anyone ever notice that diesels take a ton of boost from a turbo to make power not hating but i mean yeah ur diesel makes 800 ft pounds with at least 20 pounds of boost. put 20 pounds of boost on a gasser and it will make way more power. considering there are motors making way more power with less boost

 

easy tiger.
you can force induct a gas job,but it's not going to be so easy on fuel as a diesel.
diesels are working engines.sure some guys now buy them just for fun (it surprises the hell out of me how many still,even in the new economy but its very good to see so many still so fortunate) but many of us are out there putting their low end grunt advantage to use getting decent fuel economy while hauling/towing loads that would make a gas engine scream and cost you at the pump.

 

i know they make good torque and get better gas mileage but i'm just sayin power wise a turbocharged gas motor would make more power admittedly at a higher rpm for most engines unless you had a turboed 300 inline six but those have crappy flowing heads so power potential is pretty limited

 

i don't see how that makes diesel engines suck.everyone's entitled to their opinion.

 

i know its my opinion but without a turbo a diesels make no power just kinda thinking out loud that a turboed gas motor would make more power than a turbo diesel assuming all the variables the same (head flow turbo psi etc.)

 

i disagree with the right tune a gasser will get better gas mileage than stock. it does decrease power a little bit

 

Are you saying that a different tune will yield better fuel economy or that a forced induction motor will?

If you leave all else the same, yes, a tune can help with fuel economy. Both modern gasoline and diesel engines could be more fuel efficient if emissions weren't a concern. There are a lot of concessions made in the tune, and a lot of efficiency wasted in the after treatments (catalytic converter, particulate filters, DEF, etc) that rob power and decrease efficiency for the sake of cleanliness.

In the case of a forced induction gasoline motor, they will inherently get lower fuel economy than it's otherwise exact copy naturally aspirated motor. That is due to forced induction motors having a high BSFC (base specific fuel consumption). The way to alleviate this is to run a smaller engine with higher boost levels; ie the new Ecoboost motors.

As far as diesels "sucking" compared to gasoline motors, it's kind of an apples to oranges comparison. While both gasoline and diesel motors serve the same relative purpose in a truck (move a load), they both approach it from different, but equally valid, angles. Yes, gasoline motors, especially if designed with forced induction, will make more power, but it'll occur at a higher RPM range. This is great for small cars or the occasional sprint, but in long hard pulls up a mountain side (pulling a camper), a diesel is going to have the distinct advantage by not having to rev at high RPMs for an extended period of time. A gasoline motor will do it, but it'll make for higher wear and tear on the already lighter components of the gasoline engine. Diesels deal with the stress better due to their heavier parts, the lower RPM, and the lack of worry for pre-ignition and detonation as the combustion chamber warms up.

Personally, I'm sticking to my 460. Plenty of power but definitely not as much torque as a diesel can produce in low RPM ranges for extended towing. However, I also don't have the maintenance cost associated with the diesel engine.

 

You're really contradicting your argument here. With a diesel you get power AND fuel mileage. You don't have to pick a side.

 

You are moving into troll territory.

Your other post is a fine display of your genius and broad understanding of the internal combustion engine, on par with your understanding of the English language and it's uses.

https://www.ford-trucks.com/forums/1...ine-power.html

My guess is that you are 14.

 

Where did this thread come from? A turbo gas engine will probably make more HP than a turbo diesel, but no way in hell will it make more torque. With a truck application, HP really isn't on most people's minds. For a truck it more about torque and producing torque at lower RPM's. That's what most people look for at least. This brings me to your point of 20 PSI of boost in a gas engine and 20 PSI in a diesel. You may get more HP out of the gasser, but almost guaranteed you won't come close to that 800ft-lb of torque. And even if it did it wouldn't be making it till much higher in the RPM range. That 800ft-lb in the diesel, which I assume is pointing towards the 6.7 powerstroke, is there at 1600 RPM. In a gasser the turbo wouldn't even be close to spooling up. The other thing to think about is the other work required to run these boost levels. With most diesels, other than some tuning, and maybe injectors, you can run that turbo at 20 PSI all day long and still get decent fuel mileage. Withe that gasser, in most engines, you will be rebuilding the entire bottom end to handle that much boost at the RPM's that would produce power like the diesel. Not to mention, once the turbo is spooled up to that 20 PSI the engine will be at a much higher RPM requiring much more fuel to be used. So at the end of the day, diesel's do NOT suck. They have their well earned place. Saying that they need turbo's to make power is valid. HOWEVER, the trend of today's gas engines seems to be creating power with turbo's as well so you can't just dog of the diesels anymore.

 

O-boy, yur numbers are adding up quick ...

All things being equal, Diesel delivers more BTU per unit then Gasoline.

Thus delivers more power per unit then gasoline ...

Thus all things being equal will BLOW THE DOORS off a gasser!

EOS!

-Enjoy
fh : )_~

 

Ive had a rough few days.. These 2 threads just brightened my day with laughter.

 

20 lbs of boost on a 4 cylinder will give you 400 hp and 200 lbs torque at 9,000 rpm.
a naturally aspirated 7.3 only makes 185 hp at 3000 rpm, but it also makes 360 lbs torque at 1400 rpm. so while it is not a race car, it will do anything you ask it to do. just not fast.

 

that tread was just a jumbled mess. all i wanted to know is if someone threw a stock 4.9 on the dyno and see what they made and apparently i started something

 

How many gas semi-tractors do you see? Why?

You can talk all you want about turbos and fuel economy, but the reality comes down to the difference in how the two fuels burn. Flame-front propagation is much quicker in gasoline, making it better suited for higher-RPM applications. Diesel burns much more slowly, requires higher temperatures and pressures to ignite (but it actually burns cooler than gasoline in open air), which means it can be run at much higher compression ratios--roughly double that of a gas engine. Note that gas engines are typically in the 9-10:1 ratio if naturally aspirated (20:1 for an NA diesel) and 6-8:1 for an induction setup on a gas engine (16:1 for an induction diesel). For those much higher compression ratios, stronger, heavier engine components are needed, which are less of a factor on a much heavier truck. So, to make the same power and torque, a gas engine has to be spun up--which is more wear and tear on those lighter components.

Jason

P.S. Low-RPM torque is what gets loads moving from a stop, which is how diesels excel. Also, the higher compression ratio gives much better engine braking, which is almost a necessity with heavy loads if you want your brakes to last any significant amount of time.