Truck Mods for more power and torque

pronstar · November 13, 2018

Gears multiply the engine’s torque.

Gearing changes affect torque multiplication, which is directly related to power transmitted to the ground.

A lower overall gear ratio (which takes tires into account) offers more torque multiplication.

Confusingly, lower gears are higher numerically.

And taller gears are lower numerically.

Sent from my iPhone using Tapatalk Pro

aseibel · November 13, 2018

1 hour ago, greatmizzou said:

Interesting. I wonder if that’s why 1/2 ton trucks of 2002 have LT tire ratings at 245/65/15 instead of 265/65/15

That's barely going to change anything. The first number is the width of the tire in mm. The second is aspect ratio. Your two tire sizes are a whole 4% different in diameter. So the smaller tires would make it feel like you had 4% more torque than the larger tire.

https://tiresize.com/comparison/

greatmizzou · November 14, 2018

2 hours ago, aseibel said:

That's barely going to change anything. The first number is the width of the tire in mm. The second is aspect ratio. Your two tire sizes are a whole 4% different in diameter. So the smaller tires would make it feel like you had 4% more torque than the larger tire.

https://tiresize.com/comparison/

4% is more then most bolt on mods lol.

aseibel · November 14, 2018

13 hours ago, greatmizzou said:

4% is more then most bolt on mods lol.

true dat. So changing to a smaller tire size is probably the best bang for your buck to gain torque. Too bad almost no truck owners want to to this.

greatmizzou · November 14, 2018

1 hour ago, aseibel said:

true dat. So changing to a smaller tire size is probably the best bang for your buck to gain torque. Too bad almost no truck owners want to to this.

I think this thread helped convince me to do the LT245 tire, as recommended by the manufacturer, when I upgrade to a towing tire. I might lose an inch in tire height, but I imagine the additional lower center of gravity will help me even more. I’m not a fan of flashy lifted trucks and I like to keep things stock anyway.

intheburbs · November 14, 2018

2 hours ago, greatmizzou said:

I think this thread helped convince me to do the LT245 tire, as recommended by the manufacturer, when I upgrade to a towing tire. I might lose an inch in tire height, but I imagine the additional lower center of gravity will help me even more. I’m not a fan of flashy lifted trucks and I like to keep things stock anyway.

If nothing else, you're find a much broader selection if you go to 245/75/16 tires. My '01 half-ton Suburban came with 265/70/16, but once I started towing with it I switched to 245/75/16. Very slightly smaller diameter tire, but tons more choices in brand, especially for E-load LT tires. My '08 3/4-ton Burb came with 245/75/16 as the OEM tire.

swathdiver · November 14, 2018

On 11/13/2018 at 11:22 AM, cgarldt11 said:

Are you saying that the bigger tires are making me lose horsepower and rpm's in the engine?

Certainly not. However, those larger tires are not allowing all of that power to be used to the same mechanical advantage as before with the original sized tires. Re-gearing restores those losses.

TXGREEK · November 16, 2018

Are you saying that the bigger tires are making me lose horsepower and rpm's in the engine? I am not the smartest mechanic, nor I claim to be one, but I dont think that is correct. I could be wrong though.

He’s absolutely correct. I’ve got an 18, 6.2 and noticed a bit of slower acceleration after I put on bigger, heavier tires. Best thing to do is get a tuner. I’ve already noticed increased HP and Torque after the tuner. Good luck

Sent from above

pronstar · November 16, 2018

Your engine isn’t making less or more power with gears/tires...flywheel hp stays the same.

Gearing and tires are all downstream from the engine, and effectively alter how much engine power gets to the ground.

Grumpy Bear · November 16, 2018

Wiki: A pound-foot (lbf⋅ft) is a unit of torque (a pseudovector). One pound-foot is the torque created by one pound of force acting at a perpendicular distance of one foot from a pivot point.

It produces no movement. It does no work.

Wiki: The foot pound-force (symbol: ft⋅lbf or ft⋅lb) is a unit of work or energy in the Engineering and Gravitational Systems in United States customary and imperial units of measure. It is the energy transferred upon applying a force of one pound-force (lbf) through a linear displacement of one foot (read the red portions as a single thought)

Perpendicular distance is the length of the lever. Linear distance is the displacement away from it's point of origin.

A pound of force applied to a bar one foot in length moves nothing. No work is done. Energy that moves a pound of material one foot does. A ICE's torque is the measurement of energy, not force. IF the component of time is added such as moving a load of material over a distance in some time then we call that horsepower. If you move 550 pounds a distance of one foot in one second that's one horsepower. If you move 5-1/2 pounds over 100 feet in one second that is also one horsepower.

To move a load you need enough ENERGY to displace the load/mass/weight the required distance. Gearing supplies the means to multiply the ENERGY. Provide movement.