Why Can’t I Put BMW Fuel Injection on a 1974 Scout?


I know this sounds insane but why not? I’ve been playing with(others call it rebuilding) the Eddlebrock Performer series carb that was on the Scout when I bought it and all I can think about is how simple the BMW fuel injection is that I normally use.

pouring fuel down the scout
I know the new fuel injection stuff is crazy complicated but why can’t I go visit Autobahn Dismantling in El Cajon, CA and buy the wiring harness, ecu and throttle body from an older BMW V8 engine. Maybe a 540? 

It seems like it would be pretty straightforward… seriously. Has anyone done this? And yes I know companies like Holley and MSD sell fuel injected carburetor kits but they are like $2200. And you still need to rig it up to your engine.

So why not weld a BMW throttle body to a spacer plate that bolts to the intake manifold?

bmw throttle body
Add the trigger wheel to the crank matching up top dead center. Make a quick bracket to hold the sensor.

crank trigger
Add an O2 sensor to the exhaust.


And now the hard part. drill out the intake manifold for the fuel injectors. A beefier aftermarket fuel rail could be cut up and rewelded to get the proper spacing to hold the injectors in place

BMW single fuel injectorOf course the intake manifold will also need to be tapped for a fitting to hold the idle control valve.

Put some fresh fuel lines on that handle a high pressure fuel system and install a new high pressure fuel inspection pump to the tank.

fuel pump
Then you power up the wiring harness/ ecu and fire it up!

BMW Wire harness
What am I missing? Volume difference of the two engines? Can’t I just do some basic math and use larger injectors? 

Throttle body size? Its hard to imagine I need that much larger of one given my lower RPM limits. 

Would Megasquirt be easier?


  1. So%y Bill, It is megasquirt that you are talking,about, using factory parts to install fi on a a different motor. You still have to tune it and that’s where megasquirt comes in.

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