eBronc's 351W 
eBronc's 351W
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I came across mine in an '85 F150 Supercab that had a stuck hood. Not being
able to easily open the hood had kept the engine dry and prevented parts from
being scrounged off of it. I just used an old axle I found lying around to pry
the hood open, and there it was - greasy, grimy, dirty..but it was a Windsor,
and I knew it was a 351 from the wide intake manifold and the emissions sticker
on the radiator support. $150 and it was mine..after I went and rented a trailer
to haul it back home with. I doused it with Castrol Super Clean (wear gloves
when you use this stuff, by the way), then hosed it down in a car wash before I
backed the trailer into the garage to unload it.
The 302 block that was included (but not installed)
when I got the Bronco was toast- 4 pistons had holes in them, and there was so
much rust I couldn't budge the crank. I really wanted a 351W for the truck,
anyway, so I called around and searched most of the salvage yards around town
until I found what I was looking for - a complete, carbed 351W that was still
pretty well protected from the elements.
Not having an engine hoist, I had to wrestle 600 lbs of wet engine back to the rear of the trailer so I could bolt my engine stand to the back of the block, then used my floor jack to raise the tounge of the trailer slightly so the wheels of the stand rested on the floor. With the full weight of the engine on the stand, I thought for sure it would snap like a twig..but it held. (It did bend and bounce a lot, though.) I didn't like the looks of that at all, so I fabricated a diagonal brace from the lower leg to the upright out of 1" square tubing and 1/8" flat strap. With this installed, the engine was MUCH more stable, and I wasted no time removing parts.
The A/C compressor, alternator, P/S pump, water pump, intake, and exhaust manifolds all came off pretty easy. After removing all the plugs, I sprayed plenty of WD-40 into the cylinders and tried to turn the crank by using a 1/2" ratchet on the center balancer bolt..but no dice. I just threaded the flywheel bolts back into the crank about halfway, then used a short crowbar leveraged off them to finally break it free. After a little oil in the cylinders, it spun over pretty easy, so I knew the crank and bearings were probably OK and the rings weren't broken.
The first mistake I made was when I turned the block over so I could remove the oil pan..I had removed the drain plug earlier, but nothing had come out, so I forgot about it. When I started to turn the block over, 5 quarts of black, chunky goo came pouring out. DOH. (At least it wasn't rusty water.) I also noticed the rubber ring on the harmonic balancer was coming out from between the inner and outer rings, so I'll need to replace that.
Two of the bolts that go through the water pump and the timing cover into the block broke off at the head when I tried to remove them, but I was able to slide the pump and cover off. Getting the broken bolts out of the block wasn't quite so easy. I tried penetrant, heating the block, and Vise Grips. I even tried welding a nut to the bolt shanks so I could get some torque on them - they just broke again. I finally cut them flush with block, used a punch to dimple the center of the bolt, then drilled through with a small bit. I stepped up to a larger bit and tried an easy-out, but the bolt STILL wouldn't budge, and I was afraid of breaking off the easy-out. I just kept stepping up the drill bit sizes until I reached one just slightly smaller than the threads, then used a tap that matched the threads to clean them out. It took a few hours, but they're good as new now.
I ended up having to drive the lifters and the cam out, but the timing chain was so loose it nearly fell off the sprockets. When I removed the main caps, the stench from the old oil trapped in the bottom of the bolt holes nearly gagged me. I used a punch to knock all the old freeze plugs INTO the block, then turned them sideways and pulled them out with Channelocks. The smaller plugs for the cam oil galleries I removed by drilling a 1/8" hole into, then screwed in a self-tapping sheetmetal screw, which I grabbed with ViseGrips and levered out with a big old screwdriver. The threaded Allen-head plugs at the back of the block, the lower sides, and the filter oil passage behind the cam gear came out once I heated the block, soaked with penetrating fluid, and used an Allen socket adapter on my 1/2" drive ratchet. The new brass freeze plug set I bought didn't include the 1/2" dia plug for the oil galley crossover in the lifter valley in the block, was short 2 of the NPT Allen-head screw-in plugs, and didn't include the (4) 1-1/2" plugs for the ends of the cylinder heads, so beware if you order a set thinking it's going to have everything you need. It probably won't.
