dual valve springs, max. RPM? Options

[SirAndy]

ok, i'd like to get an educated guess as to what my approx. max. RPM would be with a 2056 with heavy duty dual valve springs, solid rocker spacers, 911 swivels, slightly bigger valves, 9:1 compression ...

as far as i can tell, the components used are good quality. i had the rev. limiter set to 6000 rpm which seemed to be on the safe side. only hit the limiter 2 or 3 times during a AX.
always ran plenty of oil, got a tuna can on the motor.
no lean running ...

the motor always felt like it wanted to pull past 6000 and wasn't done with it's peak power yet so i'm thinking there has to be more ...

anyone who can give me a hint as to where the redline could be? ballpark?
(IMG:http://www.914world.com/bbs2/html/emoticons/idea.gif) Andy

[nebreitling]

cam, rods, pushrods?

i've heard mixed things about the dual valve springs -- one engine builder mentioned to me that they are too much for anything but the most built engine... in anycase, they wouldn't be weakest link, i've heard of them going to 7500+.

for my engine (pumped up 2056), i try to keep it at or under 6000 also. but 6200 isn't too uncommon. it sure wants to pull past that...

my uneducated guess would be that 6k on that engine would be quite conservative.

did something happen, andy?