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0.010" deep hardness might be the suitation for case hardening, but camshafts are induction hardened, cams can actually end up harder after a regrind. If it has 8 or 12 lumps on it when you pull it out, it can be reground to make a healthy D grind.(To make a bigger cam you take the meat away from the base circle, so weenie A grinds & reasonable C grind cams can end up looking as good as a new D) Ford & Holden cams can't be compared to B20 cams as they are much softer, B20 camshaft & lifters are around 55 on the Rockwell C hardness scale.
"The only way the contact point can be varied is to change the crowned radius on the lifter"
And the only other way is to increase or reduce the taper on the lobe.
And the only other other way is to narrow the lobes to move the centreline of the lobe more forwards or backwards relative to the centreline of lifter bore. :)
I'm guessing these valves are stainless, so don't forget to put bronze guides in on the exhaust. Have you got room to put grooves in for the Volvo collets? There really isn't a need to change away from the rotating valves & they last longer. The last time I used big exhaust valves I started with Ferrea blanks, it end up costing me close to $40/valve. The time before that I used blanks from Repco that were supposed to be one piece stainless but one of them soon became a two-piece valve which punched a nice big hole through my brand new forged Mahles. :/ For a street engine I find it very difficult to use anything but the stock B20E valves as they tend to out last anything stainless. All you need to do is put 4 inserts in so you can run unleaded.
Are you still going to build a stroker like IADR's?
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