Generation IV External Engine - How high can i rev this engine??

I have this katech engine that is for my race car, and i want to know how high i can rev it? and maybe what i can expect from running it on e85 with a good tune.

And if 6400 is the absolut max, then what mods do i need to rev it higher.
I am running a Mid valley 4 speed gearbox.

CR: Unchanged from stock. LS2 should be about 10.7:1
Injector size: Stock LS2
Cam: 227/235 @ .050, .361/.365 lobe lift, 113LSA, 1.7:1RAR
RPM limit: 6400
Power: 509@ 6600, TQ: 447 @ 5200 (actual, not estimated)

-Street camshaft, mild lope
-PSI springs
-Trend pushrods
-CNC-ported heads
-C5-R timing chain
-Katech oil pump
-Katech aluminum valve covers, powdercoated red with Katech logo inserts
-Katech coil relocation kit with black wires
-Katech billet belt tensioner

Specs:
58x/4x triggers
90mm edelbrock trottlebody
Corvette damper/water pump
Corvette oil pan

best regards
Joachim

I would say 6600-6800. Any higher and you're going to need some rod bolts, which should get you to like 7000-7200.

But I wouldn't push it past 6800 with that cam.

You dont need anymore rpm than your making power at anyway but if you exceed 6500 and blip it to say 6700 it isnt going to all of a sudden let go... it will be accumulative damage I would think that will break things

With a 228 228 113 cam I use to rev our old LS1 to 6,950rpm.
Our new LS3 only buzzes to 6,800 on gear changes with the limiter set t 6,900.