Please edjucate me on TQ ratings?? Thump?
#1
Please edjucate me on TQ ratings?? Thump?
I have heard people say that changing your gear ratio will have no affect on dyno torque ratings?
How can this be?
I can see that gear ratio's have no affect on HP and TQ ratings at the flywheel. Obviously
And I can see that gear ratio's would have no affect of Rear wheel HP.
But how is it possible that lower gears do not give me more torque at the tires on the pavement?
It seems to me that it does.
Or maybe I have just misunderstood some that said that it dosen't give more torque at the wheels.
Just wanted to get your attention Thump cause I seem to remember you in the conversation a while back.....several months ago at least...
How can this be?
I can see that gear ratio's have no affect on HP and TQ ratings at the flywheel. Obviously
And I can see that gear ratio's would have no affect of Rear wheel HP.
But how is it possible that lower gears do not give me more torque at the tires on the pavement?
It seems to me that it does.
Or maybe I have just misunderstood some that said that it dosen't give more torque at the wheels.
Just wanted to get your attention Thump cause I seem to remember you in the conversation a while back.....several months ago at least...
#2
The only thing it changes is TQ versus road speed. Think about it. The lower the ratio (higher the number) with the same tire size the lower the speed the torque curve is at in each gear.
A torque curve is constant. You have a certain TQ value at any given engine RPM. The only way to change a torque curve is with tuning or mods such as intake, exhaust, cams, efans, underdrive pulleys, etc. I suppose you can change the TQ value at the rear wheels with tranny mods.
A torque curve is constant. You have a certain TQ value at any given engine RPM. The only way to change a torque curve is with tuning or mods such as intake, exhaust, cams, efans, underdrive pulleys, etc. I suppose you can change the TQ value at the rear wheels with tranny mods.
Last edited by glc; 09-25-2008 at 01:01 PM.
#4
The only thing it changes is TQ versus road speed. Think about it. The lower the ratio (higher the number) with the same tire size the lower the speed the torque curve is at in each gear.
A torque curve is constant. You have a certain TQ value at any given engine RPM. The only way to change a torque curve is with tuning or mods such as intake, exhaust, cams, efans, underdrive pulleys, etc. I suppose you can change the TQ value at the rear wheels with tranny mods.
A torque curve is constant. You have a certain TQ value at any given engine RPM. The only way to change a torque curve is with tuning or mods such as intake, exhaust, cams, efans, underdrive pulleys, etc. I suppose you can change the TQ value at the rear wheels with tranny mods.
As I understand, when a vehicle gets' dyno tested.....Calculations are made for drivetrain loss, etc, so that the dyno sheet is supposed to represent the HP and TQ numbers that the motor creates at the flywheel. Is this correct?
But if I have a 1 HP motor geared really high....won't I have very low torque at the wheel vs. a 1HP motor geared really low....won't it have higher torque at the wheel?
If you try to hold a 10 speed tire still while I pedal in 10th gear you may be able to hold it.
But if I have it in 1st gear you won't be able to because I will be able to put more torque on the tire.
The same should apply if I re-gear a axle. All of a sudden 1st gear is much lower than 1st gear used to be so I should be able to gain more torque with the same motor.
#6
My brain can comprehend physics better than spelling.:o
Well I think it does......untill someone completly shoots me down on my above logic..
#7
Trending Topics
#10
No I know the engine dosen't change at all.
But sometimes don't manufactuers talk about HP and TQ at the pavement?
An vehicle can produce 300 hp at the flywheel and only have 230 or whatever on the ground due to drivetrain loss. Just like an engine can produce 300 Foot LBS of torque at the flywheel and only put 230 on the ground. Lets say this vehicle has 3:73 gears
Can it be assumed that re-gearing from 3:73's to 4:88's could make the vehicle still produce 300 foot lbs at the flywheel but now produce 280 ft lbs(made up number) on the ground?
But sometimes don't manufactuers talk about HP and TQ at the pavement?
An vehicle can produce 300 hp at the flywheel and only have 230 or whatever on the ground due to drivetrain loss. Just like an engine can produce 300 Foot LBS of torque at the flywheel and only put 230 on the ground. Lets say this vehicle has 3:73 gears
Can it be assumed that re-gearing from 3:73's to 4:88's could make the vehicle still produce 300 foot lbs at the flywheel but now produce 280 ft lbs(made up number) on the ground?
#12
#13
The truck is producing more torque. But the motor isn't.
Last edited by efuehrin; 09-25-2008 at 03:34 PM.
#14
Take a Samurai for instance. Something like 50 ft lbs of torque (stock at the motor). yet through all the gearing we do to them, they can break your neck, and pull tractors around in the field. With out gearing, you can BARELY move it on 33" tires. Granted, we can now only go about 25 mph MAX, but you don't need any more speed then that !