- Jun 6, 2001
- 1,967
- 6
- 81
Initially I built the motor with dual Weber DCNF carburetors and a Bosch 019 distributor. I got tired of the carburetors and/or couldn't figure out how to adjust them properly.
This is it running at it's best.
I had read about Megasquirt, which, if you are unaware, is a standalone ECU. I initially planned to use a MS1 as it had more than enough features for what I needed. I started buying parts to begin the conversion.
Throttle body from a Ford Contour, fuel injectors from an Escort, coils from a GM truck, and a MAP sensor from a 3800 GM V6. All sourced from a local junkyard.
Seeing as how I had 2 carburetors and was going to a single throttle body I had to figure out a way to mount it. As the Beetle originally only had a single center-mount I decided to try to replicate that.
Crude Fusion 360 drawing before having taken any measurements of the motor.
After measurements
I am not a welder so here it is in all of it's hideous glory.
Powder coated black and mocked up in the engine bay. I think I ended up trimming the long lower tubes. I also forgot to put in the IAT sensor which has since been added.
With throttle body and cable.
Next up was figuring out how to mount the injectors. There are kits floating around the internet that people scavenge from the fuel injected Mexican Beetles but it was more than I wanted to spend. I got a set of stock dual port intakes, some injector bungs, and fuel rail from ebay.
Milled intake for bungs.
Fuel rail cut to length, drilled, and counter-bored for injectors.
Test fitting both sides for clearance.
More ugly welding, this time of the bung into the manifold.
Bracket to hold down the rail. This is the best idea I could come up with so I wouldn't be stuck with this injector length.
Also began working on the trigger wheel, which tells the ECU where the engine is in it's combustion cycle.
36-1 wheel
Tacked to backside of crankshaft pulley.
Crank position sensor mounted behind pulley. This was from a V6 Ford Probe.
Made a temperature sensor to be used for warm up enrichment. This mounts on the cylinder head near the intake port. This was the recommended method by other aircooled engine users.
More fuel system stuff
Fuel tank outlet/return T
Fuel pump mounted. Overkill Walbro 255.
And then finally strictly due to the price I ended up not using a Megasquirt. I came across a daughterboard that mounts to an Arduino Mega called Speeduino. It was around $100 to buy the PCB and all the components and then I soldered it together.
Speeduino V0.3.4 here without the VR conditioner mounted.
And here is the first run.
I should have taken more pics but there you have it. I'm currently working on cleaning up the wiring and adjusting the tune. I'm slow to get anything done
Thanks for reading
TL;DR
What once was carbureted is now fuel injected.
I had read about Megasquirt, which, if you are unaware, is a standalone ECU. I initially planned to use a MS1 as it had more than enough features for what I needed. I started buying parts to begin the conversion.

Throttle body from a Ford Contour, fuel injectors from an Escort, coils from a GM truck, and a MAP sensor from a 3800 GM V6. All sourced from a local junkyard.
Seeing as how I had 2 carburetors and was going to a single throttle body I had to figure out a way to mount it. As the Beetle originally only had a single center-mount I decided to try to replicate that.

Crude Fusion 360 drawing before having taken any measurements of the motor.

After measurements

I am not a welder so here it is in all of it's hideous glory.

Powder coated black and mocked up in the engine bay. I think I ended up trimming the long lower tubes. I also forgot to put in the IAT sensor which has since been added.

With throttle body and cable.
Next up was figuring out how to mount the injectors. There are kits floating around the internet that people scavenge from the fuel injected Mexican Beetles but it was more than I wanted to spend. I got a set of stock dual port intakes, some injector bungs, and fuel rail from ebay.

Milled intake for bungs.

Fuel rail cut to length, drilled, and counter-bored for injectors.


Test fitting both sides for clearance.

More ugly welding, this time of the bung into the manifold.


Bracket to hold down the rail. This is the best idea I could come up with so I wouldn't be stuck with this injector length.
Also began working on the trigger wheel, which tells the ECU where the engine is in it's combustion cycle.

36-1 wheel

Tacked to backside of crankshaft pulley.

Crank position sensor mounted behind pulley. This was from a V6 Ford Probe.

Made a temperature sensor to be used for warm up enrichment. This mounts on the cylinder head near the intake port. This was the recommended method by other aircooled engine users.
More fuel system stuff

Fuel tank outlet/return T

Fuel pump mounted. Overkill Walbro 255.
And then finally strictly due to the price I ended up not using a Megasquirt. I came across a daughterboard that mounts to an Arduino Mega called Speeduino. It was around $100 to buy the PCB and all the components and then I soldered it together.

Speeduino V0.3.4 here without the VR conditioner mounted.
And here is the first run.
I should have taken more pics but there you have it. I'm currently working on cleaning up the wiring and adjusting the tune. I'm slow to get anything done
Thanks for reading
TL;DR
What once was carbureted is now fuel injected.