5.0 convert to carb

ks65stang said:

Can any 5.0 efi engine, besides the new ones be converted to a carb? What the best doner car thats cheap. I would like to buy running. What's needed to swap to carb besides the carb, intake and dizzy. This is going in my 65 but I posted here as this will be a super easy question for the 5.0 guys. Thanks in advance!

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Yes any efi engine can be converted to carb. Besides what you mention you would also need either a carb fuel pump and different lines or a bypass regulator to work with the efi pump. Carbs run at about 6psi.

If you want to run a mechanical fuel pump, you need the eccentric parts from a carb'd small block, and the timing cover from a carb'd small block. Not sure without checking years, but you may also need to change the cam retainer plate to clear the eccentric. They were different thicknesses depending on which eccentric and probably different thickness for the EFI engines. I'd say use the cam plate off the same engine you get the eccentric from, that way you know it's right.

Edit:
I'd bet you already know this, but just incase you didn't...
You need a front sump oil pan and pick-up, as well as making sure you use the correct imbalance weight for the engine you choose as a donor. If you use a roller cammed engine, they generally use a different distributor to cam gear.

If you use an Explorer engine with "P" heads, you must be careful on which headers you choose. Many are not compatible with the spark plug location unless you are prepared to do some custom mods. The Explorers have EFI set ups on them that are worth some money if you don't use them. I paid 75 bux for the entire EFI off an Explorer engine, which is pretty much normal, but I have seen people pay more. If you get at least that out of the intake and related parts, that will help recoup expenses on your project.

If you find a good running 86-92 HO engine (Mustang, Mark 7, and some T-birds), they have forged pistons from the factory. Starting in 93, the pistons went hyperutectic, which have some benefits, but are not as strong.
If the engine needs building and overbore, then the forged pistons don't mean any benefit at all.

Remember that not all EFI 5.0 engines are HOs!
Mustangs/Mark 7s are the sure bets, beyond that, many look the same, but are not, and there are differences in internal engine parts. No trucks are HO spec. If no one has swapped intake plates, HOs will say "5.0 HO", while passenger engines will say something more like "5.0 EFI".

We bought a low miles, but rusty, Mark 7 (HO and AOD) recently for 500 bux. Pulled the drivetrain and it functions perfectly. (We converted from carb to EFI though.)

Mustang5L5 said:

Not all mark 7 are efi 5.0 HO. I believe in 87-88, the base engine was a standard output 5.0 and the LSC got the HO. Around 88 or 89 it became standard in all

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HO was standard on all, but I don't know the first year.
Ford has a long history of putting the next new "high tech" engine into their top Lincoln, so I would put money that it was as early as possible. Even the Mark VIII got the 4v Cobra engine before the Cobra, as did the Mark III got the 460 before any other Ford. The list goes on.

Our donor was an 88 "Bill Blass", not technically LSC, even though I use LSC interchangeably with Mark VII often... force of habit. I do know that when they got HO, they were ALL HO.