APE heavy duty valve springs.

[paolo0045]

hi have bought a set  heavy duty  valve springs for suzuki GSXR1100 1991 oil cooled M N APE heavy duty  valve springs.

need info how do i check for 40 lbs seat pressure height when the springs are new what do they mean

[Gixer1460]

Fit a couple of complete valve assemblies ie. std spring seat, valve, springs, spring retainer and collets + additional 0.06" shim under the std. spring seat. Then measure the height of the spring between the spring seat and underside of the spring retainer - this is the 'installed height' - lets say its 2" or 50mm!

Disassemble and grab a spring tester, clamp the spring to be tested on the tester and compress to the installed height ie 2" or 50mm and read off poundage achieved!

Most people don't bother unless its a high value / high rpm racing engine as to be truly accurate the spring seats in the head should be all milled to the same height before measuring the installed heights, then measure the spring pressures, then adjust the added 0.060" shim thickness to add or subtract spring pressure. As said a complete faff done 16 times ! ! !