Ive been doing some research on the FiTech EFI and Holley Sniper I posted in the FiTech thread and figured I would drop in here as that is in the 60's section.
Both units are designed to bolt to standard 4 barrel intakes and replace carbs. They have internal ECUs so it is a clean install. Wire O2 sensor, temp sensor, coil (-) for an ignition signal, power, ignition, ground. Both have built in regulators which eliminates the need for an external one. FiTech says it will support engines up to 400HP with its smallest unit. Holley says 600.
For me the appeal is in the self tuning with the wide band O2 as tuning seems to be the gripe of many who have installed the GM units based on my searching.... and the ability to swap it over to future V8 in my 40 or another vehicle if I go back to a carb. By the time you factor in a Painless harness its close in cost to building your own. 4 wires is less to trouble shoot and much cleaner. I had a thought for an adapter (below) or using an Offenhauser intake.
The initial concerns with FiTech are reliability/support and heat on being over an I6 (also a concern with Holley). FiTech is a new company of former OE/aftermarket engineers and according to videos, using a lot of OE components to build these and keep the price down.
"FiTech, a new American company based in Riverside, California, is the brainchild of Ken Farrell and Jeremy Schmidt. Both gentlemen bring to the table decades of aftermarket and OE fuel-injection design and manufacturing experience"
There is a question in their FAQ about heat on a 2F
"benjamin September 7, 2016 at 10:39 pm Reply
I’m running an inline 6 (2F) in my FJ40 and upgrading to fuel injection. Has the FiTech unit been designed to protect itself from the heat being mounted directly over an exhaust header? My concern would be that the heat might affect the electronics. Thanks!
Bryce - FiTech Tech Pro September 13, 2016 at 8:38 pm Reply
We have not had any heat related issues with our ECU’s. Our systems are built to take the heat of an engine compartment."
Probably would have done a heat shield myself just for good measure.
I reached out to Fitech. They say the minimum for their 400HP kit is 150HP (however they have been open about padding their ratings in the other direction with the 400HP being able to handle 450.) It will flow up to 750CFM. Holley says the Sniper kit (600HP) has a minimum of 200HP.
I pressed both of them about CFM and displacement because its not like a 3.9L F or 4.2L 2F are small engines, they are just designed to make torque. Both kept defaulting to the HP numbers rather than CFMs. FiTech is definitely the smaller of the two and the more likely option to work. I thought that after seeing it run on 4 cyl engines which presumably move less air at idle than our 3.9/4.2Ls, but Im not going to buy one just to try (maybe I can convince my brother to get one for his 289 Mustang).
A different tech than the one who told me the 200HP limit at Holley replied to an email inquiry:
"There is a 4, 6 , or 8 cylinder setting in the programmer, and also cubic inch setting. Our system will be fine. It will control the fuel.
Sincerely
Woody"
Then I got more info from FiTech. As mentioned above, my thought was the limitation would be with the injectors and how little they could flow at idle. However a 3.9/4.2 moves as much volume at idle as other higher HP engines with comparable displacement.
This is what FiTech told me:
"Hi
the system would start and run fine, but with that large of the throttlebody. When you go to wide open throttle the large dump the air. You could possibly lose all intake velocity and it will fall on its face momentarily and probably even backfire through the intake. This is why we have the minimum horsepower requirement."
Does any have any thoughts on this? This would also be true for the Holley contrary to what Woody said.
I like the FiTech and Holley units because they are not specific to these size motors like a custom built system. If I wanted to go back to a carb I could sell the FiTech/Holley or use it on something else so there was less risk in the investment.
The other option I am seeing for self tuning is EZ-EFI which has a kit designed for inline 6 Jeeps. It has been adapted to other engines such as a Ford six as seen here with some cool photos of a custom adapter linked down the thread. This kit is more expensive, is a more complicated install and Ive found a lot more negative reviews on how "self learning" it actually is. It also has an external water tight ECU which would have to be mounted.
EZ-EFI did reply to me when I inquired about their kit designed for Jeeps that I have also seen on Ford I6's.
"Ryan,
We could run that kit on the Toyota engine I'm sure. The adapter that comes in the kit for the Jeep intake obviously wouldn't work, but you could adapt it to the Toyota intake, or come up with a different style. Our throttle body systems us a 4150 flange base. The Jeep kits are limited to about 350HP and flow upto 1250 CFM. We offer them with or without universal fuel pump kits for both inline and intank applications.
Let me know what you think and if you need more information or help placing an order, as we can set your up directly."
It looks like the throttle body they use for the Jeep kit is different than the 4150-style Throttle Body they say supports up to 650HP as this only supports 350HP.
To mount any of these I was looking for either an Offenhauser intake or considering making an adapter. Stacking adapters would work too Im sure. Downey's then Webber to 4bbl.
My concept would be 2" high out of Aluminum. Id cut the outside profile and center oval on our waterjet at work. Mill the rest in 2 set ups.
