It WAS awesome. I drove it a couple miles, it was night and day. I want it back. We will get there.
Affordable Fuel Injection (1 Viewer)
- Thread starter ptefj40
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Talked with Norm again. Holy crap he is tired of talking to me.
Supposed to have a HEI distributor on the way. We will see how that plays out.
Supposed to have a HEI distributor on the way. We will see how that plays out.
Post up some pics of the connections on yours. Does it have a plug that matches the harness?
Jumped the gun a bit ...there is an adapter plug that matches the harness, so I just need to splice into that.
There is a 'tach' and 'batt' connection that I don't know what to plug into it. Is the batt plug constant or switched 12v? I'm guessing 12v switched. Is the tach connection just for a tach or does something else go there?
There is a 'tach' and 'batt' connection that I don't know what to plug into it. Is the batt plug constant or switched 12v? I'm guessing 12v switched. Is the tach connection just for a tach or does something else go there?
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The tach is only used if you have a tach, otherwise leave it alone. The BATT is switched 12V.
Keep this handy, but ignore the advance portion:
http://performancedistributors.com/wp-content/uploads/2013/06/GMDUIInstructions.pdf
Keep this handy, but ignore the advance portion:
http://performancedistributors.com/wp-content/uploads/2013/06/GMDUIInstructions.pdf
Thank you very much.
So how do you get the distributor in? The studs on the top of the side cover that hold a heater hose are in the way.
it won't drop in, the base of the distributor hits one of the studs.
Remover the stud?
Also, per those instructions, spark plug gap should be at .055" This applicable to a 2F? Never heard/read that much gap on these motors.
Thanks
it won't drop in, the base of the distributor hits one of the studs.
Remover the stud?
Also, per those instructions, spark plug gap should be at .055" This applicable to a 2F? Never heard/read that much gap on these motors.
Thanks
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got the distributor in....took that stud out.
This is a good resource for the DUI install.....055" seems to be the consensus...and of course I've got to buy new wires....of course there's another wasted day
DUI/ Hei installation... Plugs?wires?
This is a good resource for the DUI install.....055" seems to be the consensus...and of course I've got to buy new wires....of course there's another wasted day
DUI/ Hei installation... Plugs?wires?
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Get the live wires
I’d stick with the factory gap settings. There’s no real benefit to increasing gap unless you’ve done other modifications to the engine. All you’re doing is making the ignition system work harder for very little if any gain. These are tractor engines after all. At most maybe gap it to .044 like the 3FE engines.
Edit: FWIW mines gapped to .032 running headers and I’m averaging 18-20mpg on my 2F. Fuel injected via Megasquirt
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That’s the first I’ve heard of mileage gains by any EFI on a 2F
What’s the rest of the setup like? tires? Load? Gears?
Ordered.
235/75/15s. 4.11gears. Pretty much stock. The mpg gains is from running slightly higher AFRs throughout the cruising rpms.
The 2F responds well to running between 15.5-16.5 AFR at cruise. I’ve had it up to 17s but the EGT starts to climb higher than I’d like at that point.
An agressive fuel cut during decel and coasting helps a bit as well.
I averaged 16-17mpg prior to the Megasquirt install for reference.
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Can you explain this in salesman terms that I can understand?
Also is this a 40 or 60 you have?
I went from 13.5-14 down to 11.5-12 with a loaded, heavy 60 with 33’s and 3.70 gears.
On my 76 40. I’m basically running lean at my cruising speeds. With a wideband 02 sensor I can dial in a particular air fuel ratio (AFR) at a particular load. Stoich for gasoline is 14.7:1. Anything below stoich you’re running rich anything above you’re running lean.
Using the logging function on my laptop I plotted how much time the engine spends at a particular load and rpm. Basically how I drive my vehicle. Since I spend the vast majority at cruising that’s where I focused my tuning. I’ve leaned out those areas where I spend the majority of my time to improve my mileage.
15.5-16.5 afr is as lean as I’ve pushed the 2F engine. Any leaner and my exhaust temperatures start to soar. For my engine its a good compromise as it still make good power but I get a little better mileage. Of course how this works in the long term I’ve yet to see. I’ll pull the head at 20k and see how the valves and pistons are holding up.
Deceleration fuel cut. During deceleration the computer reduces the amount of fuel being delivered by the injectors by a certain % or shuts it off entirely based on load.
With a steady right foot I’ve tuned it where if I left off the gas slightly it’ll shut off the injectors.
Hopefully that helps. There’s other tweaks I’m working on to improve the performance. But again it’s like polishing a turd. One can only do so much. But I enjoy this aspect of engine tuning.
And YMMV. I wouldn’t attempt this without a good wideband 02 and EGT and knock sensor. Your fuel and ignition maps need to spot on as well before attempting to play around with your AFRs. You can easily blow your engine if you make a mistake.
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Yeah I’m just going to keep filling mine up. The fire and forget that the pre programmed AFI is not the most efficient but it keeps me from having to think about all that.
I did advance my timing from 0* to 13* recently.
I have no ping and it seems to be a bit more peppy but I also noticed its running a bit warmer than it did before
I did advance my timing from 0* to 13* recently.
I have no ping and it seems to be a bit more peppy but I also noticed its running a bit warmer than it did before
You are welcome to send me your afi chip and a extra chip with it. I can modify the afi program for you and try and get u some better mpg numbers. But I remember you telling me your ecu was not easy to access so its kind of a pain for you to do on your rig.
I spend waaay too much time thinking about this stuff. 
It’s the years of tuning 7Ms and 2JZs kicking in. I just can’t leave well enough alone. Definitely a character flaw. 
It’s the years of tuning 7Ms and 2JZs kicking in. I just can’t leave well enough alone. Definitely a character flaw. 
Great reading here. My '78 FJ40 with AFI TBI gets about 12 - no better. I"m at 7000' elevation and run 33s. About what it got before with the carb, but vastly better driveability across all temps/conditions.
I'll probably just put gas in it and drive it. I suspect it's not running terribly lean (based on exhaust smell, spark plug color, and mileage), but if that protects my valves, etc. that's fine with me. Gas is cheap, relatively speaking.
I'll probably just put gas in it and drive it. I suspect it's not running terribly lean (based on exhaust smell, spark plug color, and mileage), but if that protects my valves, etc. that's fine with me. Gas is cheap, relatively speaking.
