460 gas pig?
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460 gas pig?
Hi guys, I'm looking at a '92 F 350 crew cab 4x4 with a 460 4 speed overdrive auto trans. What should I expect with this motor? I've also got a 300 straight six that I was considering dropping in the truck with a few modifications. Is this wise? Does the 460 provide the necessarry horse power that the 300 can't?
Any advise would be helpful. Thanks, Trevor.
Any advise would be helpful. Thanks, Trevor.
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Joined: Mar 2001
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From: So Cal
My 94 F250 460 E4OD Supercab long bed 4x4 4.10 gets about 10-12 mpg unloaded with a mix of freeway and street driving. Towing an 8K travel trailer I usually get about 8-9mpg unless there are a lot of hills.
I think most of the mid 90s 460 trucks with same general equipment as mine get about the same mileage for the same driving conditions. The 350s might get a tad less due to a little more weight.
As far as whether the 300 has enough power, it all depends on what you want to do. If you tow a large trailer, then yes the 460 has plenty of power which the 300 doesn't. If you just want to tootle around town with no load, then maybe the 300 will keep you happy. I think it was an option in the light duty version of the 250 and maybe 350. The 300 is a good torque motor so I have read, while the 460 has plenty of both torque and hp, torque to get you rolling and hp to get you up to speed.
I think that I have read that the 300 in a 250 gets only a little better mileage than the 460. I think it is because of the weight and drive train drag. I might be wrong.
Unless the 460 was a total rag, I would consider keeping it in there. I don't think the 300 will give you enough economy to make up for the hassle of converting. I have never made this conversion so can't speak from experience.
Good Luck,
Jim Henderson
I think most of the mid 90s 460 trucks with same general equipment as mine get about the same mileage for the same driving conditions. The 350s might get a tad less due to a little more weight.
As far as whether the 300 has enough power, it all depends on what you want to do. If you tow a large trailer, then yes the 460 has plenty of power which the 300 doesn't. If you just want to tootle around town with no load, then maybe the 300 will keep you happy. I think it was an option in the light duty version of the 250 and maybe 350. The 300 is a good torque motor so I have read, while the 460 has plenty of both torque and hp, torque to get you rolling and hp to get you up to speed.
I think that I have read that the 300 in a 250 gets only a little better mileage than the 460. I think it is because of the weight and drive train drag. I might be wrong.
Unless the 460 was a total rag, I would consider keeping it in there. I don't think the 300 will give you enough economy to make up for the hassle of converting. I have never made this conversion so can't speak from experience.
Good Luck,
Jim Henderson
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From: Billings Montana
I was considering the exact same swap you're thinking of. I asked around and some people here told me that I would have to modify so much to make this work, I voted against it. Another thing to consider is generally, if you have to pass emissions tests, it's against the law to put an older engine in a newer truck. If the 300-6 is the same year as the truck, you're good to go, it'll have EFI. If the 300-6 is carbed and you throw it into the 92, it would raise a few eyebrows as a 92 with a 460 would be EFI.
I get about 10-12 mpg's as well in my 86 F-250HD. I have 4.10 gears and if your truck is geared that low as well, you could swap in 3.54 or 3.73 gears to give you some extra mileage. If you do a lot of towing, 4.10's are the ticket. All in all, a 460 is not going to give you very good mileage, but it will get any job done you need it to do.
I get about 10-12 mpg's as well in my 86 F-250HD. I have 4.10 gears and if your truck is geared that low as well, you could swap in 3.54 or 3.73 gears to give you some extra mileage. If you do a lot of towing, 4.10's are the ticket. All in all, a 460 is not going to give you very good mileage, but it will get any job done you need it to do.
Last edited by big hoss 29; Jan 19, 2005 at 02:10 AM.
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From: N. Gwinnett Co. Georgia
I am right in line with the 10-12 mpg in my '94. I am quite happy with the situation as I do haul a trailer every weekend. The 300 I-6 is a super little motor with a lot of torque. As long as it meets the engine year requirement you can make the change and let it be youe decision. I wouldn't due to my needs. If you were a little farther south I might make you an offer on the 460 though. Good luck.
Tex
Tex
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Build your 460 with an emphasis on low-RPM torque, which should also benefit you in better manifold vacuum and more efficient power production. Then swap in some taller (numerically lower) gears. The taller gear will have a slight effect on pulling power and off-the-line scoot, but the better power the engine produces should offset it. The end result will be about the same amount of "get up and go" but slightly better fuel economy.
Also - big, fat tires have a lot of weight and rolling resistance. In other words monster tires cost you fuel economy. A set of all-terrain, or even highway only, radials are much easier on the gas account.
Install some manual hub locks if your setup will allow it. Driveline parts weigh a lot, so unlocking the front driveline will help keep rotating mass to a minimum when you are not in 4wd. Every little bit helps!
Brad
Also - big, fat tires have a lot of weight and rolling resistance. In other words monster tires cost you fuel economy. A set of all-terrain, or even highway only, radials are much easier on the gas account.
Install some manual hub locks if your setup will allow it. Driveline parts weigh a lot, so unlocking the front driveline will help keep rotating mass to a minimum when you are not in 4wd. Every little bit helps!
Brad
Last edited by Brad Johnson; Jan 20, 2005 at 01:32 PM.
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Joined: Oct 2003
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From: New Jersey
Howdy... my 93 F350 longbed crewcab SRW hovers in the 12-14MPG range highway, and 9-10 local for the most part, with a 5.8L small block and a 5-sp ZF transmission.
I've been working on this project for a while, but I'm building a 500cid twin-turbo motor for it, and honestly, I expect the same mileage more or less, when driving gently. Like others have said, the 460 makes significantly more torque to begin with, and way down low in the RPM band, so you can change your differential ratio below what you have to compensate, and you'll have the same mileage.
While not a Ford, I built up a 1975 Dodge D200 extended cab (similar to F250) with a 451 twin turbo stroker, and it hummed nicely at 15mpg when I was gently cruising at 70ish, for this reason. EFI of course. A good blip of the throttle however spoiled potential gas mileage, but that's irrelevent to your point.
You can get decent mileage with a big-block for sure, many of us have done it.
If you want to invest a few dollars and a lot of time, you can replace your existing ECM (computer) with one from a Ford Lightning of similar year if you can find one, and use a program called Tweecer to adjust anything you like, tailoring your ECM data tables to match whatever cam, heads, etc that you choose on your new engine.
I've been working on this project for a while, but I'm building a 500cid twin-turbo motor for it, and honestly, I expect the same mileage more or less, when driving gently. Like others have said, the 460 makes significantly more torque to begin with, and way down low in the RPM band, so you can change your differential ratio below what you have to compensate, and you'll have the same mileage.
While not a Ford, I built up a 1975 Dodge D200 extended cab (similar to F250) with a 451 twin turbo stroker, and it hummed nicely at 15mpg when I was gently cruising at 70ish, for this reason. EFI of course. A good blip of the throttle however spoiled potential gas mileage, but that's irrelevent to your point.
You can get decent mileage with a big-block for sure, many of us have done it.
If you want to invest a few dollars and a lot of time, you can replace your existing ECM (computer) with one from a Ford Lightning of similar year if you can find one, and use a program called Tweecer to adjust anything you like, tailoring your ECM data tables to match whatever cam, heads, etc that you choose on your new engine.
