I am interested in replacing the original 240 inline six with a 300. I would like to keep the carburetor and ignition system (distributer). I understand that the 240 head is a direct bolt-on for the 300. Or could I just use the manifold off my 240 to bolt directly onto the 300?

Mostly what I am confused about is if I will be able to install this engine with carburetor and distributor with no computer module. I do not have the 300 yet, but have an opportunity to buy one. The 240 is in the machine shop being cleaned and magnafluxed.

Thanks
Nate

 

a 300 with a carb? yep they were around long before fuel injection. your 240 manifolds will bolt right on (you can swap the head if you desire, I don't remember exactly how much, but it gives the compression a good boost) although just using manifolds off the 240 would be easier.

it sounds like you are running the 300 as a temp engine while rebuilding your 240?

 

No compression boost when putting a 240 head on an EFI 300 short block. The two heads have the same size combustion chambers ( or very very close to the same ) . The EFI chambers are just a fast burn design.

You can bolt the 240 manifolds onto the 300 EFI engine. But you'd be better off running the EFI dual exhaust manifolds with your 240 intake. The EFI exhaust manifolds are like a pair of cast iron shorty headers. They flow much better then the stock 240 exhaust manifold.

And you can run the 240 distributor but you'll need to do some tuning to the mechanical advance in the distributor. Because of the 300 EFI's fast burn combustion chambers you need less total timing.

The only other issue you might have is the fuel pump. The EFI 300's don't run a mechanical fuel pump. Their blocks have the boss for it but it's not opened up. So you will need to open up a hole in the block for the fuel pump. Or better yet just run a small low pressure electric fuel pump.

 

Thanks a lot for the info, I am going to look at the motor tomorrow. Are the motor mounts also the same and it should bolt up to my t18 transmission? Also I noticed part of my clutch linkage was attached to the motor,

1968 F-250

And yes I am considering running this engine temporarily or permanently if it runs good enough.

 

thanks for straightening that out, I take it was it only the carb'd 300's that got the compression boost?

ndamccan- my 300 is an efi and I don't remember it having the pivot on the block. im guessing that there is probably a bracket?

 

Yep the carb'd 300's get a 0.5 bump in the compression ratio by swapping on a 240 head. So if it has 8.5:1 it goes to 9.0:1.