the 7.5 is in a whole different class of motor.. the 460 is just crazy power.. it is going to suck up some gas of course but ford 7.5 was a really impressive motor.. not saying the 5.8's are bad.. just saying comparing the two is like putting a ranger up against a 3/4 ton.. and seeing which can tow more

but there aftermarket support isnt as good as the 351w right? cant you mod a 351w to where its right there with a 460, like new heads, headers, cam, exhaust, cai?

its really not hard to find aftermarket cams/headers.. most of the 460's you see are custom exhaust not bolt on not sure about heads.. if you are ever wanting to buy parts and can't find them summit racing has almost everything you could need.. yes you can beef up a 351 to almost a 460's stock output.. but then again you can do the same to a 302 to get way more than a 351.. and you could do the same to a 460 to make the 351 seem like a 4 banger.. if you are looking for a cheap motor to have fun with i would say the 302 because it is so common you can find some cheap bolt on stuff.. if you are looking to make an off road rig i would go for the 460 or a 390bb i personally like the 390's.. they were common in lots of 70s to early 80s.. their smaller twin 360 was a POS which got worse mileage and obviously worse stock power.. and almost every single one of them had exhaust mani leaks.. freaking metal on metal no gasket.. and a fail design at that..

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if you want to build a 460 some good heads are going to run you about 1k+ a good cam isn't going to be too pricey really.. exhaust i would just run true duals into maybe some 40's.. never really cared for hi flow cats and performance exhaust.. not exactly sure what the cost of headers would be for the 460.. i know the 360/390 are dirt cheap.. don't know too much on the 427/460 bb but from bone stock spending no more then 2k in parts you would have a pretty well built beast..
what are you wanting this big of a motor for? off road rig or a towing rig? truck 2wd or 4wd? or are you just looking to see what people say about them?

My trucks a 89 F250 351w 2wd. Im very happy with the 5.8 and im just gonna build it up with heads, headers, cam, and cai. My 1st thing in mind to do before i start engine modding it is lifting it. I found a 6 inch skyjacker lift for it and then im gonna throw some 35s BFG all terrains. Its mainly gonna be for show and my liking, but everynow and then i do hit the mud/ offroad trails. But in the future im gonna look into getting a 460

That vintage 5.8 is a mere shadow of what it's capable of, if you're happy now you would be absolutely floored by what a few simple upgrades(cam and exhaust) do for this motor, and completely stunned with what happens when you put proper heads and intake on it. You will have to work within the limits of the stock EFI system however so you're not going to be able to see all it's potential but the right combination of parts can add 50-60 points to both the horsepower and torque curves.

ya mines bone stock except for a cheap glasspack lol, but even in stock form you KNOW there is power under the hood, and im just lookin forward to modifying it.

for the 351w if you do heads, cams, exhuast and intake mods you might as well go ahead and get an aftermarket efi controller to handle whatever you do to it, about $100-200 and with that you can easily acheive 350hp and 420-450 ft-lbs and get better mpg than you have now and with a lift on it, if you get a 460 its all the same mods really as you would to a 351, but personally id go for the efi version, harder in many ways but output is worth it, ive seen many 460s run 500hp and 600 lb-ft, but a simple stroker to it can put it at 600hp and 750lb-ft with the proper extras

Depending on the year of the 460 though... Stock vs stock they have the same numbers as a 351w. I have a 96' efi 351w and I was considering a 79' 460 swap but my hp/torq are nearly better then it. Then I was looking into an efi 460 (which are hard to come by because I want the California model for MAF) but it would cost more to just swap the 460 in then it would cost to rebuild the 351w.

There were no 390's in the 80's, 1976 was the last year. Praising the 390 yet calling the 360 a "POS" makes no sense since those are the same engines except for the stroke length because of different piston rods and crankshaft. The 360 is a reliable workhorse that won't let you down.

As far as mpg I'm getting about 15 with 1/3 city 2/3 highway driving. Unloaded with a lot of hills sea level to 800 feet. Never done an all highway run but with a little less stop and go I get 16. Bone stock other than 2 inch duals from o2 sensor back with glasspacks

Uh no
 

You do know that many versions of the 302 put out more HP and TQ that the 351 at lower RPM right? So...the 351 is actually better at higher rpms, but still wont rotate faster than the 302 due to rotational force. So, imo, the 302 wins that category.

How about a 451 Cleveland?