Lightweight pulley experiment.

[rev210]

I'm prepeared to get a lightweight front pulley made for the Rb26dett. At present I have a post on the forced induction area.

I have the oppertunity to have a front pulley made when a mate gets a few RB26 engines in a few months but, I was wondering if anyone has a spare front crankshaft pulley lying around they would be willing to lend me so I can have a copy made in alloy. This would save me waiting around and mean the 'test' will begin earlier and provide WA Rb26 owners with an earlier oppertunity to get cheap pulleys should it work.

[ix9]

Saving maybe 500g on a pulley? Isn't that a bit of reach in terms of power/response gains rev?

[rev210]

The factory unit weighs about 6kg. An alloy unit can be made around 800gms, thats a saving in the order of a light flywheel with the same effect.

There is a possibillity of making a unit with a vulcanised rubber sleave just like the factory one however instead of steel it can be made of alloy. I'm guessing the weight would be around 1.5kg. This type of setup would probably cost two or three times as much to make. I would need to pull the factory one appart, have the alloy machined to the same dimensions and have a vlucanised rubber sleave bonded with it.

[ReVN211]

my old man could spin you one up he's a fitter and turner and makes pullys all the time!

[rev210]

Champion ReVN211 !

Once I get a pulley we can start the experiment. Sooner if someone can offer an RB26 crank pulley to copy.

[BoOsTeD_RB26]

I have one this way as well as a rooted crank. PM me details.

[ix9]

Interesting theory.... let us all know how you go...

as well as how much it all up costs.. might be another "rev210 special" mod to get that mystical 12sec pass!

[RB20LagWagon]

Yeah but actually pull a 12 this time

[N I B]

Will be the same disaster as the Alloy Z32 ones were with destroyed cranks and bearings

and as ND4SPD had no problems at just over 10000rpm with a stock nissan one id stay safe and use a factory job or tested billet steel ones.

Alloy dampers on the market now for other engines are not alloy copies of factory ones but much larger and no lighter than the stockers.

I've had custom balancers break cranks so violenty that even core plugs have come out of the block from flex.

Race balancers are for the topend of the performance market and wont give any gains worth the time or effort in mild engines so the money would make bigger gains in other areas.

[rev210]

I appreciate where your comming from Steve.

In the performance thread some time ago we covered the argument about the RB series being of the NVH style of pulley or an actual harmonic balancer. I am placing a bet that it is a NVH because so far no one has given any data or examples of it not being one. It's certainly not a 'rock solid' position but one I am willing to test due to the fact there is great benifit to be had if I am on the right track. I don't mind putting a well worn motor to the test because due to the pre-existing wear any harmonic issues will show up straight away. That and I think 230,000kms is pretty good out of an Rb26 and if it needs a rebuild I guess it deserves one

http://www.skylinesaustralia.com/forums/sh...ighlight=pulley

Thanks all the same for the input I'm quite glad for it. It's good to have people looking out for you trying to save some heart ache.

So far I have a pulley offered to measure up and a place to get it done. I'm interstate for the next two weeks so when I'm back I'll start to the ball rolling for the test.

[NO_RSPECT]

good luck...its time we joined the sr20 and ej20 crowd