Beg, borrow or steal a micrometer from somewhere, and check all your crank journels for ovality etc.

I just had to completely rebuild my A14 again because no 4 Big end oil gallary blocked and stopped oil getting to the rod.

Im not that technical but ill explain to the best of my ability what was wrong with my car.

My father is a mechanic so after closer examination why only no.4 big end bearing clogged and not any others, dad found that there is a oil line (or something like that) iside the crank that goes from the mains to the big ends and that was clogged full of stuff in there.

now that i have cleaned that out we know its all working and car is running like a dream.
This is also after replacing all the bearings, big ends and mains, new timing chain, fixed the conrod and shaved the crank. oh while i did all that i took my cam shaft down to the shop and had it ground out to 35/70 (sounds pretty lumpy now)

Before we had cleaned this out, i had done my big ends twice in the past 4 months because the big end bearings went.

Yeah the oil issue I will come across when I take the crank out completely. I would say it would have muck in it and this is why it wasn't oiling properly.

I have also found that the cheap torque wrench I was using was terribly inaccurate so I'm angry with that. SO this explains why it was so tight when I first started it up.

The knocking is a worry though. It was almost as if the cranks shafts (where the conrods bolt to) have been machined down. Although I am certain the previous bearings are excactly the same thickness.

It has to be the gudgeon pins, but it's very rare to have all four wear out in the one instance.

This is so strange.

I will strip the block, clean the crank double check all clearances ensure the bearings are okay and hopefully then there will be some positive results.

It would just be so helpful if anyone has had the same experience and could shed some light.

There are no short-cuts I suppose.

Thanks to all anyway for the input.