Is 90s possible?

Is it realistic to expect that? Probably not.

Is it possible? Definitely 

Go tryout, explain your situation and baseball specific workouts will help. Unless you're at a baseball power of a Juco - 84 will more than likely get you a spot on the roster. 

300ft long toss, no wind, is the ball leaving your hand at 89 mph (minimum).

Sure, you can reach 90.  Probaby with better mechanics. 

It seems reasonable to reach 90 with work. Be prepared with a good explanation why you left the game. It could be a test of what’s inside. 

Very difficult to attempt to answer these questions but here goes...  so a max effort of 86 in high school  means you're sitting 81-84 or 82-85 or lower - most guys with those numbers will never hit 90 consistently if ever (though there are always the exceptions). I would suggest if you want to pitch at your junior college or a D3 that you start working on secondary pitches more than getting a 90 mph FB. Good secondary pitches and a high 80s fastball should be good enough for many JCs and D2 or D3s.  Just 90 velo is definitely not the end all and be all. But hey, if you get there then you have good secondary stuff AND a 90 mph FB. Good luck.

XplosivePancake posted:

So I haven’t picked up a baseball in 2 years and have decided to try to play at a JC. As a junior in hs I topped at 86mph. Got way stronger after I quit. Current maxes: squat 385, bench 245, 15 pull-ups (202 bw), 185 reverse lunge, 375 deadlift. Can long toss up to 300ft. Have been throwing for a few months and got on the mound for the first time yesterday, was at 80-84. Is it realistic to expect to gain another 6+mph? I’m sure my mechanics could use some improvement and I should gain some more arm strength considering my arm was pretty gassed after 10 pitches. I’m 19, 6’1 202 lbs. I know velo isn’t everything, but it’s prob the most important. 

I think you are on the right track with mechanical improvements.  You've got some power in those legs...use them.   "Arm strength" for pitching is kind of a misnomer.   You want your pitching arm to be flexible (like a whip)...try bands and yoga to keep that upper half flexible and core strong.  If this is something you are definitely serious about, I'd find a local experienced pitching coach that can help you get on the right track.    As always, JMO.

Good luck!

Get with a trainer or PC that can assess your movement quality. 

Your strength is good but if you can’t move like an athlete with the lower half,  then it’s not likely.

If you find you don’t move well, train for mobility and connect the pieces........ absolutely it can be done. I’ve seen it done many times.  

I’ve seen gap year guys do some pretty amazing things but you need to find a sense of urgency and the opportunity may not be the most ideal.