the pistons are supposed to be 9:1 CR, but will be more like 8:1 by the time i'm finished with everything hopefully
right, tonight i've been back to work to machine my billet main caps. we came up with an ingenious way of boring them on our cylinder boring bar... we do have a line borer, but it was deemed easier on the boring bar
first we had to check that the block was sitting true on the machine, so i bolted the old main caps on, then set the guage to check we were central on the ID. ui then moved the guage down into the other mains to check taht they were also straight and true. with a bit of fine adjustment, it was spot on
all set up:
we then had the dilemma that we'd never bored steel before... only ally or iron, so we had to set the machine to take small cuts off at a time, with a slow feed speed and high spindle speed, to try and keep it from smashing a tip, or moving the block. we got it sorted and set it going:
Smokin'
. We then made the cuts bigger and bigger until we were 2 thou under final size.
onto the next machine... the line honer! this makes sure that the caps are completely true and all honed to the correct final size.
here's a pic of the machine:
after a few licks with the hone, and a bit of measuring, this was the end result:
Spot on
. hopefully i'll be able to bore and face the block tomorrow (all done on the boring bar i used on this). i hope this has helped some people understand what these jobs entail, as i know everyone on here isn't an engineer or mechanic. i'll hopefully be doing some more step-by-step guides as i do more machining
let me know what you think