440 main bearing housing diameter

[Cato Vinther]

Hello.

I've got my 440 line bored with new main caps, but i think something is wrong, unfortunately.
Do anybody know what the diameter should be on the main bearing housing, so i can measure that the diameter is correct..

Br Cato Vinther

 

[brian6pac]

2.9425 - 2.9430 Bore size
Hope they didn't f it up

 

[tonysrt]

If it was screwed up a little couldn't oversize bearings make up the difference? It's a thought and a question to the more knowledgeable guys here.

 

[aussiemark]

Oversize bearings are smaller on the inside diameter to compensate for material removed when the crankshaft is ground the outside diameter of the bearing remains the standard size. This size is critical for the correct amount of bearing crush this prevents the bearing from spinning. The ideal way to line bore is to remove most of the metal from the caps and the minimum amount from the block if too much is taken out of the block the timing chain will become too slack. I prefer not to line bore at all unless it is absolutely needed (new steel caps being fitted) if the freshly ground crank spins easily in the block with new bearings and the correct clearance there is no need to do it. I have heard of special timing chains that are made slightly shorter (but same number of links) to compensate. If the bearing bores are not correct you will need to have the cap to block mating surfaces machined and line bore it again.