Once I had everything apart, it was cleaning time. Everything but the block went into my parts washer, and I spent plenty of time with an assortment of brushes scrubbing all the sludge and carbon off. I broke one of the old piston rings removing it, so I used it as a scraper to clean the ring lands on all the pistons. A 10" length of old coat hanger worked great for cleaning out the oil passage in the pushrods, and a tiny wire brush in a Dremel cleaned up all the old rod, head, and main cap bolt threads. I chased all the threaded holes in the block with taps (lots of crud in the last 1/2" or so of all the holes!) and used a small tapered stone in a die grinder to remove casting flash and burrs from inside the block, and smooth all the oil drainback passages and water ports. 2 gallons of Castrol Super Clean, lots of scrubbing with nylon and brass brushes, (rifle and pistol bore brushes and rods work GREAT on the oil galleries - .270 caliber for the small ones, .45 for the larger ones), and a final rinsing with a pressure washer got most of the grease and sludge out of the block.
The stock 351W heads had those stupid "emissions humps" in the exhaust ports, along with a TON of carbon buildup on the backside of the intake valves. I disassembled and cleaned the bare heads, then cleaned the old (but good) valves by clamping the stems between rubber jaw inserts in my bench vise, and using a small wire brush in a Dremel to clean the stubborn carbon off.
I grabbed my safety glasses, gloves, earplugs, dust mask and die grinder and got busy porting the heads. The first things to go were the humps in the exhaust ports, then I concentrated on smoothing all the sharp edges, casting flash, and ridges in the valve bowl area and port runners. The intake ports hardly needed any work at all-just a little tapering of the valve guide bosses and some work on the transistion of the short-side radius to the bowl area. I was careful NOT to increase the size of the port too much, just to remove any obstruction to easy airflow I could find. I used a set of intake gaskets to scribe around the intake ports, then opened them up to the scribed line and blended the ports about 1 1/2" back into the heads. I left the finish of the intakes slightly rough, but smoothed the exhaust ports as well as I could to keep them free of carbon buildup in the future. Here's a link to a great DIY cylinder head porting site I used. I also used the die grinder to port match the intake manifold and reshape the water jacket ports from the "L" shape they came cast as to the rectangular shape that matched the water ports in the cylinder heads.
I don't plan on building a race motor, and I can't imagine driving this thing down the Interstate very far, so I thought I'd try to get away without having ANY machine work done...(I'm cheap, remember?) - BUT, after measuring the cylinder bores for taper, I found that they were just too far gone to run as they were, so I had the machine shop bore them .030" over and honed for moly rings. The main cap mounting surfaces were all square, though, and both decks showed less than .001" warpage across their entire length. Both cylinder heads had about .006" warpage right around the middle of the heads, so I had them cut .010" to true them up and raise the compression ratio just a bit. I also had the machinists Magnaflux the block and both heads for cracks, and had a valve job done. Supposedly they hot-tanked everything after all the machine work, but if they did, I couldn't really tell - there was still crud in some corners of the inside of the block, the oil drainback holes, and the oil gallerys alongside the cam journals which I had to remove with an old toothbrush, bore brushes, and some degreaser. I was NOT impressed by the $60 "Hot Tank". I ordered a PAW rebuild kit with new .030" pistons, moly rings, bearings, gaskets, high volume oil pump, and a slightly hotter cam and new lifters. I also invested $16 in an ARP chromoly oil pump driveshaft, just as insurance against failure of the stock shaft.
After painting the heads and installing the brass freeze plugs, I made sure the valve guides were clean by running some cotton gun bore swabs soaked with WD-40 through them, then gave them a shot of clean motor oil and assembled the valves, seals, springs, retainers and keepers. (I goofed and had half of them done before I remembered the seals..DOH.)
First part to go back into the block was the new camshaft. I made sure the cam bearings were clean, then coated them and the cam with assembly lube and carefully slipped into place. That was easy. (Kinda slimy, but easy.) The cam thrust plate went on after lubing it well, and I made sure to use the 2 special half-head-height bolts to bolt it to the block. If you try to use just any old 7/16" head bolt, the cam gear will hit them when it's installed. Trust me on this.
