4agze crank pulley

[speedmaster]

Be it OEM or Cusco oversized 175mm crank pulley. Does it effect the torque if using them on 4age or 7a engines?

[jondee86]

If the GZE crank pulley is being used on a NA 4A or 7A engine, there will
be two minor downsides...
1. The accessories being driven off the larger ring will run a bit faster
than they would have done with a 4A or 7A pulley, and
2. The GZE pulley will have slightly more rotational inertia than a 4A or
7A stock pulley.

As to affecting torque; at a steady rpm on a dyno, the inertia of the
pulley has zero affect on torque. But in a situation where the engine is
accelerating rapidly on the road in first gear or on a inertia (rolling road)
dyno, there will be some small negative effect from the greater inertia
of the GZE pulley.

The torque produced by the engine has to accelerate every rotating part
which includes accessories, flywheel, gears, driveshaft, axles wheels and
tires. If you increase the rotaional inertia of any of these parts, a little
bit more of the engine's torque goes to accelerating the part, and a little
less reaches the treads for spinning up the dyno roller.

Any effect from the GZE pulley would only be likely to be felt in first gear
on the road... the effect gets less as you move up thru the gears. For a
4th gear dyno run, you would lucky to detect any difference between the
stock 4A and stock GZE pulleys. The Cusco pulley being bigger, and no
doubt having higher inertia, could make a noticeable difference.

Read what it says here...
http://www.mr2ownersclub.com/mr2sc/webs ... /crank.htm
... at the bottom, when the guy changed from a Cusco to the same size
aluminum pulley. That's inertia for ya

Cheers... jondee86

[yoshimitsuspeed]

Are you asking if increasing boost will increase torque? It seems like this would be pretty self explanatory.
Or are you asking about reducing the mass of the pulley as jondee86 described?

[speedmaster]

If the GZE crank pulley is being used on a NA 4A or 7A engine, there will
be two minor downsides...
1. The accessories being driven off the larger ring will run a bit faster
than they would have done with a 4A or 7A pulley, and
2. The GZE pulley will have slightly more rotational inertia than a 4A or
7A stock pulley.

As to affecting torque; at a steady rpm on a dyno, the inertia of the
pulley has zero affect on torque. But in a situation where the engine is
accelerating rapidly on the road in first gear or on a inertia (rolling road)
dyno, there will be some small negative effect from the greater inertia
of the GZE pulley.

The torque produced by the engine has to accelerate every rotating part
which includes accessories, flywheel, gears, driveshaft, axles wheels and
tires. If you increase the rotaional inertia of any of these parts, a little
bit more of the engine's torque goes to accelerating the part, and a little
less reaches the treads for spinning up the dyno roller.

Any effect from the GZE pulley would only be likely to be felt in first gear
on the road... the effect gets less as you move up thru the gears. For a
4th gear dyno run, you would lucky to detect any difference between the
stock 4A and stock GZE pulleys. The Cusco pulley being bigger, and no
doubt having higher inertia, could make a noticeable difference.

Read what it says here...
http://www.mr2ownersclub.com/mr2sc/webs ... /crank.htm
... at the bottom, when the guy changed from a Cusco to the same size
aluminum pulley. That's inertia for ya

Cheers... jondee86

Thanks bro for that

[speedmaster]

Are you asking if increasing boost will increase torque? It seems like this would be pretty self explanatory.
Or are you asking about reducing the mass of the pulley as jondee86 described?

For non Supercharged