Fuel pump would be straight forward with a return to a T in the vent on the stock tank as others have done on here.
Im still interested if anyone has any insights.
Both units are designed to bolt to standard 4 barrel intakes and replace carbs. They have internal ECUs so it is a clean install. Wire O2 sensor, temp sensor, coil (-) for an ignition signal, power, ignition, ground. Both have built in regulators which eliminates the need for an external one. FiTech says it will support engines up to 400HP with its smallest unit. Holley says 600.
For me the appeal is in the self tuning with the wide band O2 as tuning seems to be the gripe of many who have installed the GM units based on my searching.... and the ability to swap it over to future V8 in my 40 or another vehicle if I go back to a carb. By the time you factor in a Painless harness its close in cost to building your own. 4 wires is less to trouble shoot and much cleaner. I had a thought for an adapter (below) or using an Offenhauser intake.
The initial concerns with FiTech are reliability/support and heat on being over an I6 (also a concern with Holley). FiTech is a new company of former OE/aftermarket engineers and according to videos, using a lot of OE components to build these and keep the price down.
"FiTech, a new American company based in Riverside, California, is the brainchild of Ken Farrell and Jeremy Schmidt. Both gentlemen bring to the table decades of aftermarket and OE fuel-injection design and manufacturing experience"
There is a question in their FAQ about heat on a 2F
"benjamin September 7, 2016 at 10:39 pm Reply
I’m running an inline 6 (2F) in my FJ40 and upgrading to fuel injection. Has the FiTech unit been designed to protect itself from the heat being mounted directly over an exhaust header? My concern would be that the heat might affect the electronics. Thanks!
Bryce - FiTech Tech Pro September 13, 2016 at 8:38 pm Reply
We have not had any heat related issues with our ECU’s. Our systems are built to take the heat of an engine compartment."
Probably would have done a heat shield myself just for good measure.
I reached out to Fitech. They say the minimum for their 400HP kit is 150HP (however they have been open about padding their ratings in the other direction with the 400HP being able to handle 450.) It will flow up to 750CFM. Holley says the Sniper kit (600HP) has a minimum of 200HP.
I pressed both of them about CFM and displacement because its not like a 3.9L F or 4.2L 2F are small engines, they are just designed to make torque. Both kept defaulting to the HP numbers rather than CFMs. FiTech is definitely the smaller of the two and the more likely option to work. I thought that after seeing it run on 4 cyl engines which presumably move less air at idle than our 3.9/4.2Ls, but Im not going to buy one just to try (maybe I can convince my brother to get one for his 289 Mustang).
A different tech than the one who told me the 200HP limit at Holley replied to an email inquiry:
"There is a 4, 6 , or 8 cylinder setting in the programmer, and also cubic inch setting. Our system will be fine. It will control the fuel.
Sincerely
Woody"
Then I got more info from FiTech. As mentioned above, my thought was the limitation would be with the injectors and how little they could flow at idle. However a 3.9/4.2 moves as much volume at idle as other higher HP engines with comparable displacement.
This is what FiTech told me:
"Hi
the system would start and run fine, but with that large of the throttlebody. When you go to wide open throttle the large dump the air. You could possibly lose all intake velocity and it will fall on its face momentarily and probably even backfire through the intake. This is why we have the minimum horsepower requirement."
Does any have any thoughts on this? This would also be true for the Holley contrary to what Woody said.
I like the FiTech and Holley units because they are not specific to these size motors like a custom built system. If I wanted to go back to a carb I could sell the FiTech/Holley or use it on something else so there was less risk in the investment.
The other option I am seeing for self tuning is EZ-EFI which has a kit designed for inline 6 Jeeps. It has been adapted to other engines such as a Ford six as seen here with some cool photos of a custom adapter linked down the thread. This kit is more expensive, is a more complicated install and Ive found a lot more negative reviews on how "self learning" it actually is. It also has an external water tight ECU which would have to be mounted.
EZ-EFI did reply to me when I inquired about their kit designed for Jeeps that I have also seen on Ford I6's.
"Ryan,
We could run that kit on the Toyota engine I'm sure. The adapter that comes in the kit for the Jeep intake obviously wouldn't work, but you could adapt it to the Toyota intake, or come up with a different style. Our throttle body systems us a 4150 flange base. The Jeep kits are limited to about 350HP and flow upto 1250 CFM. We offer them with or without universal fuel pump kits for both inline and intank applications.
Let me know what you think and if you need more information or help placing an order, as we can set your up directly."
It looks like the throttle body they use for the Jeep kit is different than the 4150-style Throttle Body they say supports up to 650HP as this only supports 350HP.
To mount any of these I was looking for either an Offenhauser intake or considering making an adapter. Stacking adapters would work too Im sure. Downey's then Webber to 4bbl.
Fuel pump would be straight forward with a return to a T in the vent on the stock tank as others have done on here.
Im still interested if anyone has any insights.
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