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Discussion Starter #1 (Edited)
My project is an 86 F250, with a 4spd and stock 460, about 105K miles. My dad bought it new, so I'm fixing it up, and having some fun with it. There is some sentimental value attached to it, but I also don't want to invest a pile, so I'm doing some junkyard building - it is just a truck, and the primary purpose is to haul wood and plow snow. It'll be a 0-5500 type engine.

I've sourced an 89 ranch truck, it's a little beat up, but has only 75K on it, with a 5 spd, and 460.

My plan is to swap the 5spd and block from the 89 into the 86, then use the heads/intake/exhaust manifolds from the 86.

There are two main benefits I expect to get from the 89 block, from my research (please to correct me if this isn't true):
1. The piston dish in the 87-92 block is only 7cc, while the stock 86 pistons were 22cc. With stock 86 heads this should bump my compression to about 9:1, give or take with my rough math.
2. Ford switched back to a straight up timing set in 87, so I don't have to worry about that

Will I run into any problems putting this combo together - head gaskets, water flow, oiling, etc... ??

Should I switch to the serpentine setup (if they had that in 89), or stick with v-belts?

I'll be looking into other performance questions eventually - such as minor work to be done to the heads, cam swap, intake, carb, etc... but right now I just want to know if my above assumptions are true and this will work.
 

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My project is an 86 F250, with a 4spd and stock 460, about 105K miles. My dad bought it new, so I'm fixing it up, and having some fun with it. There is some sentimental value attached to it, but I also don't want to invest a pile, so I'm doing some junkyard building - it is just a truck, and the primary purpose is to haul wood and plow snow. It'll be a 0-5500 type engine.

I've sourced an 89 ranch truck, it's a little beat up, but has only 75K on it, with a 5 spd, and 460.

My plan is to swap the 5spd and block from the 89 into the 86, then use the heads/intake/exhaust manifolds from the 86.

There are two main benefits I expect to get from the 89 block, from my research (please to correct me if this isn't true):
1. The piston dish in the 87-92 block is only 7cc, while the stock 86 pistons were 22cc. With stock 86 heads this should bump my compression to about 9:1, give or take with my rough math.
2. Ford switched back to a straight up timing set in 87, so I don't have to worry about that

Will I run into any problems putting this combo together - head gaskets, water flow, oiling, etc... ??

Should I switch to the serpentine setup (if they had that in 89), or stick with v-belts?

I'll be looking into other performance questions eventually - such as minor work to be done to the heads, cam swap, intake, carb, etc... but right now I just want to know if my above assumptions are true and this will work.
The swap will work as you have described.

Ford never made a true serpentine setup for the 460. I would stick with v-belts.

Recurving the distributor will help wake it up, as will a free flowing dual exhaust system.

If you want to upgrade from the stock cast iron intake manifold use a regular Edelbrock Performer intake and a 750 cfm vacuum secondary carb.
 

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Discussion Starter #3 (Edited)
Thanks for the info

I was thinking about giving a go a porting, and removing/reshaping the thermactor bump. If the heads need freshened up, maybe I'll just take them to the machine shop and have them do it. I'm not sure how much they'd charge for doing that.

The regular eddie intake was what I was thinking, but I was considering of going to the holley truck avenger 670... too small?

Any suggestion on a cam?
 

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The carb top end on the early EFI short block will yield about 8.5 to 1 static c/r.
the 6 cc dished pistons have a short Compression height leaving them about .030" in the hole at TDC.

Short cam timing with a focus on low RPM usable torque along with a properly curved distributor are in order.

The BBF returned to straight up cam timing with the EFI engines. Replace the timing set with an OEM style replacement set when you change the cam.

Heads will have to have the guides topped and p/c seals added. Better springs are a good idea.

The performer intake is a good fit. Restrict or block heat depending on location and time of year primary use.

A good performance valve job, back cutting the intake AND exhaust valves and bowl work is worth the effort.

