yeah ive never really understood that. I mean, theres no doubt that the newer diesels out there are making some crazy numbers with relatively low mods, but The 4stroke diesel engine in general, is a low-rpm motor. Why take a power-adder(like a turbo), that is RPM dependant, that THRIVES on higher RPM's.... i understand the free power idea, but a supercharger, being crank-driven would give even more off-idle response. I bet itd be a hell of a workhorse

 

http://www.pickuptrucks.com/html/new...sel-spied.html

 

And thus is the reason you obviously know nothing about turbos and superchargers.Are you saying a supercharger is not rpm dependant? The only difference is a supercharger make boost right away due to the fact it is belt driven that is all.Low rpm is low rpm and the amount of boost that is produced in a turbo compared to a supercharger at low rpm is drastic. The size of the supercharger would have to be enormus to even compare to the boost of a turbo and to top that off there is the issue of compression in a diesel compared to a gas motor. You would have a point if you were talking about gas but your not. As for the longevity of a turbo, 90% of turbo damage is due to a driver and not the turbo. Most of the time when a turbo fails on a diesel the driver has worked the turbo had and has got it hot then shuts the truck right down, what do you think the result will be with a drastic cool down? The turbo fails!!!!

 

Thanks for answering so I didn't have to. Can you say parasitic power loss? Turbo=free HP (well a little bit of back pressure...)

 

He's probably a gas car guy (I hope)! Everyone forgets the little thing called compression and a diesel has a ton of it unlike an 9:1 gas motor.

 

Less power, more mpg please. I want a 30 mpg truck.

 

thats why i said i understand the idea behind free power.

As for being a turbo-god...your absolutely right. ive got a turbo MR2, and thats about the extent of my knowledge.

Are you saying that typically speaking, superchargers are not known for being a more low-end style power adder (off-idle torque), compared to turbos (the reason why my powerstroke really came alive around 2800rpm when the turbo spooled). I never did anything with the powerstroke other than drive it, so I cant really count that as experience.

everyone else is throwing ideas out there. relax...just thinking out loud.

On another note...we had an 18-wheeler fire the otherday. when we opened to front to attack that section, i noticed the turbo. I think it was the size of a geo metro

 

Well based on what can be done with diesels now, a few mods could get you to 28-30 mpg easily ... you have to remember these vehicles have to meet the new epa standards as well

 

250 hp and 325 ftlbs would be fine by me. Design the motor for that and you should be closer to 30 mpg. I don't need any more than that in a half ton. The most I'm going to haul is a car trailer. My 4.6L F150 did that fine.

 

ha ha yer i came all over the back seat. lol

 

HAIRBALL

 

i had a 120 adjustable chip on my dually but i sold it but i haul a john deere 310back hoe on a 47 foot bigtex gooseneck almost everyday of the week and it pulls it just fine with out a chip and unless im pullin a hill with that big of a load im gettin like 12mpg now you get into hills its prob down around 7 but you gotta think thats prob about a 15 thousand lbs back hoe and a ten thousand lbs trailer

 

Turbos are great things, you can trim and size a turbo to make peak power (the turbos peak output power, really CFM) at any reasonable RPM. Be it 1K or 9K. It's simply a give and take. If you're looking to make 1000HP out of a gas motor(2-4L)), you're not going to get that number without a massive turbo and high 7-10K rpms. There are exceptions yes. With a diesel and its nasty compression you can make the same power and a lot more torque with a smaller turbo. A gasoline engine compresses at a ratio of 8:1 to 12:1, a diesel engine compresses at a ratio of 14:1 to 25:1. 14:1 compression in a gas motor is a full out race beast. I think my truck is 17.2:1. Then again I was comparing apples to oranges with mid displacement gas VS double to triple displacement diesels. Why a supercharger would ever be placed on a diesel motor I don't even want to know. Perhaps Ford after having so many problems with the powerstroke wants to abandon the bad consumer report juju. All I know is I'll NEVER drive a gas truck again. And I would kill for a diesel hybrid 3500 that would cut 3cyl at highway speeds. My 17-20mpg now is great. But god how 30++mpg would be SICK in a 11,500lb truck with home brew biodisel at 1.20 a gallon!

If you really want to geek out, better yet, didn't forget all the math you learned, this link has all the turbo nerdness you could ask for.

http://www.turbobygarrett.com/turbob...o_tech103.html

 

Why exactly is ethonal a bad idea?

 

my 7.3 powerstroke has no problems at all. it is the 6.0's that are junk

 

i remember that thing. that is sick. what lift and **** you got on that thing?

 

6 inch lift, 5 inch exhaust, intake
dp-tuner the only way to go on a ford

 

yer i remember that thing its sounds sick to.

 

what are the older rams like then? cummings engine? are they the same asa the newer ones? say like a 97 or are they junk. if i got 1 of them then i could get a lift and **** straight away. there so ******* dear here in the uk.

 

http://search.autotrader.co.uk/es-uk.../search.action