[Innovator]

Will a 368 intake manifold fit onto a 472/500? I think I may have come across one. I would like to perform a MPFI conversion on a 472/500 using 368 components combined with a DIY EFI management system, such as MegaSquirt.

Also, as a side question: Could a 368 be converted into a 500 by boring out cylinders and using 500 internals and heads? My understanding is the casting is similar except for the bore?

 

[BRUCE ROE]

Will a 368 intake manifold fit onto a 472/500? I think I may have come across
one. I would like to perform a MPFI conversion on a 472/500 using 368 components combined
with a DIY EFI management system, such as MegaSquirt.

Could a 368 be converted into a 500 by boring out cylinders and using 500 internals and heads?
My understanding is the casting is similar except for the bore?

Hardly anything interchanges between a 368 and a 500. You can only add a dozen or so cubic inches
boring, then you run out of metal. Why waste time trying to convert a wimp 368 block when you
could start with a 500? Manifolds, I think you'll find the ports don't line up. The 368 is throttle body
injection, not port injection. The heads are very poor breathers. You can get a factory port injection
system for a 425 or 500. Then adapt the injector size and impedance to the EFI system you had in
mind. The 368 HEI will drop into a 500. Bruce Roe

 

[the APEMAN]

You CAN use a 368 manifold on a 500. I've done it. It will limit performance as port size is smaller. The engine will not be a gas mileage champion.

A better intake to look for would be one from a fuel injected 425 or 500. Those were made from 1976 or maybe 75 to 1979. They use port injection and can be setup for sequential via the Megasquirt.

The stock injectors are low impedance (high current) and will NOT work with the M-Squirt. Later injectors must be sourced.

Another possibility is a Ford (yes, I know:crybaby 460 F.I intake with an a-dapter kit. Apologies to Johnny Cash.

The 368 block underwent a diet and is plenty strong for stock but would not make it with 500 internals. They won't fit anyway.

368 was very well engineered at the time for gas mileage in a 4000 lb car. That makes it quite a bit different from the 500 which was designed to run like smaller engines but with crummy fuel and reduced emissions.

 

[Innovator]

I ended up pulling the 368 intake and throttle body. Yes, I did find out this is a TBI intake, not MPFI. Oh well, I picked the whole thing up for $25.

Can the 368 intake be modified such that the ports match in size? Is it even worth monkeying with this intake?

Additionally... I have a non-HEI ('68) distributor that has been converted to full electronic; Megasquirts only relate to the distributor by way of the tachometer signal, correct?