View Full Version : Stock bore tolerance???

09-23-2009, 09:32 AM
I can find the stock bore basic dimension in my Bentley, but I want to know what the tolerance is? Can anyone help?

I want to make sure that I can simply rehone my 150,000 mile AWM short-block during my rebuild, and don't need to go to an oversized piston.


09-23-2009, 09:43 AM
don't know off the top of my head. There is an out of round tolerance, taper, and bore. Pick up a haynes manual for a passat/a4 from your parts store. I use it for quick references for specs.

If the motor ran well before, then the walls probably just slightly glazed, so you will just need a good bottle brush honing.

09-23-2009, 09:47 AM
haynes manual
lol. He's far better off with a bentley.

09-23-2009, 09:52 AM
I have the Bentley... I just can't seem to find any other detail about the bore tolerances on our motor. My plan is to simply re-hone using a Flex-hone and be on my merry way. But... If for some reason my motor is at the top of the tolerance, then it will change my rebuild plans a bit.

09-23-2009, 11:52 AM

09-23-2009, 11:57 AM
You rock!

Funny thing is my electronic copy of the Bentley, didn't have the diagram for measurement locations, or say the deviation. I wonder if there has been an update since my update elidgability expired.

*Edit: I found the cylinder information in the following section: Pistons and connecting rods, disassembling and assembling.

09-23-2009, 01:30 PM
lol. He's far better off with a bentley.

hes far better off because the specs are the same? brilliant

10-12-2009, 06:15 AM
So.. when it says 0.08mm deviation. Does that strictly refer to the bore tolerance? Also, does that mean Bore X +/- .04mm for a total of .08mm tolerance. Or does that mean Bore X +/- 0.08mm for a total of 0.16mm tolerance? 0.16mm seems really big!