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GSF /GSXR engine cases Big Block without dry-blocking possible 85mm pistons ?


FJD

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good evening, is it possible to run the bigger cylinder sleeves with big block (outside diameter 89mm) without getting in the oil gallery on top engine cases ?

I know it can be done with the the smaller liners (OD approx 87,1 mm).

Looks really tight to me, oil holes are 4mm and at an angle so probably interfere with sleeve cutout.

Is it possible to shave off some meat on the #1 und #4 sleeve outside to clear ?

Any hints and infos ?

Also: what is the angle of the cylinder relative to gasket mating surface between upper/lower half ?

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11 hours ago, FJD said:

good evening, is it possible to run the bigger cylinder sleeves with big block (outside diameter 89mm) without getting in the oil gallery on top engine cases ?

I know it can be done with the the smaller liners (OD approx 87,1 mm).

Looks really tight to me, oil holes are 4mm and at an angle so probably interfere with sleeve cutout.

Is it possible to shave off some meat on the #1 und #4 sleeve outside to clear ?

Any hints and infos ?

Also: what is the angle of the cylinder relative to gasket mating surface between upper/lower half ?

See my answer elsewhere to your other post. But confused re, last sentence? The cylinders / block should be bored perpendicular ie. 90 degrees to the crankshaft so why would anyone want to make that operation more difficult by having the gasket mating surface in a different plane. Reference surfaces of top of crankcase, bottom and top of block, underside and top of cylinder head are ALL usually parallel to crankshaft axis. I have seen on different engines, the underside of the cylinder head faced at an angle as a tuning mod to increase combustion / change valve angles / squish etc., but generally in most cases all are parallel.

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No, that was not my question, the cylinder base gasket (and head gasket etc) surface is inclined to the horizontal engine mating surface between top and bottom engine half.

Will have to measure this, and adjust milling machine table, to be able to bore vertically towards the crankshaft.

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Ok, gotcha now! But knowing the angle doesn't really help, as, supposing its 10 deg, what are you using to a) measure that and then b) set the machine up at that angle? You are working against tolerances and inaccuracies which could stack up and end up +/- 0.25 degree which the gaskets won't take up? (probably worst case but you get the drift) Its easier to clamp the case using a sized bar through the bearing journals, then sweep a test indicator across the gasket surface to achieve flat and perpendicular to the boring bar & the table. You shouldn't adjust the machine to the part, adjust the part to the machine IMO.

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