1991 Ford F-150 5.0 ?'s

[texastechbronco]

Is the block in a 1991 F-150 5.0 the same roller block as the H.O. mustangs? Also, can any of the injection parts (MAF, misc. sensors, etc.) be used on a mustang 5.0 setup?
Thanks

 

[Broncobowsher]

The block should be the same.
The truck doesn't have a MAF, so it won't work
Harness is different, truck is batch fired, car is sequential
EGO, ACT, EGT should interchange
Distributor gear must be changed if going from a flat tappet cam to a roller or roller to flat
Truck manifolds might work
ECM won't (unless you keep the harness and keep it a truck engine)
Heads should be the same. The factory trick for '87 was to use the truck heads.

 

[Brake Guy]

I do not believe so, this is all from memory when I rebuilt the motor in my '89 a few years ago (my memory sucks)

The fireing order is the standard 302, the H.O. motors share the 351w firing order. They are not roller motors. they are Speed density (not MAF). the intake is way to big to fit under the hood of a bronco without some major hood mods.

 

[66horse]

I would agree with the previous post but I would think a 91 would be a roller block.

 

[Brake Guy]

I would agree with the previous post but I would think a 91 would be a roller block.

that I was fuzzy on, thanks for the info.

 

[adambronco74]

I just looked at a 1991 302 from a F-150 and it wasn't a roller rocker.

 

[66horse]

I just looked at a 1991 302 from a F-150 and it wasn't a roller rocker.

Well there ya go.

 

[Broncobowsher]

Ford was making roller blocks and using a flat tappet cam. From what I remember all 302 blocks after '85 were roller. Wasn't cost effective to have 2 part#s and castings when you can run flat in a roller block. Starting in '85 all service (warranty and replacement) blocks are roller compatable. (does not apply to the 351)

That came from the ford motersports catalog may years ago.

You probably have a roller block that never had the roller lifters installed

 

[TexasBronco]

Tech!!! yay! I am just a senior in High School but have already been accepted to Tech...I should start classes sometime next fall. My brother who lives in Lubbock said he has seen quite a few Broncos around town... which one is yours?

 

[66horse]

Now fellas, you know the only school you should even consider going to in Texas is UT.

 

[Broncobowsher]

Well there ya go.

Roller Lifter started in the '85 302 block. started in '94 in the 351 block
Roller Rocker was only used on a few cobra engines. usually just an aftermarket item.

The 2 parts a both valvetrain parts, but that is as close as the are to each other. There is a pushrod seperating them and they do 2 very different jobs.

 

[Brake Guy]

Roller Lifter started in the '85 302 block. started in '94 in the 351 block
Roller Rocker was only used on a few cobra engines. usually just an aftermarket item.

The 2 parts a both valvetrain parts, but that is as close as the are to each other. There is a pushrod seperating them and they do 2 very different jobs.

Right, but the question was only about roller blocks.

my understanding is that the only thing that makes a roller block a roller block is that the two bosses in the valley are drilled and tapped to hold the retaining plate. I also believe that non roller blocks can be turned into roller blocks by drilling and tapping holes in the valley.

 

[Broncobowsher]

There are a few other differences.
The lifter bores are taller to accomidate the rollers. If you retrofit an old (non-roller) block to a roller cam, the lifters will be lifting the aligning plates off the valley floor. Retrofit kits use a shorter base circle cam to overcome this problem. The choices of small base circle retrofit cams is small and poor for a bronco last I checked.

 

[JFX]

On the late '93 Lightnings if the block has an F4TE stamped above the starter, then it is a roller ready block.

I'm not sure if they used the same type of labeling on the 302's.

A few Lightning Guys have switched to a roller cam, (a Mustang GT cam works),lifters,dogbones and longer push rods are required.


Good Luck,

JFX