Your 2014 ZX-6R is plenty fast in stock form. It is even faster with just race rubber. It is faster still with a properly tuned suspension. Until you are at the limits of the machine with those two simple mods ...... you are probably the bottle neck, not the bike.
It is your money, and you can do with it what you want, but you should be better served by spending it on 1) fees to actually get on the track (track day, practice, race, etc.), 2) tires, and 3) suspension.
Money can be spent all kinds of different ways that do not make you faster. A few examples are paint jobs, shiny things, carbon things, engine mods, exhaust pipes.
I highly suggest getting on the track ....... road racing is still THE MOST EXCITING thing that I have done so far in life.
I'm not doing the mods to gain me a competitive edge on the track, whether it's racing or a track day. It's more for just.. Me.. On the street. I have a *knack* I guess for wanting to do unlock some power on my bike that's been held back. Seems like every bike out there has all of these aftermarket parts for those bikes, including internal parts, like Pistons, rockers, valve springs, Injectors, Cams, aftermarket heads, aftermarket titanium headers (just the header, not the full kit,) Veramic bearings for the Transmission, etc... There are no parts like these for the 2013+ bike, except ceramic bearings.. I can get my 2 stock cams regrinded, but that's more of a service, not a product.
And the Stage 3 REGRIND requires no available High Compression Pistons, No Available High Performance Valves & Valve Springs....
My bike has always been the fastest "600" while out riding with friends around town, but there are new bikes out that have upped their game like the R6.. Motor is the same, but everything else has been changed & its faster.
I'm just wanting to achieve 135-140rwhp RELIABLY. While doing my first set of track days, I'll probably put my bike in "B" Mode anyway with retarded timing & just 91 octane fuel.
Just got a little bored with how quock it is and im not in the position yet to buy my 2020 Aprilia. RSV4 1100 Factory, yet.
So just came, customs of I can find them, connecting rods if I can find them (because they are the weak part of this engine,) my .50" Kawasaki Racing Thin Head Gasket to raise my stock compression from 12.8:1 to 14.0:1.
Then Port & Polish my heads
And Stage II or Stage III Web Cam REGRIND. (!500 difference + HP valve springs, valves, hi comp Pistons (I still need to ask them if my thin head gasket will suffice or if they have one for me.)
That's all. Just a few small things. Nothing bottom end, although I'd love to lighten the entire crankshaft & maybe even finding a striker one that will striroker it to like, a 650 so when i race other Ninja 650's, I'd blow them away. Hiding the extra 2 cylinders off the header pipe behind an R&G Racing Radiator Cover lol
Anyway. Who knows if I'll do anything more than my Yhin Head Gasket & a Stage 1 Porting of my heads, maybe a Stage 1 of Polishing if I have the right tools to do that..
I'm about done with this bike. I need to get a set of Armour Bodies, Pirelli SuperCorsa SP's, track suit, SIDI Boots & I like my current gloves & AGV Corsa "Italy" helmet, but will have to trade it in for another since its getting past its 5 year life. Wish someone would restore these $1000 - $1800 helmets & recertified them. Bought it in Mid 2015. Rode then, rode in 2016, haven't risen in 2017, 2018 & not in 2019. Getting back on in 2020 for sure. So I only have a year & a half, maybe 2 1/2 years max & now my perfectly conditioned helmet with 3500 miles on it, can no longer be used at the track. I'll keep it as my street helmet until i feel that those 5 years of usage has added up.
So.. I'm still waiting in the price of the AGV Pista GP-R Valentino Rossi Tribute to Nicky Hayden Helmet comes down in price.. Sticking highest helmet they have @ $1899