Avoid the avenger series carbs. A 600 holley is more than adequate. Our 400 hp EFI engine uses less than that on the dyno.


SJ
used 2b RHP



:D
 

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670 is fine but I am not a fan of the Truck Avenger carbs. If budget is a concern look at the Summit brand carbs. Quick Fuel also makes some nice entry level carbs now.

As far as the cam goes I am no expert but I wouldn't go much bigger than something like 204/214.
 

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Discussion Starter #6
The carb top end on the early EFI short block will yield about 8.5 to 1 static c/r.
the 6 cc dished pistons have a short Compression height leaving them about .030" in the hole at TDC.
Ah, well, maybe it isn't that sweet of a swap then. I thought I'd stumbled upon an easy cheap bump in compression. A stock 86 should be about 8:1 correct? I may have to consider just putting the effort into an actual rebuild on the 86 block... I'd like to get to 9-9.5:1. So can I assume that compression height of the 86 pistons leaves them more like .020 in the hole?

Short cam timing with a focus on low RPM usable torque along with a properly curved distributor are in order.

The BBF returned to straight up cam timing with the EFI engines. Replace the timing set with an OEM style replacement set when you change the cam.

Heads will have to have the guides topped and p/c seals added. Better springs are a good idea.

The performer intake is a good fit. Restrict or block heat depending on location and time of year primary use.

A good performance valve job, back cutting the intake AND exhaust valves and bowl work is worth the effort.

Avoid the avenger series carbs. A 600 holley is more than adequate. Our 400 hp EFI engine uses less than that on the dyno.
The other carb I had in mind for a cost effective solution was the street demon 625. You can get them factory refurbished from holley for stupid cheap, but maybe there is a reason for that. Sounds like they are mostly bolt on and go though with simple adjustments. I'll look into quick fuel as well.

SJ
used 2b RHP



:D
Awesome information, thank you.
 

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Discussion Starter #7
670 is fine but I am not a fan of the Truck Avenger carbs. If budget is a concern look at the Summit brand carbs. Quick Fuel also makes some nice entry level carbs now.

As far as the cam goes I am no expert but I wouldn't go much bigger than something like 204/214.
Thanks, I'll keep shopping for carbs. I didn't realize summit carried their own brand. Anything that lines up better with the stock fuel lines and throttle linkage could persuade.

I may do the carb and intake on the 86 right away before I do anything else. This thing runs terrible and barely idles... never has run right. I suppose the stock carb could be made to work, but my Dad has fought this carb since he bought the truck new and never got it right so he's really looking forward to running it over with the loader when I replace it.
 

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Discussion Starter #8
The carb top end on the early EFI short block will yield about 8.5 to 1 static c/r.
the 6 cc dished pistons have a short Compression height leaving them about .030" in the hole at TDC.
Okay, so I'm double checking here, I had found the the piston specs on this thread:
https://www.460ford.com/forum/37-engine-tech/128570-stock-piston-specs.html

1968-1972 460 pistons stock dish, -12 cc, 1.76 compression height
1973-1986 460 pistons stock dish, -22cc, 1.75 compression height
1987-1992 460 EFI pistons stock dish, -7 cc 1.76 compression height
1993-1997 460 EFI pistons stock dish, -15cc, 1.77 compression height
This is showing that the 87-92 actually has a higher compression height than the 86, with a -7cc dish, so, if I put the 86 heads on an 89 shortblock, wouldn't that aid in even more compression? Does anyone know what the actual deck clearance of each short block is? Am I looking at these numbers incorrectly?
 

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Okay, so I'm double checking here, I had found the the piston specs on this thread:
https://www.460ford.com/forum/37-engine-tech/128570-stock-piston-specs.html



This is showing that the 87-92 actually has a higher compression height than the 86, with a -7cc dish, so, if I put the 86 heads on an 89 shortblock, wouldn't that aid in even more compression? Does anyone know what the actual deck clearance of each short block is? Am I looking at these numbers incorrectly?

See post 4



SJ
 
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