??? Light weight parts lose torque ???

I read on another forum a couple days ago that light weight underdrive pulleys decrease torque output. Which does not sound right. Light engine parts, pulleys, flywheels, CVs, etc... Should allow you to redirect torque to the wheels rather than actually decrease the torque output of the engine right??? Somebody speak on this... :sly:

I have never heard that. But with the underdrive pulleys you will see very, and I mean very little gain. :2cents:

How? How is it gonna reduce your engines output? It ain't. Lightweight parts will not increase your tourque output though. Its will increase your horsepower(NOT CREATE IT!) because the engine can now apply torque at a faster rate due to less mass, this increase is likely to be very small though. A lightweight flywheel can have the greatest effect to an engine, a lightend flywheel can lose your car more than 100lbs in rotational force in first gear.

See thats what I thought. But this guy was totally adamant that a lightweight flywheel would cause his truck to lose torque. Oh well some people.

While a lightened flywheel will reduce the inertia of your flywheel and give your more engine response via quicker revving and rpm slowdown, at a certain level your engine uses this rotating mass to help counteract firing pulses, stop vibration harmonics, and tortional twist. Most 4 cylinders dont use a vibrational damper like v8's so this vibration may be quite noticeable. This vibration (along with being bothersome) can affect your synchros and tranny seals in a negative way, flywheels that have been lightened improperly, or too much, can be bent by the pressure plate on disengagement and cause unnecessary action upon the synchros and thrust loads on the engine thrust bearing and tranny seals. When using lightened flywheels (especially very light ones) it is advisable to balance the crank to assist. Its true that you will notice a difference in power but, without the proper precautions can affect you negatively. Without this rotating mass, say on a flywheel, a driver may confuse the new power output with a loss in torque :bananasmi

Ok, that makes sense as well. Are these kind of problems going to show up in 4 cyl. truck though? Something like a KA24DE Nissan or a 22RE Toyota. Consequently Honda engines do use a harmonic balancer it claims to be attached to the crank pulley.

When I installed an Unorthadox crank pulley on my DX I freed up 6hp at the wheels.. Throttle response picked up a bit, so I don't see how you could lose torque.

While a lightened flywheel will reduce the inertia of your flywheel and give your more engine response via quicker revving and rpm slowdown, at a certain level your engine uses this rotating mass to help counteract firing pulses, stop vibration harmonics, and tortional twist. Most 4 cylinders dont use a vibrational damper like v8's so this vibration may be quite noticeable. This vibration (along with being bothersome) can affect your synchros and tranny seals in a negative way, flywheels that have been lightened improperly, or too much, can be bent by the pressure plate on disengagement and cause unnecessary action upon the synchros and thrust loads on the engine thrust bearing and tranny seals. When using lightened flywheels (especially very light ones) it is advisable to balance the crank to assist. Its true that you will notice a difference in power but, without the proper precautions can affect you negatively. Without this rotating mass, say on a flywheel, a driver may confuse the new power output with a loss in torque :bananasmi

Good lightweight flyweels are balanced and keep the engine rotating smoothly. In 4 Bangers a Power Stroke doesn't happen often enough(180) to create a bad vibration. If your cars engine is not tuned well or another component of the enigne is unbalanced, then this all goes to hell though.

When I installed an Unorthadox crank pulley on my DX I freed up 6hp at the wheels.. Throttle response picked up a bit, so I don't see how you could lose torque.
my unorthodox crank shaft pullie freed up 1.4whp and 2.2tq on my b18c1

my unorthodox crank shaft pullie freed up 1.4whp and 2.2tq on my b18c1
haha d16 > b18 :smokin:

I would definately agree. Throttle response is measurably quicker. And I think we can say that the guy who thought lightweight parts will cause his engine to lose torque was full of it.