RPM HP / Torque
2000 203 / 532
2500 252 / 529
3000 301 / 527
3500 344 / 517
4000 377 / 495
4500 390 / 455
5000 380 / 399
5500 353 / 337

My torque with the Cam listed by Kubota above peaks at 2000 rpms. I dont have a stroker engine but IMHO torque for pulling a trailer doesnt get much better than peaking at 2000rpm. Thats getting into the realm of Diesel performance. I have 38.5" tires and 4.56 gears and I get 8-10mpg. It could be much better with higher gears lighter tires and smaller foot

 

you would be surprised....500 rwhp is cheap and easy with a 12v compared to a gas engine




I really liked that cam i was talking about....gobs of low end torque and a decent mid high range...

I just put on edelbrock heads and a custom solid lunati cam in, hopefully ill be breaking her in tomorrow
232/238 @.050" .541/.569 114lsa

torque peak at 3500....553 ft lbs, but it shows over 530 ft lbs from 2-4500

 

just remember one thing if you are on a budget and gas prices are 3.50 a gallon in some areas for premium bigger isn't always better. if you are going to drive it every day and don't mind putting $100.00 to $200.00 a week in the tank ( ouch! ) than go for it. otherwise after the fun wears off of it after a few months than your really going to be tired of sinking that much gas in it ( all ) the time.. just go with a nice 460 bored .060 over and a good cam and it should be a very good motor..

 

for a 514 you could get anywhere from about 14 mpg to 4 gpm, depending on how you build it, how you drive it, and what you put it in. i think monsterbaby said his race truck gets about 4 gallons per mile, and thats a 528 running race gas. dont know if he got his 572 done yet, but im sure thatll get about the same if not a little worse, though i dont know how much worse it could get

 

My goal will to build an engine that gets the best mileage I can, (I get 10 MPG empty/5-7MPG towing) so my goal would be to get more low end torque & better mileage. I know that can be done. I tow at 65 MPH 2400 RPM, I only go over that RPM if I have to go into second to get up an incline. But with better low end torque I might be able to not have to go into second as much, or if I do part throttle instead of full.

 

well... how much money are you willing to part with? if possible id say go to a roller cam- better power, and less friction for better mileage- as long as you dont go crazy with the duration (duration kills mileage and low end power)

 

I don't know where they are getting the information on higher compression or higher lift cams giving you bad gas mileage. My experience says different. I am sure there is a limit to both, anything over 10.5 to 1 requires special gas making it unattractive for a daily driver. A drag race cam on the street would yield bad gas mileage because most of the time you are driving beneath the power band.
I have an 1986 F-250 running a 429, 10.0-1 compression, 5500 rpm hydraulic flat tappet cam, 33" tires. I got 14mpg on the highway with the back loaded with about 800lbs, now city gas mpg is crap. I also have a 1970 mustang with a 400hp 302 10.5 to 1 with a 6800 rpm solid roller cam and it got 20mpg on the highway.
A guesstimation for the torque required to pull a 10,000lb load down a lever highway would be in the 150 to 200ftlb range. To get the optimal mpg you will most likely want a built EOD transmission. Get your Highway (65mph) rpms around 2200 might be able to go 2000 with a 514 (514 9.5-1 6300rpm produces over 500ftlbs at 2000rpm) but I don't think I would go under that, if you do it will put a lot of mechanical stress on the motor. On the other hand unloaded you could run around 1800rpms.
Suggestions for the build get a set of 429 heads, they have better combustion chambers and exhaust. A roller cam adds 500rpm of free power, ie a stock flat tappet is around 4500 rpm a roller can go up to 5000rpm with no change in idol. Run a split duration hydraulic (roller adds about 25hp) cam. Get the crank rods and pistons balanced, a worth while investment. Take the time to Blueprint the engine, can be done yourself to save money. Smoothing the ports is nice but not 100% needed. Run adjustable rockers for rpms above 4500rpms. Built EOD Transmission custom controllers run as low as $150 Transmission about $1200. All of this should get you around 12mpg.