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FoxBody Engine build

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4
0
Exp. Type
Drag Strip
Exp. Level
Under 3 Years
North Carolina
Got a 91 lx 4banger looking to drop in a 5.0 and have a 5.0 ho just dont know what it came out of.. whats the best overhaul kit and options
 

PatientZero

@restless_performance
825
865
Exp. Type
Autocross
Exp. Level
10-20 Years
Kansas City, Missouri
We really need a lot more info. What is your intended use for the car? Are you wanting a stock rebuild or more power? Stock or aftermarket heads? What is your budget? What transmission?

I would suggest finding a local engine builder and consult with them. Based on your location you should have plenty of options.
 
4
0
Exp. Type
Drag Strip
Exp. Level
Under 3 Years
North Carolina
Street and strip and more power if i read right stock heads for the ho are 351w heads right? Im a diesel mechanic and rebuild motors and have built a few gas burners but dont know the 5.0 HO to its entirety... and buget is obviously low lol im a diesel mechanic... lmao
 

PatientZero

@restless_performance
825
865
Exp. Type
Autocross
Exp. Level
10-20 Years
Kansas City, Missouri
If you are assembling it yourself I'd assume you will at least need machine work done. It's really all going to depend on your budget. Obviously the tighter your budget, the more compromises will have to be made. The cheapest thing to do would be to have the block honed .005" and throw in new rings and bearings. If you wanted to spend a little more you could bore the block .030" and bump the compression up a little with a better piston. If you wanted to go deeper down the rabbit hole you can buy a complete rotating assembly but 302 blocks like to split in half between 4-500hp. If you were going to spend that much money I'd rather put it into a 351 block. As for the heads, you could do a simple valve job and new guides, you could go to bigger valves with some port work, or go to an aftermarket head.

Personally I would bore the block .030" with a better rod and piston and put some good aluminum heads on it and have fun. 300whp wouldn't be too difficult.
 
4
0
Exp. Type
Drag Strip
Exp. Level
Under 3 Years
North Carolina
Ok thanks whats a good brand for the pistons and an overhaul kit in your experience? I was alsothinking about a carb conversion so i dont have to try to find a comp and harness what are you thoughts there?
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
2,009
441
Southeast
Jay:

You should give PZ more information on your desired HP goal & budget allowance.

You can think about the type of piston in relationship to your HP goals.

Some types of pistons are Cast, Hypereutectic or Forged.
 

PatientZero

@restless_performance
825
865
Exp. Type
Autocross
Exp. Level
10-20 Years
Kansas City, Missouri
Contrary to to what anyone may tell you, there is nothing wrong with a well tuned carburetor. Well tuned being emphasized. That means putting it on the dyno and trying different jet sizes to make it run right. As cheap as wideband O2 sensors are now it's so easy it's almost cheating. With that said, once you buy a quality carb and jets and dyno time you won't be far off from a Holley Sniper system or just keep the stock 5.0 EFI.

If you never plan to go over 350hp and never plan to use any power adders you could go with a quality hypereutectic piston but then you're limiting yourself later. Just pay the money once and put a forged piston in.
Between 9-10:1 compression will make a nice street motor for pump gas.
 

302 Hi Pro

Boss 302 - Racing Legend to Modern Muscle Car
2,009
441
Southeast
Perhaps Jay should disassemble what he has to see what he’s working with.

IMO that would be a good start.
 
4
0
Exp. Type
Drag Strip
Exp. Level
Under 3 Years
North Carolina
Well the thing is i have no "allowance " in just tring to compromise overall work with outcome... As i said i am a deisal mechanic now and i am hovering over a 200+ degree motor for 12 hrs a day. I built a regular 5.0 in my pickup and its pushing 300 just trying to see what are the best fits and options for this H0
 
6,361
8,183
here's a good parts source...
also, for some reason Ford built those engines with monster bottom ends, they can take huge amounts of boost, they are one of my favorite engines.


and if you are really, really bored and a decent machinist, this would be a great project....these guys always have issues with machining the timing gears though, I would think by now, someone would have the pattern set.



also...


Buddy Ingersall's Pinto


with that engine, you have the whole world at your disposal.... and a lot less nose weight than a V8
 
Last edited:
6,361
8,183
but..if you insist on the 5.0 here's a build for you

that's a VERY dependable build that is streetable, and reliable..if you wanted you could add some GT heads and it would go even faster, but you'd have to watch your compression ratio on the street a bit. That is my go to cam, for 302s.

 

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