The crank was usable after I polished the journals with 400-grit cloth, made sure the oil holes were all clean, and ran a tap into the flywheel threads and the balancer threads in the snout. After verifying the new main bearings were the right size, I installed the top halves into the block and laid the crank in (carefully!), then used Platiguage to measure oil clearances. Everything was within spec, so I removed the crank, wiped it down again, then slathered assembly lube (slime) over all the bearings and crank journals, laid it back in place, and torqued the mains down to 100 ft-lbs. It spun freely, with no slop and the thrust clearance was ok, too.
I used the feeler guage method to check piston - bore clearance on every hole, then VERY carefully spread the rings (tape your thumbs if you do this the hard way.. like I did) just enough to slip them over the pistons and into the correct grooves, paying very careful attention to the dots on the top of the rings. I used paper shop towels soaked in laquer thinner to get the cylinder bores as clean as I could, then blew them dry w/air and wiped them down with a different shop towel soaked in oil. The piston/connecting rod assemblies were pre-lubed by dipping them upside down into a coffee can half-filled with oil, then slowly inserted into thier respective bores, making sure the arrows on the pistons pointed towards the front, and the stamped cylinder numbers on the connecting rod caps were toward the outside of the cylinder banks. (Make sure you've got the conrod bearings installed before you do this...) After sliming the journals and bearings, I torqued everything down, checked side clearances, and verified deck height.
I ran into a major snag when I trial-fit the oil pump pickup tube and the "351W swap" oil pan to the block..it didn't fit. Oh, the pickup fit the pump and the block, and the pan fit the block, but the pan hit the tube in several places. Oops. After doing a little checking, it turns out that I should have bought the matching pickup when I bought the pan off eBay-but I didn't realize that at the time. I still had the original, '84 F150 351W pan that came off the motor in the first place, so I knew it would fit...it was just incredibly grungy, since I had never bothered cleaning it. Using it, though, was still cheaper than buying a new oil pickup, and after test-fitting both pans to the Bronco chassis, it actually looks as if the F150 pan will fit a little better - about an inch more clearance between the front sump and the front axle pumpkin.
After a few hours in the parts washer, stripping off the old paint, pounding out a dent or two (my neighbors loved that part), I treated the pan with naval jelly to neutralize the surface rust, cleaned it again, then sprayed it with a few coats of paint. Good as new. Well, close, anyway.
The timing chain was installed next - the crank gear just slips over the snout, line the chain up on the sprockets, and install the cam gear and fuel pump cam so that the dots on the upper and lower gears line up. I installed an adjustable, double-roller set, so I used the 4 degrees advanced keyway on the crank gear for more low-end torque. After slipping the oil slinger over the crank, I bolted on the timing cover, using the balancer to center the oil seal. Pay attention here, too - one of the bolts that secure the timing cover to the block (2nd up from the bottom left) is just slightly shorter than the others, so don't mix them up (like I did.) The balancer slips over the crank snout and needs a little persuasion (I used a brass punch and LIGHTLY tapped the center flange) to go back far enough so that you can use the big center bolt and washer to pull it on the rest of the way. I used a little anti-seize between the crank and balancer to make it easier to install (and possible to remove in the future).
eBay supplied a new aluminum reverse roatation water pump ($20), a used but perfect aluminum Edelbrock Performer intake ($55), new thermostat housing ($6), used 5.0 Mustang shortie headers ($16, w/the 351W and the 2" body lift they fit fine), Q-jet carb ($15), a used (but good) 3G 130 amp alternator from a junkard police-spec 3.8L Taurus, '89 Lincoln power steering pump and bracket, and the stock Duraspark distributor (triggering an MSD Offroad box) rounds things out. Check out the "Tech" page for more details on the serpentine belt swap. Total estimated cost? $500. (I've blown past that already.) Total estimated torque and horsepower? 350 ft-lbs, 300+hp. Like I said, plenty of power.