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Howdy, I have my beautiful baby my 78 Bronco with a 351M and a c6 Tranny. My engine is the original, never been rebuilt, everything's old and breakin down. I think I'm just about done with the whole, something break, go fix it, wait a day, something else breaks kinda deal. I want to swap in an engine that I know isn't gonna leave me stranded. I was thinking a 460 with a T-18? I really want a standard transmission. If y'all could provide some insight so I can start putting together the things I need, I'd very much appreciate it. To begin with, as I understand the 351M and the 385 series use the same motor mounts, or am I mistaken? If so how hard is it gonna be to make it sit there? Also what are fair prices for the 460 and tranny to go with it? What else am I going to need? Anything you wanna add it I am open and ready to listen. If you even wanna suggest a different engine, I'll listen. I chose the 460 because its a powerful (torque wise anyways) and extremely reliable engine, and that's what I'm looking for. Something I can drive to pick up some milk, then go wheel in on the beach and get back home with out destroying something. Any and all input is heloful !
 

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From my own experience transmisson wise it is alot easier to swap in a manual with a donor truck. As that is what i am doing now. Although it is a little more involved as i am doing a body swap as well. Youll need the master/booster for a manual, pedal assembly, linkage, z bar set up, i believe the trans mounts are in different spots and different driveshafts. If you have a buddy with a manual trans in his truck see if you can borrow his for the weekend so you can compare. If you are going to swap in a manual trans go for the np435. Stronger with a lower first gear than the t18. I have a t18 but thats because thats what the donor truck came with and i got a good price on the whole set up. Check out my build thread if your interested.

Engine wise 460 would be a good choice in my opinion. Throw a 4bbl, headers, and a mild cam and youll be rockin :rockon
If you wanted to get really involved you could throw dov3 heads on it and work it up good. Depends how involved you wanna get and how deep your pockets are.
 

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Discussion Starter #3
Pockets are shallow lol.. And what if I'm just sticking with the c6?
 

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If sticking with just the c6 the 460 will bolt right up no problem. My buddy is running a built 460 c6 combo on 52in tractor tires running 4.10 gears.
Youll need motor mounts, rad hoses, probly a rad and electric fans would be nice and a starter. Not sure what else as i am still running my 351.
Now depending on the condition of your c6 will depend how long it holds up. A c6 will no doubt hold up to a 460 but if you have a hurting c6 with 200,000 on it and you go from 150hp to 350hp its a whole new beast. Just keep that in mind. Not trying to discourage you from the swap just remember what you are running with and how much life it has left.
 

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Oh no I appreciate it! Honest to god i dunno how many miles are on it. It was a barn find and first thing I did was put a working cluster in, fixed the rat eaten wires to it. I figure I'll swap it in and drive it till it breaks
 

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Yeah if you go 460 and keep the c6 maybe put a mild shift kit/valve body in and you should be good. My highboy has a 460/c6 combo and it puts up with the 460 perfectly. As far as what you'd need for the 460 swap fender exit headers would probably be the easiest route for headers if you go that route and other wise it's like he said, mounts, nice beefy radiator, and as for building one up just throw on a nice 4 barrel carb and an aftermarket aluminum intake and you should be good. But like he said different heads and a cam would be cool too. Just depends on what you're looking to do. Also if you don't want to have the c6 rebuilt by a shop they're honestly really easy to rebuild and there's plenty of videos/instructions on the Internet to figure out how to do it. When I did mine the rebuild kit was I think $125 and if you switch valve bodies depending on which one they're around 2-300. But still better than paying 800 plus for a shop to do it
 

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Yea. A shift kit would be a good idea. I put one in my other bronco with an AOD. It was easy. Just remember what bolt went where when taking the valve body out. Take the bolts out clockwise starting from the oitside and working in and lay the bolts out in a line as you take them out. When reinstalling start in and work your way out goin counter clockwise. The biggest thing is to keep the valve body clean!!!! Also buy a filter kit while your doing the shift kit if you do it. B&M make great products. That's who made mine.

