5.0 parts/build questions

1990_LX

1990_LX

Clubhouse Moderator
#1
#1
So I got another 5.0 but this time I got a roller one. It's a 86 motor out of a Grand Marquise and I already pulled off all of the EFI crap and put my intake and carb on for the time being. The motor has no accessories other then an old water pump, has 90k and low oil pressure. I'm thinking new rings, bearings, and a new oil pump will resolve that? I flipped it over on the stand and pulled the pan off and there was no major sludge and no metal shavings, pieces, chunks, ect so that's good. So a few questions here...

1)I have 2 timing covers, one on the EFI motor and one that was on the carbed motor, the only difference is the hole where the mechanical fuel pump lever goes through it is punched out on the carbed one and not the the other so that leads me up to the question about fuel delivery. I hope to put is in my 90 when it's all done so how should I go about getting fuel? Can I put an inline regulator and then just directly connect the line coming from the pump to the mechanical fuel pump or right to the carb? Would it be best to find a take from a non EFI can and re run the lines?

2)How should I go for ignition? Points or electronic? Advantages/disadvantages to either?

3)Any good rebuild kits? I was looking at some at Sumit but I'm not really sure if I have to replace all of the bearing or not as some kits come with just cam and some come with main ect.

4)Would it be worth it to have my block hot tanked? Cost?


I'm sure I have more questions but I'm too tired to think right now. This is not going to be done in like a week, I'm just trying to nail down a parts list and get some prices going to I know what to expect and so I can slowly stock up on some parts and then bang it out in a couple of weeks once I have what I need. Thanks in advance for any help!:)
 
Gingerbreadman

Gingerbreadman

Well-Known Member
#3
#3
so ur removingg efi and goin to a carb set up? ,if it has low oil pressur and ur looking to rebuild probly be in ur best interest to hot tank and rebuild.o maby just a new short block,.how do you know it has low oil pressure? did u see the motor run first?
my opinion electronic is better always for tunin purposes,,,,
 
1990_LX

1990_LX

Clubhouse Moderator
#4
#4
Quick281 told me so, and I got it for free so I don't suppose he would be in a position to lie about it....I was plaing on a rebuild so would that mean I need to to ALL the bearings? I can't afford a new short block so I'm working with what I got. Also, yes I took off all of the EFI shit and threw my Performer manifold and carb on it.
 
BMad

BMad

Well-Known Member
#5
#5
Personally, I would hot tank it, hone, rings and have the shop put cam bearings in it. Inspect the crank. If it had low oil pressure the crank may have some wear. As for Points, you can go with a petronics type system. The kit system drops in the distributor where the points would go. It's a easy swap and they work well. My father has been using this system in his 69 convertible. Or if you have some extra cash, you can go with a Mallory type unilight distributor. I'm partial to this system because I have been running the unilight in my 67 coupe, and then transferred it to my 83 fox. Points are ok, they just wear out, and float at higher RPM's 4500+ They can act like a unreliable rev limiter. As for the fuel pump, there is a bolt-on lobe on the front of the cam that drives the fuel pump on non EFI engines. If your late model engine doesn't have this lobe, you might have to go with a electric fuel pump and regulator. Normally, if you have low oil pressure, the main and cam bearings are normally the cause. Replacing these will eliminate the problem. replacing the oil pump is standerd practice when you have the engine torn down. I would also replace the timing chain.
 
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BMad

BMad

Well-Known Member
#6
#6
As for prices, I would call a few machine shops in your area, prices very drastically from shop to shop. The few shops that I have been talking to don't give out price lists like they used to. They explained to me that they stopped this practice because of the newer engines have been blowing their prices out of the water. They compared porting a cylinder head on a 5.0 would be 1/4 the price of porting the head on a import engine.
 
Jays04mach1

Jays04mach1

Well-Known Member
#7
#7
It's too bad you couldn't have the engine running to get a reading with a handheld oil pressure gauge. 90k isn't a terrible amount of miles. I'm almost betting you'll be fine running the shortblock you have. I'm interested in your EFI setup. Let me know what you want. As for a fuel setup, You could get a pre 86 sending unit and run a mechanical pump. Running an EFI pump with a regulator could work, but your looking at restricting a 40-45 psi pump down to 6 psi! You could get a pump from a carbed 86 with an electric pump. The 86 GT's used this. And your problems will be solved.
 
1990_LX

1990_LX

Clubhouse Moderator
#10
#10
BMad said:
Personally, I would hot tank it, hone, rings and have the shop put cam bearings in it. Inspect the crank. If it had low oil pressure the crank may have some wear. As for Points, you can go with a petronics type system. The kit system drops in the distributor where the points would go. It's a easy swap and they work well. My father has been using this system in his 69 convertible. Or if you have some extra cash, you can go with a Mallory type unilight distributor. I'm partial to this system because I have been running the unilight in my 67 coupe, and then transferred it to my 83 fox. Points are ok, they just wear out, and float at higher RPM's 4500+ They can act like a unreliable rev limiter. As for the fuel pump, there is a bolt-on lobe on the front of the cam that drives the fuel pump on non EFI engines. If your late model engine doesn't have this lobe, you might have to go with a electric fuel pump and regulator. Normally, if you have low oil pressure, the main and cam bearings are normally the cause. Replacing these will eliminate the problem. replacing the oil pump is standerd practice when you have the engine torn down. I would also replace the timing chain.
Click to expand...
Yes I just looked and mine has that rounded bracket on the cam sprocket so I'll use my other timing cover and run a mechanical pump.

Thanks for the help thus far you guys, I'm heading back out to the garage and I'm sure I'll have more questions when I come back in!:D
 
Gingerbreadman

Gingerbreadman

Well-Known Member
#13
#13
the 86 mustang is speed density efi ,yes,,dont know if u need one but i ran a carb set up for stock 85 motor and i still ahve the pump,its like a 5-9 psi pump,doesnt look the best but i know it works and u can have it,its an inline pump,i have no use for it,,as for short block rebuild like he said before new bearings should fix that and u might as well get the pumps and other stuff while its out
 
dsblk93gt

dsblk93gt

5.0 Moderator
#18
#18
The Crown Vic uses smaller injectors, 14lbers, and a different intake setup than a Mustang.

I'd get at least some TRW forged pistons if on a budget.....
 
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