The secrets of the 351W V8

iamsparticus

Take your Rig to the Edge
Location
Ogden,Ut
So back in December of 2016 after my shop fire i sold my 1976 toyota drag truck and the amazing subaru Brat, due to both needed work and i could barely walk at the time let alone drive a stick shift. So i took the money from those and bought a 1991 f150 with a 5.8L or 351W motor in it, so i had something to drive and that i could haul rubble and tow things with. Naturally i wanted to modify it and get more efficiency and power out of it cause lets face it a early 90's 351W arent exactly a power house, but i knew from building other Windsor family motors that there was alot of shared parts but never got that deep into it cause i have mostly built 302 motors. So this led me to many hours of research on: parts sites, forums, and dedicated ford windsor fan built websites. Ive discovered that ford as built lots of amazing parts for these motors but just not on the same motor at the same time! So i thought id compile all this info for others to use and document my motor build as i go through it

Side note: this is only covering stock ford parts and the 1986 and up EFI small block windsor motors not earlier made carb models or the cleveland 351
We will start at the block and work our way up

blocks:
So the 289,302, and 351W all share similar blocks. All three engines have a 4 inch bore, 289 has 2.87 stroke, 302 has a 3 inch stroke and the 351W 3.5 icnch stoke. The two main differences between the 289, 302 and the 351 is the .5 inch taller block and much larger crank journal bearings. The 351W block has a .5 inch taller deck to allow the longer stroke, head bolt patterns are the same but distance between the heads is greater, not allowing lower intake manifolds to be interchangeable between the 289 and 302 to the 351W nor is the cranks

Heads:
The heads on the 289,302 and 351W are all interchangeable though not always desirable. The 351W came with small port and valve heads as well as lower compression due to larger combustion chambers in the heads. There was one 5.8L engine that had all the bells and whistles you could want but is so rare to find we will cover that in a later section. There are two stock heads that are very desirable to have on any windsor motor and they are the GT40 and GT40P heads.
GT40:came on 5.0 motors in for explorers from 1996 to 1997 or 1993 to 1995 Cobra mustangs and F-150 Lightings. The GT40 head flows amazing has longer and larger intake runners as well as bigger valves and ports. combustion chamber is 63 to 66cc's
GT40p: came on 97 and up 5.0 motors in the explorers and mountaineers and are different only in the smaller combustion chambers which results in raised compression, combustion chambers 59 to 61cc's and a slightly smaller exhaust valve 1.46 as opposed the GT40 1.54 exhaust valve. The spark plugs come out at a angle making the need for special headers or 90 degree spark plug wires to work
Both heads have stampings that say what they are toward the front under the valve cover as well as two lines on the front of the head for the GT40 and four lines on the front of the GT40P and a GTP stamped by the front sparkplug hole.

Cams:
So there isnt any extreme cams that were stock, if you want a cam for power the aftermarket has you covered for about a 100 bucks, but i will say this: After 1994 ford went from flat tappet cams and lifters to roller cam and lifters, Roller cams and lifters offer smoother and better control of valve lift as well as less horsepower to turn. cams are the same on 289,302 and 351w

Intake manifolds:
So intakes varied quite a bit on each motor as well as car to truck and the 289 was not produced in efi form as a windsor block so this section is just for the 302 and 351w. Truck intakes have longer runners for torque and car manifolds are lower with shorter runners as well as a single throttle bodies, trucks had two throttle bodies. For whatever reason the 351w intakes had smaller ports and diameter runners. The 302 intakes had much larger runners and ports. Due to the block height difference between the 302 and 351 the lower intake of the 302 will not bolt up to the 351w. There are very expensive intakes that you can buy for a 351W but there is a much cheaper option if you are willing to port your lower intake. The 302 upper intake from trucks will bolt to the 351W lower from trucks no problem and if you use the 302 upper as a template you can use that to trace the needed shape and size for porting and there is plenty of aluminium to do so. this will give you plenty of flow, if you need the truck set up. The car intakeis what you want use a combo of a mustang upper 302 and a early 90's grand marque lower from the 351W for best flow.

The special 351W
From 1993 to 1995 Ford put a special 5.8L v8 into the corba mustang and the f150 lighting. This version had the GT40 heads and the long runner larger port intakes. If you can find heads or intakes from these youd be golden but they tend to hard to find and expensive when you do. These motors made 30 extra horsepower over other 351W of the same time that where in trucks and cars.


I will be using all these upgrades on my 351W and will be documenting them on this thread as well as dyno numbers for each upgrade. Feel free to add to this or make any corrections if i have missed anything Enjoy :)
 
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iamsparticus

Take your Rig to the Edge
Location
Ogden,Ut
its been awhile since i posted this, work has kept me busy, i have started to collect the parts and plan a full engine rebuild as well as electric fans and water pump when i add the different heads and intakes
 

TurboMinivan

Still plays with cars
Location
Lehi, UT
The special 351W
From 1993 to 1995 Ford put a special 5.8L v8 into the corba mustang and the f150 lighting.

The 1993-1995 Mustang Cobra, plus the 1993-1994 Mustang Cobra R, all had 302 cubic inch displacement. The 1995 Cobra R was the only Mustang of this era to feature a 351 cubic inch engine; it was tuned to develop 300 HP, and production was a mere 250 examples (and Ford kept some of these for themselves). Like you said--good luck finding one of these OEM engines.

The 1991-1993 Lightning pickups all used a 351 engine. However, this truck version only made 240 HP and thus was not the same engine as found in the 1995 Cobra R.
 

iamsparticus

Take your Rig to the Edge
Location
Ogden,Ut
The 1993-1995 Mustang Cobra, plus the 1993-1994 Mustang Cobra R, all had 302 cubic inch displacement. The 1995 Cobra R was the only Mustang of this era to feature a 351 cubic inch engine; it was tuned to develop 300 HP, and production was a mere 250 examples (and Ford kept some of these for themselves). Like you said--good luck finding one of these OEM engines.

The 1991-1993 Lightning pickups all used a 351 engine. However, this truck version only made 240 HP and thus was not the same engine as found in the 1995 Cobra R.

thanks for the info looks like where i was going off had it wrong :)
 

iamsparticus

Take your Rig to the Edge
Location
Ogden,Ut
So i have made a little progress on this project, its been slow cause its been my daily driver, but i did shorty headers and got a upper 302 truck intake, and as soon as next month ill be tearing it the heads off and lower intake for upgrades as well as going to the later model roller cam set up and later model MAP sensor
 
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