Fhead Fuel Injection

The 3B has a pretty good running fhead, but we are going to see how much better it runs, if at all, with fuel injection. In reality it probably does not need it, but i like fun projects.

it uses a 1barrel GM throttle body, from the late 80's 2.5 iron duke 4cyl. These old TBI systems are super simple, bullet proof and easy to dial in.

The stock distr needs to have a electronic pickup installed and the weights removed, as all the timing will be done by the computer. I used a new replacement electronic dist, so only the weights were removed.

I got the harness, adapters and computer from Hamilton FI, so after its running, we will datalog it, send the data over the hamilton, and they will update the chip with engine specific programming.

I am getting close to startup, elec fuel pump, filter, all new feed and return lines are installed, temp sensor and O2 sensor are installed, and stock linkage is connected to the TB

Im using the stock tank, and feeding the return in from the bottom drain fitting, hoping it will work, otherwise i will have to install a bulkhead fitting on top of the tank and route the return there.

 

Awesome!!! I so hope this works out for you!

 

Yep, awesome. Watching with great interest! Bill knows those GM systems inside and out.

 

I dig it. On my CJ5, I've been learning about a Buick GN 231Turbo V6 SFI. Your correct that the ECM & Chip does all the work , after TPS & IAC settings are made. I also have to deal with injectors. To my understanding, the fuel return line is an emissions requirement for fuel vapor ? I think you will have some sort of siphon created , with the raw fuel , if you connect to the bottom of the tank ?
On your 3B, is the tank under the seat ? If so, is it fairly easy to get at the top?

One other thing to consider is installing the Temp sensor directly into the block or thermostat housing.I think your ECM may want that ? I did it the way you have done but had to change it 'cuz it was not getting the correct reading?


Any way...Very Cool project . Please let us know how you are making out.

 

Liking this project. Hope it works out. Looks like a clean install so far.

Part numbers and a detailed write up would be useful for those who follow.

 

I'll be interested to see how this works.

 

Bill from Hamilton FI, has basically put every bit of info you need in a post over on in the IH forum, Binderplanet
only thing i dont think is there is the single barrel throttle body. But as said, that is from a late 80's GM 2.5

Parts Needed For The Gm TBI Conversion

 

this is the exact TB, looks like there are 2 different ones, dont know any info about the other one.

Advance Auto Parts -throttle body

 

Not sure if it matters, but the return line for the tank in my CJ-6 (factory diesel engine) is in the top of the tank while the pick up is on the bottom. I do have a fuel delivery issue occasionally with my 3A and it comes in from the bottom using the drain. Hard to say if it's related to the return location.

 

got it running yesterday, started on first try, and nothing caught fire.. i still have some adjustments to check and some data to log once its driveable, but it feels better and sounds better already.

 

That’s awesome!!

 

DUDE! Awesome!!!!!!!

 

So far how much time, funds and beer is involved?
$
$$
$$$

 

I probably have $1200 into it, but i like new parts, all parts and sensors are new or rebuilt. 10-12 hours and beers were not counted,

 

Knocking off all the little things, got all the guts tucked up under the dash nice and neat. love the extra height under the dash.
all the lines and wires secured, and if my air cleaner shows up tomorrow, i’ll Be able to take it for a ride.
I thought this was cool, I’m going to take AC trigger, which raises the RPM a little to compensate when the AC is on, and run it to the York OBA, so when the compressor is turned on, the RPM will jump up to a set point

 

Outstanding Paul! Outstanding. Thanks for sharing this.

 

I am Impressed , Sir. She really purr's ! I believe you just wrote textbook . Great, Great Job !

 

Well done, sir!