Crank Collar Affecting Balancing?

[JustinP]

I have had everything fully balanced (RB25DET Neo) from the harmonic balancer to the clutch. The crank does not have a crank collar.

If I was to get the crank machined to take a crank collar, and the collar installed, would this significantly affect the overall balancing to warrant a full rebalancing of everything?

I do want it to be REALLY well balanced and smooth. My dad is a big BMW / straight 6 fan, and he is always going on about how well balanced they are from the factory. I'll show him!!!

[BMYHOE]

probly best to talk to a machine shop or wait for Greg R31 to reply as he does this everyday

[The Dan]

As long as a competent machine shop has done the balancing then no it will not matter. The weight of the crankshaft compared to the weight of the collar is something like 100:1.

The flats are opposite and the outside diameter of the collar is so close to the centre axis that it would not be able to be measured accurately by any conventional small/medium engineer ( I say this because technically everything can be measured but how much do you want to pay )

Short answer: Hurry up and get your engine to skid status

[JustinP]

Thats what I was thinking, thanks for the reply

And yes, I'm going to get my ass into gear and get this thing finished!

As long as a competent machine shop has done the balancing then no it will not matter. The weight of the crankshaft compared to the weight of the collar is something like 100:1.

The flats are opposite and the outside diameter of the collar is so close to the centre axis that it would not be able to be measured accurately by any conventional small/medium engineer ( I say this because technically everything can be measured but how much do you want to pay )

Short answer: Hurry up and get your engine to skid status

[Gerg_R31]

As long as a competent machine shop has done the balancing then no it will not matter. The weight of the crankshaft compared to the weight of the collar is something like 100:1.

The flats are opposite and the outside diameter of the collar is so close to the centre axis that it would not be able to be measured accurately by any conventional small/medium engineer ( I say this because technically everything can be measured but how much do you want to pay )

Short answer: Hurry up and get your engine to skid status

what he said