Just obtained a spare set of Evo IX cams and am going to have material added and reground by BrianCrower to the specs of their street cams. But I was wondering if installation of springs and retainers would be absolutely necessary to avoid valve float at high RPMs or can I keep the stock ones and be okay?

Here's the link to their page/cams if it helps:http://www.briancrower.com/makes/mit...g63_evo9.shtml

 

Depends what you call high rpm, should be good below 7k

 

Yea by high rpm I mean stock redline(7k)...Thanks for the input, I'll probably just build the head while I'm installing cams, might as well so I don't have to take it apart again for a while.

 

I spin my stock 9 springs/retainers to 8K with Kelford 272s, so you should be fine to 8K , I would think.

 

Okay cool, that calms me down knowing youre running about the same on stock springs/retainers and able to spin to 8k.