So i am working on my dream car finally, 1969 mustang fastback! It was originally a "m" code fastback. Purchased it due to NO RUST, but has not engine or tranny. I was thinking of doing a 4.6L or 5.4L DOHC in this car, but quickly found out how much mods are needed to fit the engine into the engine bay. I want a fuel injection engine in my pony, so took a look at the 5.0l and 5.8l EFI. Since my car was a 351 car, i figured go with the 5.8L. It seems like the best route is to go with a 93-95 ford f-150 lightning engine, swap out the top intake manifold with and after market or cobra R intake (good luck finding one of these). One concern I have with doing the 5.8L is the extra 2inch deck height, will this fit into the 69 engine compartment??? How many parts are interchangeable between the 5.0 and the 5.8? what are some computer electrical problems/issues i may come across when doing this swap? Also since this is a truck engine, what should i change in the engine before installing it to make the truck to car change. ie cam, pistons, crank shaft... etc???

thank you

Ryan

 

Truck engines just have different cams/intakes for the most part. Heads are the same(provided it has a 1/2" bolt hole), cams interchange, everything except for stuff like intakes, crank, rods etc. Good 351 EFI intakes are hard to come by. And yes a 351 will fit.

If you want a smaller, lighter engine you could just build a 347.

 

yeah i have read about individuals who bored out their 5.0l to a 347, but would rather stick with thicker walls. Just incase i ever do NOS or supercharger . So you would say taking the "good" 5.8l lightning engine out doing no mods and placing it into the 69 mustang would work fine??? ( i would however place a after market intake top on it to change the side of air filter)

I just don't want to do all this work and get a "truck type power" in my car.

ryan

 

It'll fit

 

someone correct me if im wrong but the upper intake on the efi 5.8 is interchangeable with the 5.0 one so you could just get any aftermarket/gt40/cobra upper intake and itll work with your stock lower one, i would maybe do some cleaning up of the lower intake though if your sticking with the stock one just to help flow a bit, also didnt the lightning motors have gt40 heads? if so then your in real good shape, change out the cam and your golden, also im pretty positive the rods on the truck motors are stronger, sounds like a good plan to me

 

The 351W was a factory option in '69 (my favorite year).

You can use almost any 351W engine, and put EFI components on the top. You don't have to pay the high price of a hard to find Lightening motor.

If the engine is not too radical, you can use the factory parts. But it doesn't take much to exceed the capabilities of those parts. If you want decent power, you might consider aftermarket EFI. It's expensive to start with. But it ends up being cheaper because you don't have to upgrade anything.

If you want something that looks sort of stock, but is actually high end EFI, consider Mass-FlowEFI.com It uses all Ford components for outstanding reliability. This system has an excellent reputation.

A new on on the market is Boss EFI from Retrotek. It looks like a carb, and has central injectors. Not as good as individual port injectors, but better than a carb. It's a fairly new product, but preliminary reports are good.

If you want something trick, check this out: VeryCoolParts.com I have a system similar to this, and I really like it.

 

That is true that any 351w block will work with the efi, it really depends what kinda motor you are going to be building, if just a mild 351w then any year would work, i belive around 69 were the strongest factory blocks, and the 90s era motors were rollers, double check on the years, a 351w roller motor would be nice, with one of those carb lookin FI setups, thatd be badass for sure

 

"Better than a carb" totally depends on the carburetor and EFI system you're comparing.

Most EFI is just about better than most any factory carb, but a good aftermarket carb will easily perform as well or better than even the top dollar aftermarket EFI systems.

If you really know how to tune a carb, it's the best way to go for performance, and a lot cheaper, if you don't REALLY know how to tune a carb then EFI.

Edelbrock has a couple newer systems out, the Pro Flo 2, and the newer XT. Complete kits that perform well. Top of the line would be something like FAST XFI.

 

Boring out the small block Ford only gets you a few cubic inches. The 347 is stroked 302 bored 0.030 over.

You may be hard pressed to find a low mileage 5.8L Lightning motor since they haven't used those in awhile Building a 5.8L block and a 5.0L block EFI motor will be about the same effort, though it'll be cheaper going the 5.0L block route.

 

You and I have the same car in mind as a "dream car." I've wanted a 69' fastback since i was a kid and eventhough I have a 72' coupe right now doesn't mean that it has been forgotten. Some day... But in relation to the engine, I would probably just stick with the lightning's engine (if that's the one you end up getting) because that it a badass setup as is. The lightning trucks are crazy fast and efficent for being race trucks and really that engine is more setup as a fast and beefy "car" engine than a truck engine what with the factory performance parts put into it and all.