Lightweight pulley wow

[oso_25]

Hope this won't be a personal preference thing like u want a better response or balance engine?

[xwd]

Originally Posted by 20valvewynn83

I know that for Toyota they normally have an internal balance shaft (two) but this eng im not too sure of. Also so you all know Toyota also uses a different type of belt tensioner to Reduce vibrations. this eng has that type of tensioner so i would say it would be safe to use. Toyota use to use harmonic balancers but then stopped.

H4/H6 Subaru engines do not use balance shafts. The whole car minus the transmission and rear diff is Subaru.

[exmayol]

Nice mod, great value. Whenever I get my BRZ this will be one of the first on my todo list. I've been running one on my RSX for at least 30K with no problems whatsoever.

[DrDuquette]

What about all the other pullys?

[Bonburner]

Originally Posted by DrDuquette

What about all the other pullys?

I've constantly thought about this myself .. I saw a picture of a Japanese modded car where they have All been replaced ~ !

[DrDuquette]

Originally Posted by Bonburner

I've constantly thought about this myself .. I saw a picture of a Japanese modded car where they have All been replaced ~ !

Why is this the ONE pully that is being replaced and not the others? And how can such a small amount of weight make a noticible difference as compared to changing all of them or the fly wheel? Also. A little worried that the original one has a rubber dampener. Is there a good reason for that?

[Sportsguy83]

Originally Posted by DrDuquette

Why is this the ONE pully that is being replaced and not the others? And how can such a small amount of weight make a noticible difference as compared to changing all of them or the fly wheel? Also. A little worried that the original one has a rubber dampener. Is there a good reason for that?

This one pulley is the only one in the same axis as the crank, so it's the one that will produce the biggest gains to reduce weight. Changing the flywheel would mean even more gain, but to remove the flywheel you need to detach the transmission while for the pulley its a 10 minute job. As far as the rubber damper, read the thread, it has already been answered.

[Bonburner]

Originally Posted by sportsguy83

This one pulley is the only one in the same axis as the crank, so it's the one that will produce the biggest gains to reduce weight. Changing the flywheel would mean even more gain, but to remove the flywheel you need to detach the transmission while for the pulley its a 10 minute job. As far as the rubber damper, read the thread, it has already been answered.

Sure that is the First pulley but that very pulley is pushing the rubber belt which pushes the other pullies.
If all of them have been changed to lighter ones then it'd be better than just 1 pulley.
I still don't understand why it's just one pulley being changed :/
I'm sure if you replace all of them you can get a lot of weight off

[Sportsguy83]

Originally Posted by Bonburner

Sure that is the First pulley but that very pulley is pushing the rubber belt which pushes the other pullies.
If all of them have been changed to lighter ones then it'd be better than just 1 pulley.
I still don't understand why it's just one pulley being changed :/
I'm sure if you replace all of them you can get a lot of weight off

No one has said that there is benefit ONLY in changing this one. This is the only one being changed because its the only one available at the moment. (No one else is selling a kit or something to change them all). Also, you cannot go too light on this components because it can trigger diagnostic codes on the ECU.

Edit: But honestly, I am not too sure how much benefit there is from changing the other pulleys. Remember, changing the crank one equals removing weight from the crank. Removing weight of all others is just removing mass off axis and I don't see much benefit in that. (There is some benefit sure, but I don't think its a lot).

[Bonburner]

Originally Posted by sportsguy83

No one has said that there is benefit ONLY in changing this one. This is the only one being changed because its the only one available at the moment. (No one else is selling a kit or something like that). Also, you cannot go too light on this components because it can trigger diagnostic codes on the ECU.

Mmm, forgot about the ECU pestering ..
well I plan on doing a flash one day ... I guess that's when I'll swap them all out.
hopefully that takes care of that

[DrDuquette]

Sorry. I didn't read the whole thread about the rubber dampener.

But it shouldn't matter which pully is made lighter. Anything that the belt TURNS could bennifit from being lighter or removed. It all weight that has to accelerates or decelerate buy the rest of the engine. Example, remove the AC compressor.

But now go deeper. So anything that is turned buy the engine can bennifit from wieght reduction. That's why we talk wheel weight and size too.

[Sportsguy83]

Originally Posted by DrDuquette

Sorry. I didn't read the whole thread about the rubber dampener.

But it shouldn't matter which pully is made lighter. Anything that the belt TURNS could bennifit from being lighter or removed. It all weight that has to accelerates or decelerate buy the rest of the engine. Example, remove the AC compressor.

But now go deeper. So anything that is turned buy the engine can bennifit from wieght reduction. That's why we talk wheel weight and size too.

Yes, again, I am not saying there is no gain in reducing the other pulleys, but it I'm pretty sure the result gain won't be as big as reducing the crank pulley.

Edit: Let me put it this way, I'm sure there is gain and at the right price makes sense to go for it. But care needs to be taken regarding ECU accidentally believing misfires are happening.

[jedibow]

Originally Posted by Nezz

Hm. On second thoughts I don't think my pulley's getting changed-- those drill marks are balance marks...

The perrin unit is balanced also...

[86drift]

Originally Posted by sportsguy83

My question to anyone with way more knowledge than me is: are those balance marks of just the pulley being balanced, or are those marks of the pulley being balanced together with the crank, rods, pistons, flywheel?

I'd like an answer to this before I install a LW pulley. When I have an engine built it is balanced together.

One of the things I first noticed driving this car was the slow reactions of the engine due to flywheel (and pulley) weight. I find my gear changes are faster with lightened flywheels.