Wisconsin VH4D carb/fuel injection swap

[BobbingAround]

Same thing...about to pull my hair out with this VH4D. One minute an empty fuel filter and the next minute fuel is dumping out of the carb all over the top of the engine. CNC cut a couple phenolic spacers that I will try next. I have never seen a mess like this. A very basic fuel injection setup would be great for these old engines. I was thinking y'day that a different intake/exhaust design (separate) might help.

Wonder if we could get a fuel injector to work with a high-frequency switching MOSFET then drive the injector through the MOSFET with a small raspberry pi at a static rate to achieve an AFR of 14.7. at max torque RPM...I think it was 2200RPM.

I see speeduino is a thing. Crazy that making a fuel injection system seems a more viable source for fuel control than an old carb with a few jets. I won't spend the next 2 days chronicling all I have tried and the number of carbs /cleanings I have been through already.

Fuel injector driven by fully variable injector tester and an AFR gauge then adjust manually for optimum AFR. $5 rpm gauge.

 

[T-rustyfix]

Sounds great! Would you be interested in the fuel injection mount I fabricated for the Vh4d?

 

[jonesallu]

I just ran across this thread. t-rustyfix, you've done some incredible work with your fuel injection project. I'm impressed. I'm headed there myself, but with the Ford V-4 1.7L. I realize this is too late, but a few things. Doesn't the fuel injector need 5VDC, not 12VDC? You don't need a crankshaft position sensor, you can get that from your distributor and go from there. I've been looking at the Megasquirt and the standard GM computer for earlier TBI injection (can't recall the computer number, but they're plentiful, cheap and easy to reprogram), etc. I'm sorry if I missed it, but what pressures were you running to the injector? The compete solution is the Holley Sniper single barrel TBI to replace the Autolite 1100 carb. An adapter to mate it to your manifold looks like it could be fabricated with reasonable effort. I've talked with their engineers and everyone is using it for a myriad of different applications. They described how to insert fuel curves to tune it down to such a low displacement engine. The kit is very expansive (at least to me, and without the hot fuel pump setup) so I've asked for one for my birthday from my wife. We'll see if that gets traction. There's a company in Michigan that deals in low displacement TBI setups too. If you're interested, I can forward you their info. They are very knowledgeable. Good luck with your future FI endeavors, it sure seems like you were getting close to a solution.

Best,
Al Jones
Brookings SD

 

[2bobcats]

Have had a few vh4d on 600 bobcats. Did you try an electric fuel pump.

 

[T-rustyfix]

I had 150 psi going to an injector from a Honda Fit. It was rated for 12v, but not constantly. It ran ok for awhile. I adjusted fuel pressure and throttle to find proper AFR, but it wouldn’t react properly to governor changes under load. Finally, it began to burn out injectors. I’m not electrically savvy. I’m sure someone who knows more than me could figure it out. Thanks for the interest on this thread. Let me know what y’all find out!

 

[2bobcats]

I should have said to use the electric fuel pump with a carb. What is the weather like where you live as air cooled engines don't do real well in hot weather