Eric3501

Long time lurker with a question. I am replacing the engine in my 1989 F-250 that has a 5.0 engine. I was wondering if this engine will work, ( with modifications of coarse), in my NA Miata... Thanks for your help.

MX-Brad

The blocks are the same.

cvx_20

The firing order and therefore the cams are different from the common Mustang 5.0 HO motors. Intakes are higher. Front dress (water pump, alternator) is different. So these differences can cause some fitment problems that will be different than the more commonly used 5.0 HO. But the blocks are the same

Mike

Eric3501

Thank you for the replies, and the heads up on the difference's, But if I switch to the 5.0 HO cam, and intake, to that of the mustang would not the Firing order change? Or am I headed the wrong direction on this line of thinking??? Thank you all for the help...

tbone heller

Moving 4 plug wires is all you have to do to change the firing order from standard to HO.

Eric3501

So just changing the firing order of those 4 cylinders. No changing anything in the Ecm to support the different firing order? Pardon my ignorance here but if I don't know something for sure, I ask questions....

tbone heller

Same as removing the HO cam & installing a Ford "alphabet" cam in a Mustang, except in reverse.
Or you could install an "alphabet" cam in your truck engine & change nothing.

Eric3501

Would not the stock camshaft in the truck 5.0 be an alphabet cam? And don't I want to stay away from them anyway? Thank you for all info. The car will be used for a D/D and an occasional trip around the cones...

Eric3501

So, On the rebuild I need to install a 5.0 HO cam before changing the firing order...Gotcha.

tbone heller

Why would you want to install a stock HO cam when there are many better options?

Eric3501

Well, With the car being 2300 lbs a lot of power isn't really necessary, and traction over a certain amount of horse power isn't getting to the ground anyway, just tire spin. I am going to do this on an extreme budget. I get Soc. Sec. Disability only so the less I have to put out the sooner I get it on the road.... It's a blast with the 1.8 in it now, but Would be a killer even with a mild build it.

Eric3501

Don't really know a lot about what works with what as for as power goes in the engine. I have minimal experience building engines, mostly maintaining what is already there, and did I mention this would be my first build... so please don't be too hard on me. I am reading the build threads on the site and any HELP you all can give me is greatly appreciated.

tbone heller

You will want the extra power, TRUST ME!

Eric3501

OK..so any suggestions on the cam? I am basically starting from a 1989 EFI 5.0 truck engine I'm pulling out of a truck. I basically have to rebuild it anyway. Don't know how many miles is on it. My Brother-in-law passed, and my sister gave it to me. #8 valve guides are pretty well shot and it recently started smoking. I am getting a pull out motor with a three year guaranty to put in the truck so I have this motor for the Miata...Everything else I have to source....Like Johnny Cash....One Piece at a Time...

Eric3501

Well, I got the replacement engine for the truck. It's a 1992 5.0 EFI from a F-150. Sheet that came with it says all 8 cylinders have 160 on the compression, and all the plugs are clean...A few have broke insulators, but were going to be replaced any way. I talked with the supplier and they said the truck it came from was from an insurance auction, but No one bothered writing the millage down. It needs some cleaning up, and some switching around of parts from one to the other at this point. Waiting on the first and payday before I can get much more done on this...Engine in truck will be torn down and rebuilt for my other project....5.0 powered Miata. But before that happens, this has to be dependable as well as the gathering of all the parts needed to do that...

MRM331

Because the newest stock 5.0 you get get now is 15 years old (2001 Explorer) very few people put bone stock ones in their builds. Since you are going to have to pull parts from different sources anyhow the actual source of the engine is less and less important. My actual block comes from a Lincoln MKVII. The intake and heads are from an Explorer, the alternator is from a Taurus, the starter is from that same Lincoln. Only the distributor, front brackets, AC compressor and the pulleys are actually from a Mustang and of those the most expensive, the compressor, was new anyhow.

Use the truck block, crank, rods and pistons. You're going to need to send a new oil an to MM if you go that route so that's not big deal. Get a set of cheap aftermarket heads or a set of GT40's. See if the truck intake will fit and if it does not sell it for a used Mustang intake which are dirt cheap. DO NOT use the truck cam: its designed to pull tree stumps out. Pick up a used Mustang one or even a new letter cam for under $300.

Good luck,
-Jason

Eric3501

Thank you MRM331 for the info. The motor in the truck, ('88-'89), is being replaced because it was cheeper to get a Pull-out than get the heads rebuilt around here, besides then I have a motor for the Miata, hahaha...
My plan for the one going into the Miata is to get either some GT40 heads or maybe some 351W heads...I have found conflicting info on this motor as far as the cam goes. Hoping it's the roller lifter, but can still get decent cams, ( I guess), for the flat tappet cams. I was hopping for something along the lines of a E303.
Yes, I plan on checking the bearings on the crank out and build the bottom end. Seeing's how the Odometer is mechanical and only 5 digit's, I have no idea how many miles is actually on the motor. My sister has no Idea, and it's showing 73,000 +or- a couple. Also water pump, oil pump, etc......
As far as the intake goes, it's gone...I am going with the carburetor version...I am not interested in playing with all the wiring head aches involved...so the intake will be sold...I was looking at the Edelbrock Performer intake with a performer series 600cfm IVS carburetor I am going to try and have all parts necessary on hand first as I am on a limited budget, so nothing outrages. To help with the expenses all parts removed from the Miata will also be sold...( i.e. the motor, trans, power platform, etc.).
And as I said before, I have to have the truck up and running before I start tearing into the Miata removing anything. I need my vehicle...