As for swapping it in and driving till it blows id be doing the same thing myself especially since money is tight. I would definatley do a intake and 4bbl before I put it in tho. But that's mostly because I can't leave anything alone. You could always do that later.
 

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Exhaust manifolds; some pass car units fit, some do not clear the frame rails. Best bet is truck manifolds off a 73-79 460 equipped truck.

The 351m distributor will work in the 460, so no messing with ignition wiring.

Cheapest motor mounts I know about, are solid steel units, from Trans Dapt, at 75 bucks a set.

If you do any wheeling, change over to a rear sump oil pump and pan. The front sump pan is WAY too close to the front differential.

If the 460 you get is hooked to a C6, use that torque convertor.

For a radiator, use AT LEAST a super cool unit. I ran a 400/ac radiator for years, with only a few minor overheating issues.

Your 351/C6 starter will work fine with a 460. Plan on a bigger battery.
 

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From someone who has done this to a '78....Here are some tips:

The 460 swap is the least expensive, most logical, and biggest "bang for your buck" mod for power and torque. Aside from engine mounts and exhaust, it is a bolt in swap.

The factory 199? 460 stater is a PMGR. I highly recommend it if you have some wiring skill.

351M-400 engine mounts do not fit the 460. Conversion mounts are ~$100 from summit or JBG.

EFI engines came with a nice serpentine belt system, some of these came from the factory with saginaw PS pumps. The brackets fit a 460 / 78-79. The complete setup can be had in the bone yard for $100.

Be prepared to find the weak links of your drivetrain with that added torque. The 1310 Cv will likely be tyne first thing to break. I am using a 1350 Cv from a late model super duty. So far no issues.

Truck / Van manifolds work great. The L&L ¾ length headers also fit very well. Both of these will be trouble free. Do not use gaskets on the manifold, use Remflex gaskets with headers.

1995+ 460 efi used a one piece oil pan gasket with a steel center. You can buy a kit from ford racing with the truck oil pan, sump, gasket, and dipstick for about $170. This is the setup to have for no leaks and it is stupid cheap. Find some 460 oil pan rails and convert the 4 "corner bolts to ¼-20 to make it fit nicely.

I use a "vatozone" CU545 radiator. The fit is OK, it cools fine, and the price is right. Every year or two it springs a leak....but by then its time to change the coolant anyway.
 

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i built m 351 to a 400..i run my c-6 with it, making good power, yes i rebuilt the engine, put aussie heads and a comp roller, edelbrock inake, flow tech headers, x-pipe with magna flow mufflers, approx 400 hp and torgue works great, plus the m blocks are lighter tan a 460 by about 100 lbs.
 

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I have to agree with outlawbob. I swapped my 351M for a 400, punched .040 over with a 4bbl Edelbrock. I,m not quite running 400hp, but I eat all of the newer trucks alive. 400 is a direct bolt in swap, and any motor you buy (unless it's a crate) will need/should be rebuilt first anyhow.
 

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I agree with the comments above. Best thing I ever did to my 78 was a 460 (.030) swap. I used a 71 lincoln 460, it gas good heads on it and it had good numbers right out of the factory.
Go with a rear sump oil pan weather you're wheeling with it or not.
Get a radiator that is designed for a 460, no 351M/400M rad is big enough. I HAD a super cooling rad on my old 351M and you can physically see the difference in thickness between it and the 460 unit.
Also, I recommend you keep it simple. Stay with the C6, have it rebuilt and slap it back in. Don't complicate the project by taking on too much. I did that and next thing you know 5 years have gone by and it's still sitting in the garage in pieces because you haven't gotten around to finishing it. Too many other, more important family things come up all the time.
There is literally hundreds of articles on 460's and swapping a 460/429 into 78/79 broncos. Do your research. Go to 460ford.com and learn all you can about this awesome powerplant. You can get so much power and reliability out of that motor. Starting in 78 they went with a different flywheel (internally balanced) so be careful not to mix and match too much. Also, very important, study up on the different models of heads, there are some really undesirable heads out there and there are some great ones.
Plus, a 460 can be bored out to.080, try that with a chevy 454… not.
Good luck, we're all counting on you!
 

