Overall, very happy with the FAST EFI system. We plan to have the car dyno-tuned very soon and will post the results.

I will try to figure out how to post some photos of this installation to this thread. Anyone who can't wait that long for images, please email me and I will forward them directly to you.

Mark Hagen
markjhagen@hotmail.com
 
Wow that was a lot of work but well worth it apparently. You just created a path for others to follow and saved them a lot of time and frustration.
Looking forward to the dyno numbers.
 
hotrodguy":1d8p6px0 said:
Others might check out the EFI from FI Tech

The smallest unit from FITech has four injectors, and is rated for up to 450HP.
http://fitechefi.com/default.asp.pg-GoStreetEFI
May be too large for the small block six (200/250) but not for the 300.

The FAST EFI system the OP is using has only two injectors.
http://www.fuelairspark.com/fas/ez-efir ... ystemhtml/

Of course, $795 for the FITech as opposed to $1337 for the FAST might make it easier to take a chance on.
 
A 4 into 2 adapter plate, will work , also the FI system will slow down the fuel at lower rpms . I have an email into FI Tech to see what they have to say. I am building a 250 pure drag motor , turbocharged on E-85. I have no idea if their system can work under this situation.
 
The $795 system from FITech doesn't handle the ignition, and won't work with boost.
They have other systems that will work with boost, but are more expensive.

I may consider the FITech (Holley is coming out with a cheaper system to compete)
for my Crossflow when I get around installing it.
 
JackFish":2o4hr8wf said:
Thanks for sharing your experience. (y)

I'm wondering if the Fast system works with the DS2?

The FAST installation manual says another source for RPM signal is the negative side of the ignition coil in a traditional dwell controlled inductive ignition system. To use this RPM signal, you can use the supplied FAST RPM Module. Not totally familiar with the DS2 system, but this may be an option.
 
I always enjoy reading about these "plug & play" EFI systems. Of course all of their marketing material presents them as easy to install, but I've never actually seen one actually plug and play. ;)
 
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