Hi, I really would like to build a hi-torque, good horsepower truck. First, I was wondering if there are any cheap (under 1k) upgrades. Secondly, am I better off with 4.9L straight 6 or a 7.3L diesel? I can get both reasonably. I also need fuel economy due to it will be a commuter. Thanks.

 

First, welcome. For upgrades under $1000, I would suggest a holley carb, offy intake and headers. Still, it won't be as powerful as a 7.3. When it comes to economy, they are respectable. I don't know what the diesel gets or what vehicle it is going in, but I get about 13-14 with a lifted, low geared 4x4 and a manual trans. One guy here that has a really nice 300 is Col Flashman. I am sure it was over a grand, though.

 

I'm pretty sure Cols was a little over 4 grand.

Take the amount of money you want to spend on the engine, a grand. A grand in the 7.3 will end up with more h.p. and tq than a grand in a 4.9. As for economy, Im sure different years 7.3's get different economy. 4.9's all have different mileage, some get 18 some get 9. A 7.3 on average might get the same economy as a 300, a newer 7.3 will get better I'd think, plus a grand in it and you'll have great hp and torque. Both motors last forever, ones fuel is 1.93/gal. and the others is 3.07/gal. It all depends really.

Just think in a newer 7.3, a 400 dollar chip gets you 110 h.p 200+ ft lbs. For torque and horsepower diesel seems the way to go now days.

 

for my landscaping/construction company, I drove an 88 300/6 for 6 years.
dang truck was perfect, I bought it for $1700, drove a heck of a lot of hard miles and sold it 6years later for $1200. Never even touched the valve covers. Truck would have been another 5 trouble free years if I kept it, but I needed a heavier truck and the 300/6 was in a f150.

so I bought a 7.3 idi in an 89 f250. 10,000miles later, a turbo and a few other fix it things, truck rocks. I'm addicted, and don't think I could go back to a gas engine.
the 7.3 is more expensive tho. starter was $130, fuel is more ect.

if it were my pick for business, I'm with the 7.3idi (not powerstroke).

few figures and facts:
reman engine: 300/6 $1,200 7.3idi $4,000
my 300/6 was in a 4,000lb truck with 2.73 gears with a c6, 14mpg
my 7.3 in a 7,500lb truck with 3.55gears and a c6, 15.5mpg (doesn't change regardless of load, ie 12,000lb load got me 13.4mpg)

maintainance costs:
300/6 over 6 years, $900
7.3 over 1 year, $560
don't forget you use twice as much oil in a 7.3 also.

for straight reliable work, I'd trust either one. If you are just driving around town get the 300/6, it'll be cheaper. If you need a heavier truck that can haul 3,000lbs in the bed, get the 7.3

drew

 

$1k won't even rebuild the injector pump on a 7.3

 

Injector pumps for 7.3 and 6.9 are around $300 now. Times change and prices have fallen.

 

on a powerstroke it'd be $1000 or more.
these IDI engines are cheap for a diesel.

 

I had a 7.3 idi non-turbo and now have a 300 6. If you are looking for pure toqrue, the 6 will not compare to the diesel. The only facts I have are from pulling out trees and climbing hills while huntin. The 6 is great and can get me anywhere, but can not pull out trees like the diesel could. For upgrades, I sepnd $1000 cdn and got headers and dual exhaust for the diesel. What a difference. When I was empty, the best milage I got was 24 mpg. reg cab, long box, 4x4, canopy, auto (E40D) and 4.10's )according to the sticker). The reason I got rid of it is taht it had 300,000 kms on it and needed the whole front end redone and my dad was getting rid of his 6 and it is a 96 with 120,000 kms on it and he traded straight across, so I couldn't say no.

A powerstroke will cost you some serious coin if it breaks, and I found that everything for the idi was more expensive as well. But the torque was worth it Hope this helps.

 

You do realize that, in general, horsepower and fuel economy are inversely related right? In other words you make horsepower by using more fuel. There are a few things that will increase both. Vacuum and electrical repairs, tune ups, cold air kits, balancing, and recurving the distributor on a modified engine come to mind.

 

Good all around truck for commuting and work get the 300. You might have to make an extra trip for hauling than the torque monster 7.3. But when it comes to all around commuting or driving to work the 300 takes the cake. I always thought you cant compare a 7.3 with a 300. Way more torque and horsepower, but if you need it to go fishing or groceries or commuting around in the city your lookin a big bucks for fuel, like the others said the repairs as well. I know what i'd pick.

 

Actually, I've seen big block chevys with holley fuel injection kits make 15 mpgs, hell the new vettes make mid 20's, while makeing a little under what, 400 horses?

Of course, you can gear the 300 to the moon, hook it to a ZF, which has a granny first and overdrive, then you'd have some good torque and mild economy, not as much as the 7.3, but oh well, I'd rather buy fuel for 1.92 than 3.09.

 

Don't forget, we're talking about trucks here. Over 4000 pounds, 30 some square feet of frontal area and a .6(about) drag coefficient. Weight hurts gas mileage during acceleration and frontal area and drag coefficients hurts gas mileage all the time. Almost any car can do better than a truck because they have less frontal area, better drag coefficients, and/or less weight. So a corvette is a bad example.

 

either way, strictly on a gas/fuel prices, im blow away at what some of you all pay. my 300 will avg 20 mpg. cant complain really. my expedition 5.4 gets worse. but we're payin 2.14 a gallon for gas, and i think its around 3.26 for diesel. gas hasnt been this low since before summer...wow

 

What tranny/gears/tires are you running.

I've got the M5OD/3.90/235's and only getting 16mpg on a good day. Every once in a while I'll get 18. Granted my 300 is a little tired.

 

Anything you do to the engine to make it more efficient will help both power and mileage. Most things that "add power" don't really add power, they just keep it from being wasted on something useless. As a general rule, nothing you do to the engine will hurt mileage unless it changes the manifold vacuum at idle. The exception is if the part you change is poorly matched to the rest of the combination.