Thinking about going to a smaller motor

[66camperspecial]

I love the power the 460 has but its thirst for fuel is a little more then I can handle so I am going to be looking for a 351-W or 302 to drop in it,I want to be able to drive it longer then just locally so,the big block will have to go. I picked up a 95 F150 set up for towing so its going to handle the towing and hauling so the 66 can be a toy to just cruise. 9 or 10 miles to the gallon just is not enough so I am going to be looking for something light to put the 460 in to do some playing at the track on weekends,I am going to leave the 460 in for the rest of this year and I hope to find a decent small block over the summer and install it next winter as I have too much to do this year.

[66camperspecial]

Just after I put the automatic column in now I am thinking about going back to a manual trans if I go with a smaller motor,I did keep all the clutch parts and 4 speed column.

[ICEMAN6166]

sometimes, especially climbing the big hills i wish i had an fe instead of the y-block.
would likely not change mileage much and i just care about getting to where im going.

[LM14]

The problem with changing engines for better mileage is, while you might pick up a couple miles per gallon if the swap is done correctly, you may never drive the vehicle long enough to re-coup the costs associated with the engine swap.

Also, people tend to think in terms of smaller engine = better mileage. Not always true. It can actually go the other way if you work the smaller engine where the bigger engine was loafing along.

You are usually better off working with what you have. Good tune, good intake and carb, good exhaust and ignition, proper gear ratio and OD tranny. There are a lot of ways to improve mileage that are a lot cheaper than swapping engines. Creating a complete package that is properly tuned will probably gain you as much as, or more than, a swap will.

SPark

[66camperspecial]

I was hoping the 460 would have done a little better but plan on tinkering with it a little before I decide to pull it,I had a 65 country squire that had a 390 that would get 16 on the highway and since the 460 has more torque would have done the same.

[jamesdfo]

So, what is the 460? Is is a stock motor out of a donor vehicle, or a rebuilt to stock specs, or has some mods?

Stock smogger 460's were pretty underwhelming.
A rebuilt 460 with a mild RV type cam & a holley, headers & a good dual exhaust is a completely different engine than a smogger

[banjopicker66]

With my 460 and C6 automatic transmission, I got close to 15 MPG on the freeway at 65 - 70 MPH. Empty or towing, not much difference. But I wanted the truck to be able to tow a car hauler, so I wanted more power than a 302 can put out, but I do sacrifice mileage around town.

It is basically a mild build for towing and mileage. It is an '80s block with '86 carburetted heads. Edelbrock 600 CFM 4 bbl carb on a Performer intake (not the RPM), pre-'72 timing gear set, and '80s serpentine belt and pulleys. I also installed what is colloquially known as an "RV" cam. Like the intake, it is best suited for a balance of power and mileage at lower RPMs, up to a maximum of about 4,000, as opposed to high RPM usage. (The "Performer RPM" intake is designed to work best at higher RPMs, so it would be a poor match to use with an "RV" cam.)
No headers, just the stock (aftermarket) exhaust manifolds and dual exhaust. My research indicated that Ford put enough research into the exhaust manifolds that headers would provide only marginal improvement, if any.
The engine started life as a fuel injected one in a 1989 (or so) F-350 camper that was rotted from salt. I put carburetted heads with the latest engineering design on that block; they have E6 "casting" numbers. These heads are supposed to be the most free-flowing with larger valves. Supposedly, these were the ones Edelbrock used as the patten for their performance aluminum heads.
Essentially, it is built as an early '70s 460. I do not know the compression ratio, or the types of pistons, or if it could be rated as a muscle car engine, but it has plenty of reserve power when I hit the secondaries.

All this in front of a 3.25 rear end ratio. A 3.00 or 2.75 would increase freeway mileage, but would really hammer performance and mileage in stop and go traffic.

Around town, mileage was terrible, so I wouldn't recommend a 460 if your daily travel is stop and go.

With the 600 CFM carb, there is plenty of reserve power. No need whatsoever for anything bigger, it just eats the fuel.

[66camperspecial]

The 460 came out of a 77 F350 that was a Jasper rebuild,I think D1 block with D3 heads with a Edelbrock performer intake and maybe a Edelbrock 750 carb. Do not know if its a RV or stock cam or the timing chain set but it did run much better then a untouched 77 460 that I had in another truck so I presume it could have straight up timing,it has a stock late 70s duraspark distributor and 2.75 gears and dual exhaust with manifolds. I would like to tweek the 460 and see if I can get a little better mileage before pulling.

[chris401]

The 460 came out of a 77 F350 that was a Jasper rebuild,I think D1 block with D3 heads with a Edelbrock performer intake and maybe a Edelbrock 750 carb. Do not know if its a RV or stock cam or the timing chain set but it did run much better then a untouched 77 460 that I had in another truck so I presume it could have straight up timing,it has a stock late 70s duraspark distributor and 2.75 gears and dual exhaust with manifolds. I would like to tweek the 460 and see if I can get a little better mileage before pulling.

http://www.network54.com/Forum/74182/thread/1254637079
Look at WerbyFord's comment. He posted some good info on the 385 family in other post as well. His post tend to be practical for the everyday driver. I have been told the 400M with a dual plane intake makes good torque, but if your taking any kind of poll I vote FE.

[ICEMAN6166]

but if your taking any kind of poll I vote FE.

make it 2 votes

400s make good boat anchors IMO.
replaced a few with 429s over the years.

going small block take a 351W.

rather have a 300 6 than a 302, unless its a car

all that said i have been mostly happy with the y block in my truck

[66camperspecial]

I still have all the parts to put a FE back in including the bellhousing and flywheel and do have a toploader 4 speed looking to go in something.

[LM14]

What do you do with the truck? Mostly in town stop and go slow speed driving or mostly highway? Highway at 55 or highway at 70? Highway/City at 50/50 of each? How will it be used the most?

Daily use 5 or 6 days a week or just for fun on nice days?

The intended use would make a huge difference in the "best" combination of parts.

SPark

[66camperspecial]

I am going to use it just for fun now that I bought the 95 F150 to do all the work but I want to be able to drive it to swapmeets and shows that are over 100 miles away and be able to afford the gas.

[LM14]

Go with a good tune and put in a 3.25 gear. If you are running 60, it will help a lot and not completely kill it around town. If you are running 70 or so, overdrive would be your friend. Go with a 3.50 gear and overdrive and you get the best of both worlds.

SPark