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I am trying to set up a rb26 head with new springs and cams.

Cams are Cam Tech Cams and specs are

post-40332-0-44007200-1371712744_thumb.jpg

The springs are performance spings and specs are

post-40332-0-94613600-1371712775_thumb.jpg

And my current install heights are

post-40332-0-36852700-1371712761_thumb.jpg

So does adding (coil bind+ cam lift+ 60th spring clearance) = correct install height

so ( .936 + .424 + .060= 1.42) 1.42 does this mean this is my correct install height

If 1.42 is the height i need my springs at WTF do i need to do to get my values from 1.5** to 1.42

There is a .040 shim under the springs now. Do I use more shims to get the correct height and where do i get these shims from

different install heights give different seat pressure, the second pic gives values

@ 1.520" = 67 psi seat pressure - closed valve

@ 1.130" = 166 psi seat pressure - open valve

you have a range of install heights all around the 1.510"-1.530" which give a seat pressure of around 67 psi

coil bind is @ 0.936" which is the limit of how far you can compress the spring

if the 3rd pic is what you have them installed at then reducing the install height will increase seat pressure depending on how much pressure you want but the lower the install height the less lift the cams can have

different install heights give different seat pressure, the second pic gives values

@ 1.520" = 67 psi seat pressure - closed valve

@ 1.130" = 166 psi seat pressure - open valve

you have a range of install heights all around the 1.510"-1.530" which give a seat pressure of around 67 psi

coil bind is @ 0.936" which is the limit of how far you can compress the spring

if the 3rd pic is what you have them installed at then reducing the install height will increase seat pressure depending on how much pressure you want but the lower the install height the less lift the cams can have

so by calculating .936+.424+.060=1.42 witch is coil bind+cam lift+ .060 clearance befor coil bind = 1.42

Would this 1.42 be my correct install height or is that formular incorrect

formular seems correct, the recommended install height would be 1.52", as per spec chart, 1.42" would be your limit so any where between the two would be fine depending on how much seat pressure you want

if you go 1.42" then you won't be able to put higher lift cams in later with out reseating the springs, 0.1" is 2.5mm difference

67psi is not bad, I have my BCs set at 85-90psi

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