This is my new crank(A15) i'l be trying out soon. You can also see the balancing. Milled and knife Edged.

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this kind of modification applies only for race purposes or can it be used for daily driven too???

any advantage or disadvantage of doing this kind of mod??

thanx..

Aside from making all the counterweights as much the same as possible, do you have any other tips for someone who plans to embark on this challenge Gary?
I have most of the bits to build a turbo A14, and I'm now leaning towards knife edging the crankshaft. (I've got a bet with a mate who is also building one, and I want an edge over him)

This is going into my street ute... haha.

Here is my crankshaft.






Try use a crankshaft that has fewer (drilled) sections removed from the counterweight lobes. These create some drag/resistance along the knifed edge which won't help with the knife edge effect.

Also, try getting a hold of a scalloped A14 crankshaft (assuming your K-edging an A14 crank)these are lighter already and may save on costs. The counterweight Lobe is also located further out making it easier to work on.

Boyz...I just spent the last two hours creating a post on the intricate machining of doing a knife edge, only to have the internet crash as I was proof reading, sorry I'm F***ed off and over it!

you can use it for a street engine.

It really helps at higher RPMs like 10,000 RPM since it is more aerodynamic.

thanks.. dd..

Quote:

Things that wake you up at 2am....
Heres something to think about for those who like to think about things.

As some of you will remember I have had an issue with wearing out camshafts and lifters, I think I might know why now, it's a theory anyway.

Going through the oil galleries layout in an A-series I was thinking how a camshaft lobe actually gets lubricated, my thoughts are that a small amount will leak down from the head into the lifter gallery and drain past the lifter, a very small amount i think.

The other ways are seepage past the main bearings and the big end bearings and then it is flung onto the camshaft lobe off the crank, if you have a look at the picture of my bottom end a couple of pages back you will see that each cam lobe is inline with each counterweight of the crank, as I have done is remove the area of the counterweight and made it less area for oil sling to hit the camshaft.

Im thinking that this might be why I am wearing out camshafts because not enough oil is hitting the cam. I have spoken to a lot of people about this issue (reputable engine builders, oil companies) and we all agree my problem is oil related.

Even with splash coming up from the wet sump I don't think it's enough to get up to the camshaft area and lubricate it.

Personally I think this makes alot of sence, I have designed and modified a crank not to hold oil on it.