Showing posts with label FW Thornton. Show all posts
Showing posts with label FW Thornton. Show all posts

Friday, 16 August 2013

Rings...


So the block is now ready to go on - it's time to gap the rings and fit them to the pistons.

I bought my rings from FW Thornton after asking both them and JP in Australia to quote. I had asked Drags as well, but the GPM rings they supply require the ring grooves to be machined to depth - and wisdom from the AOMCC forum suggests this is not easy.

So, having a modicum of engineering knowledge and some measuring tools, I read up on rings & piston design courtesy of Mr. P Irving's writings and set about sourcing the rings from basic dimensions. Duncan Rowley (who is a very helpful chap) at Thornton's came up with this set of rings from my dimensions:


We have our rectangular top rings:


And our Napier pattern second rings (this one is upside down):


And the oil control rings:


Speaking of which, don't forget to clean out these holes:


These are there to clear the oil which the oil control rings scrape off and return it to the sump.