S6 block /crankshaft info.
Discussion
A little info for any other S6 builders!
Dulford are building up 2 S6's at present, both (early) blocks have now needed line-boring to allow crank to run true in bearings, when precisely measured with cut-out straight edge & dial guages.
It's a long crank. Mine was 6thou out end to end, so once running for a little while was already scuffing some bearings. Good thing the builder was able to spot the slight signs, as it turned over quite freely before being fired up.
Not saying that all others would be the same, but any that were would wear the main bearings oval prematurely, eventually leading to other bearing or crank issues. So worth a full check if anyone's having a re-build of an early block.
YI8TVR said:
Thanks Paul, I will pass that on to Mr Beardy.
Wouldn't an engine builder worth his salt check the alignment as a standard procedure though Paul.
Wouldn't an engine builder worth his salt check the alignment as a standard procedure though Paul.
if a block is being machined for you... these blocks were 3rd-party supplied allegedly fully machined to top spec for this builder to use 
However, to check it to such a fine tolerance is not easy, you need a perfect straight-edge with cut-outs made up to suit. You'd think any top builder will do it, but worth checking.
I had to scrap my block and crank because of something like this. Paul, you have a Craft engine if I remember correctly? Have you checked the state of your followers? I ask because I know the coating on the Craft sourced followers has flaked off on most of their rebuilds. I've ditched everything they sourced apart from the pistons and rods because I just couldn't trust any of it. A very expensive mistake. All is well now though as I'm in the professional hands of JC at STR86 with a new 2006 block based engine. Just waiting on these damn Nitrons which seem to be delayed forever!
Al.
Al.
tail slide said:
A little info for any other S6 builders!
Dulford are building up 2 S6's at present, both (early) blocks have now needed line-boring to allow crank to run true in bearings, when precisely measured with cut-out straight edge & dial guages.
It's a long crank. Mine was 6thou out end to end, so once running for a little while was already scuffing some bearings. Good thing the builder was able to spot the slight signs, as it turned over quite freely before being fired up.
Not saying that all others would be the same, but any that were would wear the main bearings oval prematurely, eventually leading to other bearing or crank issues. So worth a full check if anyone's having a re-build of an early block.
On the blueprinted option which I did'nt have the cross drilled 92mm stroke cast crankshaft is checked for size to a tighter tolerance, bearing surfaces polished to a higher standard and balancing to within 2 grams.
Richard showed me 2 speed 6 rebuilds that he was currently doing when I was down there last month. Might have been yours then.
S6SFX - glad to hear you're nearly sorted after so many traumas, we'll check the AC followers.
Icraigmy - yes one would have been mine. To clarify, it was the main bearing carriers in the block that were very slightly out thereby needing more machining of the block, the billet crank was spot on.
Hopefully you've been able to open yours up and have some fun by now?
Icraigmy - yes one would have been mine. To clarify, it was the main bearing carriers in the block that were very slightly out thereby needing more machining of the block, the billet crank was spot on.
Hopefully you've been able to open yours up and have some fun by now?
tail slide said:
S6SFX - glad to hear you're nearly sorted after so many traumas, we'll check the AC followers.
Icraigmy - yes one would have been mine. To clarify, it was the main bearing carriers in the block that were very slightly out thereby needing more machining of the block, the billet crank was spot on.
Hopefully you've been able to open yours up and have some fun by now?
Icraigmy - yes one would have been mine. To clarify, it was the main bearing carriers in the block that were very slightly out thereby needing more machining of the block, the billet crank was spot on.
Hopefully you've been able to open yours up and have some fun by now?
It's awesome
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