I'd bet there's another tenth in Ti valves, even at your speed. You can run a good valvetrain on steel seats with CRN treated valves. I wouldn't run any steeper than a 52* seat to avoid 'sticking' the valves. Somewhere around 2015 on March 4th a wiseman once said:
(1) Can you turn a steel 2.300 to 8000rpn, Sure you can BUT, Your missing about 60hp, beating the hell out of your valve train, beating the hell out of your seats and knocking down your springs 5 times faster. Just because you can do it doesn't mean its mechanically sound " getting away with it" does not make it the proper way to do it.

(2) If you operate your engine over 7500rpm use Ti valves or kill 30hp. Thats the rule. Violate it with any excuse you chose to use but that's what our testing has proven.

We have done this test so many times with so many cams I lost count. (cams listed in our cam list on our web site) so here it is.

If you routinely operate your engine ABOVE 7500rpm use Titanium valves. If you operate your engine to 7000-7500rpm then you can use steel valves BUT, Ti valve will still make more power in this range. Titanium valves are worth anywhere from 30hp above 7000rpm. I see it in 90% of other engines as well I just wanted to clarify that all the testing here is done with our cams. There is always someone who claims they dont use Ti valves and run just FINE to 8000rpm. FINE compared to to what? Titanium valves control the valve train which triples your spring and component life if you operate to 8000rpm.

My rule is this. If you operate above 7500rpm, Ti valve are mandatory!