found this supposed to be warmed over no serious mods i wouldnt think a cam would add around 100 ft ibs but i could be wrong

 

That's great and all if gears had no impact on road speed. You run out of engine rev's earlier, which means you have to up-shift quicker - loosing any torque advantage. So a 4.9 with 4:10s will get out of the hole decently, but you have to shift into 2nd at 19 MPH, and any advantage is lost.

I've done large charts calculating torque at the wheels vs road speed before, and on certain engine combinations - 3.55:1 gears actually offered more torque at key road speeds then 4.10:1 did, solely due the nature of what gear the transmission could be in at a certain speed.

I'm done with this thread anyways, It's clear you were looking for people to tell you that the 4.9 is a purposely under-rated 300HP monster towing engine.

 

no i was just wondering if anyone ever dynoed a stock motor because car companies have been known to shave power ratings down for better insurance it was you who got your panties in a bunch and made this thread a bunch of jumble bull

 

i know it wont be a 300 hp monster towing engine see if you knew anything about towing you would know that TORQUE is where it's at not hp and the 4.9 is a towing motor so it there fore has low HORSEPOWER but makes more TORQUE

 

That motor sounds like it has higher compression and a host of other mods. That carb--what you can see of it--isn't stock. There is no text or other info on that video to inform the viewer of anything. Where did you get the extra 100 ft/lbs from?

 

it said it was making 350 ft ibs of torque which would be close to 100 ft Ibs of torque above stock

 

You will find, in most cases, the factory rating is actually HIGHER than what the vehicle actually makes. I have had friends take their cars to have them dyno'd before modding only to find that the car makes LESS power than it is supposed to. This is the case even after accounting for the difference between flywheel HP and wheel HP.

 

what kind of cars

 

No. You need to learn what exactly horsepower means, and what it does. Torque is twisting force. I can change the amount of twisting force to my rear wheels using my gearbox and transfercase. There are even cases where an F-250 5.4L V8 6spd can put more torque to the ground in 1st than a 7.3L PSD F-250 automatic.

You can't change horsepower with gearing, and once you understand the relationship between horsepower and torque and RPM (HP=Torque*RPM/5252), you'll understand that a higher horsepower engine can stay in lower gears at higher road speeds and deliver more torque to the ground. I did the math once - a 4.6L Expedition is actually capable of putting more torque to the ground at almost any road speed (except from 0-20 MPH, but I don't spend much time at those speeds) than a 460 powered truck. Simply by the virtue of having a higher horsepower engine with gear ratios optimized for it.

The 4.9 is not a towing motor, if it was, it'd have more than 265 lb-ft of torque and much more horsepower. The 4.9 is an economy engine that happens to have good off-idle grunt. By 2000RPM, a 302 is making more torque. That off-idle grunt is good for getting a load moving, around-town drivng or maybe pulling a stump out, but that's about. At any normal road speed, a 302 can put more torque to the ground.

 

really the 4.9 is not a towing motor huh just by thought does it make any sense to put an economy motor in umm say tractors, combines.... DUMP TRUCKS that really seems like the kind of vehicle you would put an economy motor. if ford wanted to have an economy motor they would have thrown in a 4 banger never mind it was the standard engine in the 1/2 3/4 and one ton pickups and in the e series vans

 

by the way torque is the ability to get an object moving and hp is the ability to keep that object moving straight from hot rod magazine there bud

 

The 300 was used in agricultural and medium duty trucks due to the fact it was reliable, simple, and fuel efficient. All those vehicles listed have additional gearing to keep the engine in it's peak power band. Almost all older dump trucks and tractors had 2 speed rear ends in addition to the primary transmission.

The 300 was never under-rated from the factory because there was no reason to. Trucks are not sports cars, therefore the power rating has zero impact on insurance. I think that you may be thinking of how the Buick Grand National and the Syclone were under-rated by GM, but there was a reason behind it (hint, NOT for insurance); The Corvette was supposed to be the top dog, and it would be bad business sense to sell a more powerful car/truck that cost less and had a lower profit margin. All manufacturers do it, even the Japanese. For the longest time there was the gentlemens agreement that capped power at 276hp. Were there cars pushing more? Of course there were.

Another thing to consider: if you take any muscle car from the 60s or 70s and dyno them using the new SAE standard (or even SAE net), they will be making LESS power than they were rated for. Reason being the old system (SAE Gross) didn't have any emissions equipment, exhaust, air cleaners, etc installed. If anything, your truck is making less power now than new due to wear and age. Also factor in the standard 20% driveline loss.

The 300 is what it is, a reliable, efficient engine. A 4 cylinder would be pointless in a f/s truck since the fuel economy would be worse as it would be under full load almost all the time, whereas a larger engine doesn't have to work as hard to move the same amount of mass. The 300 gets the job done for the majority of the population out there, however if I plan on pulling a heavy load I'm going with more displacement.

 

My buddy's 2011 Camaro is a prime example. It's a SS trim with 426 Hp from the factory. When run on the local dyno it only made ~380hp at the flywheel after correction. Even after mild tuning it didn't make the factory ratings. And as far as the HotRod magazine thing is concerned, that is a really dumbed down way of putting it. Sure it is on the right track, but I'll trust math and physics long before a car magazine. The way I see it, you can spend a bunch of money trying to make a 300 a towing vehicle. That's fine. While your doin that I'll spend half the money and put a cam and headers on my 351 and be way ahead of that 300. The 300 has its place, just not in a truck towing big loads.

 

Economy is critical to tractors and combines, as is durability. They want a low-revving, long-lived engine that is not too bad on fuel. Otherwise you can't make money if you're shoveling tons of fuel into the thing. The 4.9 is an economy engine, it was the base engine. It was the cheapest to purchase, the cheapest on fuel, the cheapest on maintenance and the lowest on performance.

Most large gasoline dump trucks of the 70s and mid 80s (before diesels really fully took over) ran Chevrolet 454s or something like a Ford 477 or 534 V8.

Yeah, that's just a bunch of nonsense. I'll trust my physics book that the very engineers who design engines, transmissions and vehicles read, over Hot Rod magazine.

 

im not saying that it wasnt a economical motor in the terms of durability and and low operating cost i am saying that its not a fuel efficient motor i completely and totally agree that it is durable and cheaper to maintain. also i dont think the motor gets the credit it deserves in respect of what it can due if it was put in to machines listed above. all i want to know is if anyone has dynoed a factory motor to see if the numbers are accurate. also to Evan P go ahead and build that 351 and then we'll meet except i use my other grandpa's 400 big block backed by a 4 speed and kick the crap out of any 351 you can build for absolutely no cost to me. dont try and say your built 351 will out pull my grandpa's 400 as its built up the a** and regularly hauls tripple axle gooseneck trailers loaded with all sorts of crap with no problem. ohh did i mention it was a 78 f150 custom. just so you dont say that there is no way a 150 will handle that he built it using aftermarket parts with a 2 ton trucks weight rating