what parts did ford add to the 351 to make it a HO? was it anything more than a 4bbl?

 

E7TE heads, which come stock on all post 87 351W's

 

Different cam, intake and carb.

Chris

 

I got hold of a dead one and tore it down. I found nothing of interest. The heads are about the same as those on a 5.0 but I prefer the early 70's "big valve" 351W heads. Incidentally, 1987 was the last year for carbureted 351W HO engines. 88 and up are EFi engines and not denoted "HO".
All the rest of the engine is pretty much the same as any other 351W as far as I could tell. I don't know about the cam, but considering that a good percentage of "HO's" are to found under the head of 3/4 ton work vans I doubt they are of much interest.
A Mustang 5.0 HO erngine is rather more interesting, but near as I can the 351W HO basically seems to denote just what you said, a 4BBL carb.
On a similar note, I also tore down an early 80's police car engine. Nothing at all of interest there either. The only difference between it and any other 351 was the addition of an oil cooler adapter that fits under the oil filter.
I'd like to get my hands on a 94-6 Lightning engine and see what they are, but doubt that will ever happen.

 

The big thing about the 351HO was the power output, 205 hp/315 ft/lb IIRC(may be 215/305) The intake, 4bbl, and cam made a large improvement over the 2bbl version(163 HP IIRC. Really not that special, but, it got the 17" 460 air cleaner with some fancy lettering on it... LOL

 

I drove my brother's '85 F-150 with 351HO this past week. It did pretty decent on gas, about 14 mpg, but I wasn't real impressed with its pulling power--acceration isn't bad if it's unloaded, but after hooking up a trailer, I thought I might need to get out and push. Rear end is a 3.00 if I remember right, maybe that hurt it, but the trailer weighs about 1300 lbs which didn't seem like it should drag it down that much.

 

I've been SOMEWHAT impressed by the one in the '86 that I inherited from my late uncle last year. It runs pretty strong, and I think with headers/true duals and a slightly more aggressive cam it would be a screamer. I intend to prove that theory soon. Hopefully in the spring...

 

thats interesting guys, i just found out that our 86 e350 has the 351 HO in it. it must have been a pretty good engine in order to make my dad think it was a big block. it never had any trouble pulling trailers, even one rated at 16000 if i remember right. but i was thinking about pulling the engine out, using the good parts to be me an econo race car for the local dirt circle.

anyone know what the holley on it would flow? 650 would be my guess

oh and it does have a pretty sweet air cleaner, although its lettering is all gone.

 

The 351HO had a lopey cam in it.. Put duals on it and you will hear it.. It's the same engine that they put the EFI system on. Mine goes one step further, it's 351EFIHD, it;s got a huge throttle body, and bigger injectors. It sounds like a stock car when you stand on it.

 

Maybe we need to put a lower rear end in brother's '85. It runs pretty good on the highway, just can't pull much starting out. Or maybe I just didn't shove my foot far enough into it.

 

That's one change I made in mine early on... I put a Quadrajet on it. I know, flog me if you must, but I still think they are the best carb you can get for street use. Mileage went up, throttle response off the line improved greatly, and it passed the local smog test (something the Holley wouldn't do to save its' a$$). As for that throttle response, I've opened the secondaries less than ten times since the swap. It'll pull so hard at 1/4 to 1/3 throttle that I rarely need to. It'll also squall a tire on dry pavement at the drop of a hat and breaks free a little TOO easy in the wet. This with a 3.00 gear and power-hungry C6. I've got 90% of the stuff to EFI it, but wrecked it in the spring and have hardly driven it since. It's dependable too. After three months of sitting last weekend it fired right up and worked flawlessly all day moving a friend's furniture. He even commented that it would fly... and when I popped the hood he was impressed by the air cleaner as well. Especially the 5.8 H.O. part. Easy to trip people out who are used to less than 2 liters.

 

My brother's '85 did okay getting the trailer out of the driveway, just when we needed to pull on the highway and accelerate that you could feel the extra weight. We'd pulled a car on a towbar with it a few days before, 10-25 MPH, and on that it pulled as well as my F-250. I've been thinking about kitting the carb anyway, any time it sits more than a couple hours or so you have to prime it to get it started, so I know something's not working right now.

 

ours has 4.10's, which is probably why it never had to try to get up and go with a trailer on. but keep in mind that without an overdrive, your not gonna get anywhere very fast!

and i dont blame you at all for using a quadrajet. its a good carb.

 

The 351 Lightning motor was a 351w with the GT40/Cobra induction peices. Ford Motorsport had come up with a tig welded tubular upper intake manifold, and improved cast iron cylinder heads designated GT40 for the Mustang 5.0. They had a GT40 5.0 crate engine with the GT40 heads, B303 cam, and the GT40 tubular intake rated at 285HP. This crate engine became the Cobra motor except the Cobra upper intake was a cast version of the GT40 upper intake and the cam was basically a derivative of the 5.0L Mustang roller lifter cam, rather than the non pollution friendly B303. The rockers were 1.7 ratio roller rockers. The Cobra motor was rated by Ford at only 235 HP in 93, but my brother and I transplanted one into a 86 Mustang. We had it on a chassis dyno were we got 265 HP at the wheels, so the fly wheel horse power had to be at least 285.

The lighning 351 motor used the GT40 5.0 head and intake peices, and the mustang roller cam on the 351w. The lightning actually got the tubular version of the upper intake, but it has the throttle body on the drivers side, instead of pass side. They say the tubular intake will flow enough air to support 450 HP. My nephew just bought a Lightning with the GT40 351. We were surprized to find it to be speed density rather than mass air. The Truck has 4.10 gears, so with 364 lb-ft and 310HP (factory rated power), it gets it.

When Ford first started desiginating 302's and 351w "HO"'s in the early 80's they were really nothing special. The big difference was mainly the 4bl carb and the "marine" cam. They used a 351w marine engine cam, with similar specs to the old 351C 4bl cam. This only mildly boosted performance from the typically tepid early 80's smog motor levels. But a little better is better than nothing.

The 5.0L HO became somthing more than just a standard pollution controled V8, with a hotter cam and a Holley, in 1985. This engine used a better head (E5AE), forged flatops, high volume oil pump, double roller timing chain (timed straight up instead of retarded 4*), and the brand new for 85, HO roller lifter cam, underneath the the 4V induction. The EFI 87-93 5.0 liter HO's use basically the same short block, as the 85 5.0 liter HO, but with E7 heads instead of E5's. The E7TE's didn't come along until 87, although the E5AE 302 heads are very similar. The 86 5.0 liter HO roller motor differs in several aspects from both the 85 and 87-95 5.0L HO roller motors.

 

I need to make a couple of corrections concerning my comments on the lighting 351, in the above post. I talked to my nephew, and he has recieved data from SVT about his truck. The Lightning 351 uses a flat tappet cam, not a roller cam like in the Mustang 5.0L HO. They only call it the "high tourqe cam". The "official" power levels are 240 HP, and 340 ft-lbs, but those figures are known to be deliberately under rated. In the old Ford Motorsport catalogs the Lighting 351 is rated at 310 HP, with the stock short block using GT40 heads and intake.