Quick noob question about my 1990 rx7 GXL
 

My shift knob vibrates a fair amount while I'm driving. Also the boot gets pretty hot, is this normal for these types of cars? The car only has 93k miles if that matters. This is my first rotary and I like it alot

Look into shifter bushing from Mazdatrix.
You can toss some dynamat or insulation around the shifter( Like I did) and it stops the heat from coming up around the shifter.,I did it with a spare piece of the rear deck insulation/rubber matting.

What do you mean by "around the shifter" do I need to open it up? And any particular products you'll recommend

Read here:
Mazdatrix FAQ - 86-92 Shifter Bushings

Also, synthetic transmission oil will help reduce some of the 'notchy' feeling. I like Red Line MT-90, but other brands like Royal Purple and Amsoil will also work well.

Hey you're from STL too! anyway, the guy I bought it from said to never use Synthetic on this car since it's been using 10W-30 Castrol GTX since its purchase

He was talking in the trans, not the motor

10w-30 is a little thin, should be 20w-50

This forum started in STL.

The synthetic engine oil restriction is from decades ago when some synthetic oils were substandard so Mazda made a policy not to use synthetic oil in rotary engines (and at the same time their race teams were winning Le Mans with synthetic engine oil, lol). Also, there is an urban myth that swapping back and forth between synthetic and non-synthetic will cause leaks, nuclear explosions, world famine, and (gasp!) another Miley Cyrus album, but this is not true. You can use modern synthetic oil in the engine but in my opinion it is a waste of money for a street car that does not experience harsh conditions. The transmission, on the other hand, usually shifts noticeably better with synthetic oil, and it has a very long change interval so the pricing is not such a big deal. I haven't found a good place to buy synthetic transmission oil locally, so I just order online from Jegs, Summit Racing, Racer Parts Wholesale, or Pegasus, whichever has the best pricing at the time.

I use 10W-40 engine oil in St. Louis, which is the best grade for street driving and autocross year-round in our weather. 10W-30 is a little on the thin side. I use 20W-50 in hotter climates like Florida, but this would cause engine wear and slow starting in the cold STL winter. My personal opinion is that Castrol GTX works best, and that is based on input from my engine builders who have commented on the reduced wear and cleanliness of rotary engines that they have rebuilt. Also, in the radiator be sure to use distilled water rather than tap water if you mix the coolant yourself. You can usually buy it at Walgreens or CVS, although some store locations don't have it.

Pop the carpet up at the back on the rear hatch floor of the car..look at what the mat/rubber/insulation material is there..
That stuff.
And all you do is grab the shifter surround and boot,put a screwdriver on the crease( inbetween the shifter surround and the console) and Pop the surround up to get at the Shifter..It's just held on by 4 clips.
Put some material around the shifter's shaft at the trans and put the Boot and surround back down.Just don't use too much so that the shifter is hindered by the insulation or matting..