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Cylinder spacer aluminum vs steel

turbo RMK

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Feb 24, 2009
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I have a bmp fix kit with steel spacer for axys and also a wiseco fix kit with a aluminum spacer that's going into 09 dragon but have been doing some measuring and the steel spacer is close to .250" but the aluminum spacer is .263 and with both spacers you add second shim so my thoughts would be that shouldn't the spacers be less than .250 with second gasket to bring head to piston squish close to spec not bigger both pistons measure .250 more height from pin thanks
 

richracer1

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Use the specific spacer provided in the specific kits, it has to be those measurements to add the exact clearance for the taller pistons. Also, those aren't spacers, they're gaskets to seal the cylinder bank and the crankcase. The thickness of the gaskets has been factored into to the additional height needed.
 
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turbo RMK

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Well with aluminum spacer and both gaskets with taller pistons with cylinder torqued to spec I'm about 25 thou less squish than was stock so has anyone ever checked specs when installing these spacers and pistons and are they close. Did I just get a spacer that the sheet of aluminum was on the high spec of .250"
 

richracer1

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The only kits I have used were from BMP and MtnTek, both kits had a steel spacer that measured .250", but I never checked the squish.

Give BMP a call and ask them about the squish on their kit.

Who's kit had the aluminum spacer in it.
 

turbo RMK

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Going to call bmp in morning and see what they say I’m I’m starting to think these kits with steel plates are maybe easy and cheap to cut out of quarter inch plate and close enough my steel plate is .253 plus another gasket of over 10 thou called machine shop and they can make me spacer from 6mm which is closer to .240” should get me closer to stock bought kit from dealer was all in nice Wiesco box
 
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