Harmonic Balancer Rb20det & Rb25det

[zertek]

Hey guys, in the middle of a conversion, RB25det upgrade from my RB20det. The RB25det harmonic balancer has 2 decent cracks around the front rim, which im sure will tear what ever belt i put on in half. So looking at my RB20det balancer (with no cracks)... they are slightly different but the over all 7 timing marks are visually the same.... just checking if these are ok to swap?

RB20det balancer

RB25det balancer

timing marks (visually identicle on both)

thanks!

[VHR32]

There is a difference.

I rang Ross and spoke to them about their Tuffbond balancers and they told me the differences between RB20,25,26,30.

But I cant remember sorry!

[AD4M]

only diference is the number of ribs for the power steering belt

rb20 and rb26 from r32's run a larger belt for the power steering and hicas pump (pumps from front and back)

rb25 and rb26 from 33/34 run one less rib on the belt becuase the hicas is elcetric so less stress/load on the power steering pump

so no you cant run an rb25 ballance unless you run an rb25 power steering pump and remove the hicas (this is what i have done)

[skybarge]

Yeah i second what AD4M says

Get rid of your old dual stage power steering and hicas, get an R33 Single stage pump(half the size of R32), bolt straight on and use an R33 belt

[zertek]

ok... well i know that the timing belts are the same for the rb20det and the rb25det and the timing marks are the same on the balancers.... im guessing its ok to just do a direct balancer swap (use rb20det harmonic balancer on rb25det).

I will be using the R32 power steering pump and air compressor still because i have left them attatched to the engine bay and ready to be bolted to the rb25det when its dropped in... meaning i wouldnt have to change any belts either (Rb20det power steering pump and rb20det balancer).

Tomorrow i will measure the balancer sizes and post up results, just for reference if anyone else needs to do the same.

Cheers

Edited July 27, 2007 by zertek