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Peredur
12-04-17, 08:05 AM
I'm going to be fitting big block hubs to my nova to accomodate the larger shafts etc. and I've had the uprights opened out, got the bearings and flanges ready to go.

For the machining of the flanges, is it just the bump on the back of the flange that needs taking down so that it clears the inside of the upright? Or is there more to it?

Thanks in advance

Iain
12-04-17, 11:33 AM
I spent many hours crafting an image that shows exactly what needs modifying on it. It's in the Articles section.

Will F
12-04-17, 11:34 AM
Nope its as easy as that.

Not sure what you mean by having the uprights opened out? Do you mean the hub? If so, you should fit the VW bearing and fit the big block flange as is (no need to machine it down)

Iain
12-04-17, 11:43 AM
The info I gathered at the time I did it was the hub needs machining in various directions to fit well. Good news if you can just smash it straight in.

RallyMarshal
12-04-17, 01:29 PM
Just a question here, but is it feasable to machine the cast hub unit to accept an Astra Mk2 / Mk3 hub and bearing?

Bearing is (ie) Febi Bilstein Wheel Bearing 03271 Width 37,0 mm, Inner Diameter 39,0 mm, Outer Diameter 72,0 mm

New "big block" hubs/drive flange available off the shelf from Febi etc..

Paul..

Iain
12-04-17, 01:42 PM
That's essentially what we end up with (ID and width), except the Audi bearing has a smaller OD so we need to take less material off the knuckle.

Then buy a standard big block hub and tickle a bit off to ensure it fits without interfering with the Nova knuckle. The question is how much do you need to remove from the big block hub.

Peredur
12-04-17, 02:14 PM
Right, to clear things up. I've had the upright (hub) machined out to take the audi whee bearings. What I'm after is, will the astra drive flanges work having only reduced the diameter of the step on the back, or is there more to it?

Iain
12-04-17, 02:44 PM
the upright (hub)

Knuckle.