I'm considering building a 300 for my 78 half ton. My dads got one in a 93 and I love it. Gets 18mpg city highway up hill down hill whatever. It's efi bein a 93. So if I build one I wanna do it for longevity and low rpm torque. My question is how much torque and gas mileage can I squeeze out of it. Plans are: 8.7-1 cr hydraulic roller cam (if they make a roller retrofit kit for these) roller rockers, long tube header, p&p head, 3 angle valve job, speed pro hyperuetic pistons, (yes Iknow I spelt that wrong), mad 6a, dui distributor, ditch the flex fan for an electricity one, either an iffy 4bbl intake or a home fabbed tubular one, and a 4 barrel carb.So power potential with this? I figure if I can run all roller cam and rockers It should help it last a long time. What's a realistick mpg to shoot for? 78 half ton short bed 4x4. Will run a np435 and ranger torque splitter I think. 3.73 gears and a 31" tire.

 

Offy intake* not iffy lol

 

FORDSIX PERFORMANCE • View topic - FIGURES

Go through that and you will find computer projections for HP/TQ with various mods.

https://www.ford-trucks.com/forums/3...nline-6-a.html

And that one will show the MPG range of all sorts of 300s.

The roller cam is of no real value unless you are going to run your engine 5000+ RPM under racing conditions. Roller rockers might be a less expensive viable alternative with some long-term ROI.

 

Like Harte3 said, Forget about a roller cam. Unless you've got some really deep pockets and plan to race it there's no need. The last time I checked into it ( 5 or 6 years ago ) the cam and lifters were going to cost $700-$800. So now I would guess it's probably closer to $1000.00. As long as you break in the flat tappet cam correctly it'll last a long time. I've seen more then one stock 300 go past 400,000 miles without a rebuild. A good maintenance routine is far more important then the type of cam you run.


As far as power output that depends on the cam specs and how much you get into the head work. But just guessing by the list you gave you are probably looking in the 200-225 hp range.

And if you plan to run the Advance Adapters Ranger OD unit then I'd go with a 4.10 or 4.11 gear. Unless you plan to do a lot of high speed running with it. Then the 3.50 or 3.73's would be the way to go. I'm going with the stock 3.50 gears on mine with 33" tires. I'm going to use the grany low to get it going and use the tire size and 3.50 gears in place of an OD gear. But mine will be supercharged so there will be no problem with the gears.

 

Thanks for the responses and links. it looks like ill have no shortage of low end torque which is what im looking for. so with the right rear end gears, np435+ranger torque splitter and 31x10.5s i can cruise 65 at 2000 and shoot for upper teens with the mpg. like you guys said the roller cams are way too much $$$. according to that post on fordsix desktop dyno indicates the isky mile a more to do what i want best. i have put alot of tought into a draw through blower or turbo on low boost put i dont know what thatd do for the longevity and mpg. not to mention i dont really wanna buy the premium fuel.what kind of power are you shooting for with your blower set up?

 

I'm not really to hung up on hp #'s. It'll put out what ever it puts out. Just guessing it will probably be in the 275-350 hp range. If it's more I won't complain.

I still have to work out a few details on my build plan. Like the exact cam specs ( I'm going to have a custom grind done by Crower ) , the amount of max boost ( some where between 10-18 pounds ) , how much compression ( some where in the 8.5-9.0:1 range ) and a few other small items. I still haven't decided on if it's going to be a 300 or a 240 ( I've got both ) .

I plan to run it on E85 due to the cost ( cheaper then 87 octane gas ) , high octane rating and cooler running.

And I'm going with blow thru set up thru 3-2V carbs. I want to go blow thru so I can run an intercooler.

I'm going to set it up so if I run into an issue and can't get the E85 fuel. I'll be able to remove the blower drive belt, swap the carbs and re-time the engine and run it on 87 octane gas. But I still want a strong running engine in N/A form. That's why I'm going to go with a slightly higher compression then most would run with a supercharger.


My project is going to be a do it all vehicle. It's going to be my year round daily driver, parts runner, work truck, hot rod, play toy & mild occasional off-roading. It will also be used once in a while to pull my car trailer ( I've got a E350 van for most of the towing ) and maybe even plow some snow in the winter. It's going to be pretty wild for a daily driver but I can live with it.

 

Nothin wrong with a wild daily driver! Im very.... Very tempted to go the forced induction rout. But I'm unsure how the driveability and mpg would be. I can'tget e85 around here unfortunately

 

Driveability isn't an issue. You will use more fuel. But how much depends on your set up and your right foot.

The other option for the fuel is to add a water/meth injection set up. It basically acts like a chemical intercooler. So it can let you get by with lower octane fuel ( to a point ). The down side to this is it's a second system to install and keep filled.

 

If money is not a factor you could probably get some decent power from a propane conversion. Propane requires higher compression so go with 10:1 comp pistons (or just mill the head) and a torque cam like a 262. Top it all off with a turbo. I bet you'd be looking at 50% more power than any stock gasser, plus natural gas is cheaper most places.

 

Double post my bad..

 

I'm lookin into the isky mile a more cam. I have thought about propane though, still considering it. I'd lov e to go turbo

 

Not much relationship between price of natural gas and propane.
Nat gas is low, propane is sky high.

 

I've been researching turbo 300s and I think that's what I'm gunna go with. A turbo off a 6.5 Chevy deisel seems to be the best available from a junk yard. I could maybe go dual ihi off a couple turbo coupes? Anyway intercooled and blowing through a smal 4bbl on a custom tube intake. 8-8.5 cr, unsure on the cam. Stock? Isky mile a more? Custom grind? Roller rockers mild port n polish, forged pistons. Efi manifolds or custom header, msd with the boost retard. 250 hp at the tire on 8-10 psi, lots and lots of torque. From my research 300 hp and just shy of 600 ftlbs at the wheels are attainable on 18psi with e85. I just found one station in my area that sells it.

 

An off-the-shelf turbo cam or custom grind for sure.

Have you thought about swapping on EFI? It shouldn't be too tough with blow through the stock intake and run everything with MS or something. A lot of tuning, but you'll be doing a lot of tuning anyway.

 

I just can't bring my self to go efi on this this truck, just doesn't fit its personality. I have never tuned anything efi before, and carbs I have (although they were n/a) I guy on this forum made 300rwhp and 575rwtq on 18 psi and the stock cam. With the right cam and some headwork I'd like to see 250hp 450 on 10 psi, and 300hp 575-600 tq on 15 psi. This truck has changed directions abit. I've got a 93 f150 for my daily driver now, so this thing can get a little more wild