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X2

Drop that 460 in and show the M-block fans what they are used to seeing....tailights.
 

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As stated above, you WILL find the weak spots even with a stock 460. I don't know if you've noticed, but no truck that originally came with a 460 came with a 9 inch rearend, there might be a reason for that, don't get me wrong though, the nine is tough as nails, just not that tough. I almost did the swap myself but then after some research found out the 400m actually builds more low end torque, sure it doesn't stand a chance at the high end, but I use mine to tow and crawl, so In my opinion the 400 was my best option since I spend most my time in the low end.

It depends on what you want it for.
Blowing the doors off ricers, go 460
If your hauling a john deere around, Go 400M

But that heavy duty radiator never hurt anyone.
 

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[QUOTE ck 460. I don't know if you've noticed, but no truck that originally came with a 460 came with a 9 inch rearend, th/QUOTE]bullshit....plenty of 2 wheel drive trucks (and cars) came with a 9" with the 429/460.driven sensibly, shouldn't be a problem.:shrug
 

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As stated above, you WILL find the weak spots even with a stock 460. I don't know if you've noticed, but no truck that originally came with a 460 came with a 9 inch rearend, there might be a reason for that, don't get me wrong though, the nine is tough as nails, just not that tough. I almost did the swap myself but then after some research found out the 400m actually builds more low end torque, sure it doesn't stand a chance at the high end, but I use mine to tow and crawl, so In my opinion the 400 was my best option since I spend most my time in the low end.

It depends on what you want it for.
Blowing the doors off ricers, go 460
If your hauling a john deere around, Go 400M

But that heavy duty radiator never hurt anyone.
I think you have it backwards. The only arena the 400 csn compete with a 460 (if they are built similarly) is the top end.
I've learned a lot about what the 400 can do if built properly. The problem is reliability. If you try to make it keep up with a 460 it loses reliability. It has oiling issues and is a smog era motor whereas the 460 was built back in the late 60's.
However, the 400 weighs much less than a 460. I've heard by as much as 145 pounds. That's a lot but you just have so many more options with a 460. You can change the crank and rods and make it a high reving 429 if you want speed. Plus you can put a number of different head and piston configurations on it to do anything you want and that's before you start talking about stroker kits.

I do like the 400 though, it is an impressive plant if built correctly.
 

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Yeah, pros and cons to both. I did not consider a 460 mainly due to the weight. Maybe I should have? But I'm happy with my 410 efi build which I built more for reliability/efficiency than for torque or horsepower. Only issue I have is a tappet that makes noise when cold. I'll have to pull a head one of these days . . . :toothless
 

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[QUOTE ck 460. I don't know if you've noticed, but no truck that originally came with a 460 came with a 9 inch rearend, th/QUOTE]bullshit....plenty of 2 wheel drive trucks (and cars) came with a 9" with the 429/460.driven sensibly, shouldn't be a problem.:shrug
Sure, Lincolns and such had a nine behind a bigblock, but none of them or 2wd trucks have low range, and thats where the breakage begins. I should have specified 4x4's.
 

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Howdy, I have my beautiful baby my 78 Bronco with a 351M and a c6 Tranny. My engine is the original, never been rebuilt, everything's old and breakin down. I think I'm just about done with the whole, something break, go fix it, wait a day, something else breaks kinda deal. I want to swap in an engine that I know isn't gonna leave me stranded. I was thinking a 460 with a T-18? I really want a standard transmission. If y'all could provide some insight so I can start putting together the things I need, I'd very much appreciate it. To begin with, as I understand the 351M and the 385 series use the same motor mounts, or am I mistaken? If so how hard is it gonna be to make it sit there? Also what are fair prices for the 460 and tranny to go with it? What else am I going to need? Anything you wanna add it I am open and ready to listen. If you even wanna suggest a different engine, I'll listen. I chose the 460 because its a powerful (torque wise anyways) and extremely reliable engine, and that's what I'm looking for. Something I can drive to pick up some milk, then go wheel in on the beach and get back home with out destroying something. Any and all input is heloful !
So original 351m is nearing 40 years and never been rebuilt and is unreliable?

:rofl:
 
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