Hi guys and gals, this is my first post on this forum. I hope I'm in the right place! I am old school in my knowledge and know how when it comes to vehicles, these computer run cars, I have no idea what im talking about!

My partner recently bought a BF Falcon dedicated gas (ex taxi). It has a suspected blown head gasket. Rather than replace the head gasket he has decided to put another motor in it. The replacement motor is a petrol motor. He wants to run lpg through this motor.

Now, me not knowing much about modern systems, i would have thought that you would need to change at the very least the manifold or injectors to run gas through a petrol engine. But he is telling me that the computer will do what the computer does and the only thing he needs to change is spark plugs.

So my question is, is it really that simple? Or is this little venture going to turn into an epic quest? Do i need to warm up the "I told ya so"?
What are we going to have to do to the donor motor if anything?

Thank you in advance for reading this post, i am ready to learn!

as you i don't know that much either .... if it's a gas vapour setup .. then prob no, otherwise injection yes

From memory, the Egas engines have stronger rods to handle backfires, but there are plenty of dual fuel setups going around on petrol engines, so I wouldn't see that being an issue.
Externally, you'll notice the existing engine has a green rocker cover, and no provision on the inlet manifold for petrol injectors.
Swapping engines is most likely your best option, considering the existing engine probably has a lot of kms on it as well. Swapping the engine and using the existing manifolds and accessories is all you should need to do.