Cylinder packing plates

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Boreham
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Does anyone have an 'idiots guide' to the advantages/ reasoning for fitting the packing plate at the base of the cylinder or at the head?
I am looking at a 60mm crank on a pinasco 177 kit, understood the need for the 1.5mm packer but on checking the options there is the std thicker base plate or a thicker head gasket (or even the MMW head machined for no additional head gasket)
Thoughts appreciated.
ducksta
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put the kit together without the packer and see where the piston is compared to the ports then you will know either base or head
live life your a long time dead
GLscoot
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I was told you also need to do a squish test, three strands of solder wire in a pyramid shape spanning the full diameter of the piston, turn the piston over by hand without the plug in. I think this is to make sure that the piston does not hit the cylinder head. I had a 1.5mm spacer on first then barrel and just to make sure i used a cardboard spacer 0.25mm between the head and barrel, but to be honest this is my first go at tuning a engine. Managed to port the casings myself to the Polini 180 kit, fairly easy job. In the winter I will port the carburettor. I hope this helps.
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guygrrr
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Essentially, packing the cylinder will give power at higer rpm's, loosening up a few more horses. where as packing the head allows power at lower rpm's giving more torque and better acceleration.
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more can do, less doodoo.
Boreham
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Cheers Guy, that was the info i needed, torquey tourer = thicker cylinder head gasket!
Norrie Bodge
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Another option also...
Try a 1mm base packer & 0.5mm head gasket.
1.5 - 2mm on head squish
Keeps it torquey & regains a decent top-end too :-)
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