I just got the bad news on my '77s 351m.. its days are numbered so im starting to try to figure out what my best option is.

I have a 360 out of '75 parts truck available, i can also rebuild my 351m. both seem to be underpowered. Long and short is id like some opinions on what the better motors are for someone on a budget rebuild.

The truck is an F250 that will be used primaraly for loads and towing. It is geared low. I'm not sure exact ratio but it runs at 4000 at 60mph on 33s, so good torque at higher rpm would be a good plus

Thanks for any help

 

460 and a gearvendor overdrive FTW

 

best money for your dollar is the 460. used and new performance parts are plentifull.

 

+1 on 460.

Good long blocks are plentiful on Craigslist. Do a little research first so you know how far you want to go with it. Its important to begin with the end in mind.

Spend some time in the 385 series big block part of this forum. Read a bunch of the stuff on there. Monsterbaby, who I think is a moderator in this section of the forums as well, knows about as much about these engines as anyone I have ever talked to.

Nothings cheap. My build that I am trying to do will probably cost me about $4000 with the new parts and machine work. Granted, I could do less and have a decent engine or I could do more and have a radical engine, but somewhere in between is what I want. Right now its just a greasy long block that I bought for $150 sitting on my garage floor.

I have no experience with the 351W, but I would think that could be a decent option as well with the right upgrades.

 

300 I6 with an Offenhauser intake and Holley 4BBL carb with a nice set of headers and Magnaflow exhaust. You want torque, that will give you torque.

 

2X on the 351W... Been looking into a 351W stroker motor. You can get these suckers to produce 700+ HP if you do it right, and the parts are plentiful!

I don't know much about the 460, but I know that it's a decent motor even as stock. The 351W is decent, but not meany for anything too heavy-duty (which is why I'm going to try out a 351 stroker motor).

Eventually I'll build myself a 408 stroker (long stroke) motor from a early 70's/ late 60's 351 so that I have gobbs of power and torque when I'm pulling more dentsides up hills and around bends.

My advice, is if you're willing to go into something for around the 3-5 grand range, get a stroker. It's got plenty of performance, and LOTS AND LOTS of write-ups and How-To's.

Look into a 351 my friend, it's been proven to get the job done!

 

do you really think that the 300 will provide more "torque at higher rpm" than a 351/360 (or larger 8cyl)
especially for the money (including mods)

 

I'd immagine that stroking the 351 could be one of the cheaper routes (lots of parts/kits available)

 

Not at higher RPM, but for towing/hauling you want the low end torque. Plus, the 300 will do it more consistently for many more miles.

 

I've looked into the 300 and 351 before. I'm sticking with the 351 because it's what I have...

I haven't found much difference between the 351 and 300, besides the fact that the 351 is more supported for this kind of application.

A 351 can have literally 10's of kits put into it (depending on what you want). You can go anywhere from 383/393 to 428.

I'd say that the 351 Windsor is better for this application because of the long line of parts that it has for it, but then again, I don't have much experience with the 300.

Although, when looking for parts, I don't ever see too many 300 items come up.

 

as the OP stated,
he's looknig for something that's gonna be in the RPM's a bit

I also found this on another forum (your post made me curious about the Offie intake's for my engine.

from what I've read,
these intakes never were really good for most v8 applications,
but people with I6's and Highway gearing really like them.

 

There's plenty of options, and opinions. All have their own strong points, and many have a few drawbacks.
A 460 would bolt to the current transmission behind the 351M, and would certainly offer more than enough power for towing. The drawback, you would need to source the motor mounts and towers, along with all accesory brackets.
The 360 out of a "parts truck" would most likely have all the motor mount towers and brackets needed to fit the engine into the chassis, but you will also have to swap the bellhousing (manual) or complete trans (auto). The 360 is a bit of a dog, but a 390 crank and rods will perk it right up.
rebuilding the 351M would seem like the easiest way to go, but this engine was also a major dog in factory form. There's plenty of ways to solve this, but it does add to the overall cost.
a 300 or 351W based engine, would also require motor mount towers and transmission attention, along with accesorry brackets. Getting good power out either is doable, but it's gonna cost you.
Out of all the options, the 351M/400 is the only way to go without needing to source brackets and frame mounts, along with transmission compatibility issues that go with anything else but a 429/460.
The additional items needed to complete a successful engine swap can really be a pain to locate without a complete donor truck to get them all from.
I haven't even discussed other little things like starters that may/may not change over, and radiators that might not work with a different engine family.

 

Offenhauser 6227C - Offenhauser C Series Intake Manifolds - Overview - SummitRacing.com

Says it improves power and torque up to 7000RPM.

These guys sell a ton of stuff for the 300:

Clifford Performance :: Make 6 = 8

And I love their tag line: 6=8.

Not trying to start a fight, but just trying to show the 300 can be a very potent engine for towing/hauling. The design of it lends itself to higher revs than most V8s due to it's seven main bearing design. Here's a little light reading for anyone interested in building a 6.

Building Up Six-Cylinder Engine - Mustang & Fords Magazine

 

^^Agreed RogueWulff. Everybody is so quick to suggest an engine swap. The best bang for the buck is to rebuild your 351m into a 400. While you're in it you can address all the factory problems/epa power killers and come out with a very reliable and torquey motor. Remember, the 400 had the longest stroke Ford ever made. The swap to a 460 has been covered who knows how many times and the consensus from people that have done it is that if you're final goal is 425hp or less, rebuilding the 351m/400 is cheaper than the swap and build of a 460. Past that the 460 is a lot less $/hp.

Besides that, something isn't right if you're turning 4k @ 60mph. It would take a rear gear of 6.20!! with a C6 and 6.55!! with a NP435/T18 to be turning those kinds of numbers. Gear Ratio Calculator
I doubt it's geared that low, transmission not shifting into final gear? A 3.73-4.10 rear gear (depending on man. or auto trans) and a tranny not shifting to its final drive will equal..about 4k @ 60.

 

Sleepy brings up a very valid point about the RPM. Something isn't right if it is turning 4K @ 60 MPH.
Heck, with that kind of RPM, the MPG would be so poor, no one could afford to drive it much....


As for the 300 I6 and all the power adders available, they're out there, if you're willing to pay the price. But no matter what you add to a 300, it's not gonna hit 7,000 RPM and live to talk about, without some major work to the lower end. Simply put, it wasn't designed to exceed ~3500-4000 RPM. In fact, the head flows so poorly in stock form, that it won't go much higher under a load. Even with all of clifford's mega $$$$ stuff bolted on it.
This engine was designed for low end torque, and it does this job quite well.
Which brings me my other point. A 400 shares the same low end torque traits of the 300, in large part due to the 4 x 4 bore/stroke both engines have. Converting a 351M into a 400 is the cheapest way to make a major improvement in available torque. Addressing the previously mentioned factory shortcomings adds more to the equation, without adding a lot to the cost.
351M/400 were very under built at the factory, in order to keep the EPA happy. Looking at info easily found in the 335 series section can help you make the right choice for what *you* want/need the engine to do.