Crank pulleys - RB20/25/26

[Zacho]

Here are some pics to show the differences between the pulleys, so you can decided if interchanging is right for your setup.

http://images.quickblogcast.com/9/3/5/3/1/121610-113539/balancercom.jpg

http://images.quickblogcast.com/9/3/5/3/1/121610-113539/harm2.jpg

http://images.quickblogcast.com/9/3/5/3/1/121610-113539/harm4.jpg

http://images.quickblogcast.com/9/3/5/3/1/121610-113539/harm3.jpg

[mcfly]

they need one rb20 vs rb26, looks like they would interchange.

[DrMango]

it looks very close in depth anyways. Why would someone want to interchange a pully though, is there a real benifit?

Kyle

[Zacho]

it looks very close in depth anyways. Why would someone want to interchange a pully though, is there a real benifit?

Kyle

Not so much looking for a benefit, but a replacement. I had a bitch of a time finding a decent RB25 one. If I was in a pinch I would have got an rb20 pulley.

I had the one of the RB26 vs. Rb20 but can't find it. I'll look later for it again.

[Snow]

it looks very close in depth anyways. Why would someone want to interchange a pully though, is there a real benifit?

Kyle

Wouldn't there be benefit in the RB20 pulley being put on an RB26? The smaller pulley would reduce load on the crank freeing some rotating power would it not?

The only problem is that this would in-turn spin the pulleys on your accessories (power steering, alternator, AC, water pump etc.) slower which could also run you into other issues.

[DrMango]

I agree SNOW, I think that it would affect the accesories so it wouldnt be an advantage to do so

Kyle

[TougeJunkie]

Well it should act like having a set of underdrive pulleys, some people underdrive their pulley set up because at higher RPMs water pumps can suffer from hydrodynamic cavitation that is very hard on the water pump and will lead to a failure, also there is no benifit in rotating an alternator or PS pump past the mid RPM range anyway because thats where their mechanical performance peaks

[DrMango]

So it could be a good thing to have a RB20 pulley on an RB26?

Kyle

[Snow]

So it could be a good thing to have a RB20 pulley on an RB26?

Kyle

Or an underdrive pulley set for the alternator and power steering, possibly water pump if you do a lot of high rpm driving (ie a drift machine where cooling is essential).

I was looking for an underdrive pulley set. I found some here:

http://shop.rawbrokerage.com/RAW-RB-CNC-Pulley-Set-raw-cnc-rbpulleyset.htm

http://shop.rawbrokerage.com/Ross-Metal-Jacket-RB20DET-Harmonic-Balancer-306200.htm

I don't drift per se but would like to reap the benefits of less drag on the crank. It could be a worth while investment. If your alternator is dying though, you can imagine you would be replacing it quick. You could also get a more efficient alternator, or have a more capable one rebuilt out of your core if you run into issues...

[DrMango]

Good info guys. Thanks

Kyle

[mcfly]

I noticed mercedes uses alternators of 180 amp and up. a lot of them are in the 220 amp range now.

here we are using 80 and 90 amp alternators still, i feel like a dinosaur.

[TougeJunkie]

True, if we had electric every thing we would need a 220 as well, Im glad we dont have all that stuff .... bare bones for me , I dont even have a stereo

[DrMango]

True, if we had electric every thing we would need a 220 as well, Im glad we dont have all that stuff .... bare bones for me , I dont even have a stereo


I agree. I don't even have a stereo either. Most everything from my car has been stripped. Im happy with the 90. Probably doesnt need to use as much of the engine power to spin the alt too right?

Kyle

[Snow]

I agree. I don't even have a stereo either. Most everything from my car has been stripped. Im happy with the 90. Probably doesnt need to use as much of the engine power to spin the alt too right?

Kyle

Technology is a beautiful thing. I would imagine it would require more draw, but at the same time it would be created much more efficiently.

I'm sure if you compared a modern day 90Amp alternator to one of ours out of our cars it would be far more efficient...

[mcfly]

the 220 amp alternator that you see on a benz is more compact then our 90 amp.

[DrMango]

the 220 amp alternator that you see on a benz is more compact then our 90 amp.

WOW thats pretty cool but it wouldn't fit without heavy mods I bet?

Kyle

[DrMango]

OOPS

Kyle