Crower Billet Crankshaft?
- Thread starter SIKDMAX
- Start date
They would run neck and neck. The Lightning has a supercharged engine with great area under the curve. They trap at ~101mph stock, yet are 2000lb lighter, which lines up well with stock LBZ traps of 86mph ish.
math on paper dont add up
http://www.nationaldrivetrain.com/calcs/dragcalc.html iirc setupo for gass
360rwhp
5,000lb is 13.35/97
7,000lb is 14.9/87
http://www.duramaxdiesels.com/forum/calculator.php setup for diesel
360rwhp @
5,000
Your estimated ET is: 12.99
Your estimated MPH is: 103.31
7,000
Your estimated ET is: 14.56
Your estimated MPH is: 92.15
according to those two site diesel is faster by .4th and 5mph
HP is a bye product of tq... not the other way around
RWHP, not crankshaft. The Dmax calculator was based on timeslips for Dmaxes, my 101mph observation on the Lightning is based on track observation, best MPH. Yeah, the Lightnings were underrated from the factory.
Since this is a tech thread,About cranks, has Any one even atempted to answer the thread starter's questions and replies besides my self.......
How did we get into the physics of HP and TQ......... Did RPM call them out?
How did we get into the physics of HP and TQ......... Did RPM call them out?
Since this is a tech thread,About cranks, has Any one even atempted to answer the thread starter's questions and replies besides my self.......
How did we get into the physics of HP and TQ......... Did RPM call them out?
cause torque breaks pistons, rods and cranks... sorry couldn't resist one last thing.
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Well, FWIW, if I was going to go through the bother of buying a new crank, I would go with a stroker. The extra swing is an advantage both in torque and chamber pressures at a given fuel delivery.
The torque is obvious from the longer moment arm. The pressures because of the same increased leverage.
The torque is obvious from the longer moment arm. The pressures because of the same increased leverage.
Thank you, though you may want to inform Pat of the increase in TQ and CP!!! The heads up may help him tune his truck properly...
Jeez-o-pete! All the chest thumping about TQ vs. HP is entertaining. Is anyone listening to anyone else, or have personalities gotten in the way and turned this (already way off topic thread) into a "my dix bigger than yours" contest?
There's nothing to argue about. TQ and HP are first cousins. HP is only a mathematical derivative of torque and RPM. No TQ=no HP (or no RPM=no HP too, just to be fair.
Typically, if a builder wants tons of grunt (a high peak torque number), you will see peak numbers appear in a lower portion of the RPM spectrum. Volumetric efficiency is somewhat simpler to optimize at lower RPM, so peak torque numbers are higher than what you'd see in a similarly prepared high HP engine. GENERALLY speaking these engines lose VE, and thus torque at higher RPM, resulting in ho-hum (relatively speaking) HP numbers. It's a little cliche, but yes, "torque gets it moving".
For the "HP is everything" crowd, well, sure it is. But remember, to get that high HP, you design your build to optimize VE and thus torque at a higher RPM. So in effect, your still building for torque, but at a higher RPM. Now the torque peak numbers you see in these builds is typically less than peak in a grunt motor, because it's tougher to achieve decent VE at higher RPMs. So even though you're not building for bragging rights torque numbers in a high HP build, you are still trying to maintain as high a torque number as possible through a higher, broader portion of the RPM band. To say that torque doesn't matter in a high HP engine is silly. You couldn't show off those high HP dyno sheets without high, sustained torque numbers.
That's why you hear talk about a broad, flat torque curve. Best of both worlds: provide better acceleration from lower vehicle and engine speeds to maximizing vehicle speed (MPH). Any engine which has significant, narrow peaks of either condition (low RPM torque or high RPM horsepower) is gonna be a one trick pony and not fun to drive. Unless of course that's what you want.
Just another one of your post I agree totally with!
I was trying to say the same thing, you just put it in words better.
So let me get this straight. You're saying that if two trucks weighing exactly the same thing with the exact same setup, one with 1000 ft-lbs average torque from 1000 to 1500 RPMs and one with 1000 ft-lbs average torque from 2000 to 2500 RPMs, that if they both lined up and raced that it would be a dead even race?
At the wheels on a dyno. I don't know what you're getting at with the torque at the wheels thing. Does the RPM where an engine makes torque change when it gets to the wheels?
Ok, I dynoed my truck on a dynojet acceleration dyno and it showed 1300 ft-lbs of torque at 2200 RPM and 690 HP at 3000 RPM (which equals 1207 ft-lbs of torque) in 5th gear. Are you saying that I would be faster if my truck shifted closer to the peak torque?
I never got an answer to my question either?
I never got an answer to my question either?