[Wizard]

Part # Description Duration @ .050" Gross Lift w/1.7
STOCK Stock Turbo Cam 174 / 165 .366" / .343"
HKS264 HKS 264 187 / 186 .392"/.374"
HKS272 HKS 272 195 / 195 .399"/.379"
546/547 Web Cams 206 / 206 .400"/.385"

I also found supposedly the actual spec cards from HKS:

264 Intake
Max Valve Lift - 10.3mm (0.4055")
Centerline at 0mm vavle lift 105 deg
Intake Valve timing at 1mm (0.0394")
Valve opens at 2 deg BTDC
Valve closes at 28 deg ABDC
Valve Centerline 105 deg (WRONG - 103 deg)
264 Exhaust
Max Valve Lift - 9.8mm (0.3858")
Centerline at 0mm vavle lift 117 deg
Exhaust Valve timing at 1mm (0.0394")
Valve opens at 42 deg BBDC
Valve closes at -12 deg ATDC
Valve Centerline 117 deg (CORRECT)

272 Intake
Max Valve Lift - 10.3mm (0.4055")
Centerline at 0mm vavle lift 105 deg
Intake Valve timing at 1mm (0.0394")
Valve opens at 6 deg BTDC
Valve closes at 32 deg ABDC
Valve Centerline 105 deg (WRONG - 103 deg)
272 Exhaust
Max Valve Lift - 9.8mm (0.3858")
Centerline at 0mm vavle lift 111 deg
Exhaust Valve timing at 1mm (0.0394")
Valve opens at 36 deg BBDC
Vavle closes at 2 deg ATDC
Vavle Centerline 111 deg (WRONG - 107 deg)

I cant find any stock valve spring coil bind limit, but guessing it would be around .450". And it would be a nice safe bet the the measly $200 on a basic upgrade springs/retainers would give you insurance. Not to mention, the stock springs are not new and their numbers have surely faded over time. IE: Weaker and more prone to break or bind. Bad time find to this out is after you put your multi$$$k motor together and first good pull over 6k and a valve fails to close in time.

Just upgrade and you'll be safe.

Wiz