What group do you run with?
I intend to run the miata on the track this summer for the 1st time, so I'm thinking of a slower track like gingerman. But I haven't found a local group to go with.

Check out "Wangfest" on FB. There are a bunch of local groups running small events on Gingerman, not to mention their plethora of open track days. Many Chicagoans go out there, great beginner track. Autobahn down in Joliet is fantastic also, but is typically more expensive.

I have the RB front and I'm pretty sure it is the tubular front with a RB solid rear. the rear is a 16mm, Ive heard you really do dont need more then a 14mm in the rear. I ordered a 11mm off ebay ( they did not say what size it was) for 30 bucks shipped. I knew it would not be right long term but i wanted something smaller and cheap, it is on the car now. for now I prefer a car that I can push and wont over steer on the high speed stuff. obviously I have lots of suspension tuning stuff to deal with but for now i'm ok throwing a little money at a set of springs and a sway bar just to drive the car. I'm pretty sure I'm have 2' springs 2.25 id perhaps but not the 2.5 six shooter posted

I apreciate the help, going to double check an order something, 550 sounds about right.

as for the balance set up. I dont know, I'm new to the miata stuff, very new, but several track guys said the rear RB bar is too much. so far I agree but I'm going to hold on to it just in case I change my mind. I raised the car significantly about 2-2.5 and have not done an alignment. I did some basic measurements and it seems close so I have other things to deal with, tire temps were good, tire wear good. I/m sure my toe is off in the rear, after raising the the car 2+ inches and could contribute funny stuff on track.

I am not sure that 448/337 is such a bad setup really. the 16mm is a bit on the big side, but it didn't seem all that out of whack, especially since there is a couple of guys around here running 450/350 with an RB front.

I would definitely get a good alignment and play around with tire pressures and see how that affects it. Lastly, make sure you are running a bit of rake in the rear and that your coilovers aren't at random/odd heights (which would mess up your corner balancing).

I took off the 16mm RB and put a 11mm just to see. I need an alignment, I raised the car about 2-2.5 inches and have not done an alignment. I want to do it myself and ive not had the focus to sit down and really DOIT or the money to buy tools to make it easier ( yes I have string and a jackstand).

the other possibility is that my rears are bottoming out.in order to achieve my ride height I had to remove the custom rear upper shock mount ( it was the prototype miata coilover set up from Stance fyi stance is in Chicago super cool guys) and replace it with a Stance one that is flat, like the one used in the front.this achieved the right ride height, but it removed some travel so it might bottom out which would explain the oversteer.

it is not such a bad set up, it feels pretty ok, it just needs some tweaks. I said it sucks but it didn't suck, it needs some development which is to be expected coming from a drift car.

Miatas are pretty sensitive to rear toe so that is likely a good portion of your problem. It also takes surprisingly little rear sway bar to make pretty drastic differences in handling.

On my car with 600/375 springs the OEM rear bar I have can be deflected an inch or so by hand to get it in position when I take an endlink on/off. Without it it's an understeering pig on track with it on it's a hand full at autocross because the ass end wants to be first all the time.

Yeah, but they run the biggest RB tubular bar and zero rear sway bar to be able to achieve balance.

I was trying to help him keep his sways and springs as much as possible and further increase rather than decrease his roll resistance. I'm trying to use what he has and get better, not go backwards with regard to capability. It will all work, though.

I run with many different car clubs and NASA. Im pretty involved with the audi club because it is a fun group and it is a great group to start with and really focus on making to a good experience for noobs. all different types of cars are welcome but you do need to join the club for 40 bucks but this is the case for most clubs.