mx5cartalk.com

First of all you are only willing to pay $12,000 for a car then extra for the mods (cage, seats...) or does the $12k include mods??

hard to understand what you are saying in the next bit, you are looking for an NB for $15k with cage, seats harness or you have found an NB already and are asking if this is a good price to pay. if you have already found an NB for $15k with seats, cage wheels suspension and torsen that sounds like a good price to me because stock NB's go for more than that generally. If you are looking to find one for this price then good luck, you might be looking for a while.

Hardtop is preferable for the track, better aerodynamics but a bit heavier

hmm as far as the NB vs NA goes it's up to you really, for a race car I would want a NA8 or an NB not an NA6, depends on if you want it to drive on the street as well, because it's illegal to remove airbags for street cars. The NA8 has alot of parts upgraded from the NA6. The later model NB's have ABS which clutters the engine bay, but they have better brakes and a little better chassis than the earlier NB8A. Could take a long time to go through all the pros and cons.
I'm sure the other forum members can help you alot more with this.

Come have a gander at the Supersprinting NAs and NBs at Oran Park on Sunday! Most of the people there will be happy to talk to you about the pros and cons for their various set ups!

Matt

hmm interesting issue with weight there

NA8 (hardtop) Kerb: 1002kg
NB8A(hardtop) Kerb: 1048kg
without hardtop both would be 22kg lighter
real weight difference is about 46kg

Other things to consider, power steering? do you want it or not, some don't want it for the track others think the mx-5 power steering isn't that bad
NA chassis can be stiffened using a butterfly brace which only adds 12kg but if you have a full cage it should be very stiff anyway.
I'm waiting for the more experienced forum members to help you out as far as choosing between them goes because I have only ever dríven the NB mx5.

Firstly...Don't buy a car and build it up,will cost you a lot more than you think,best to buy one that is built.

If you want to go turbo in the future get a NB.

If you don't want to go turbo get a NA.

My NA race car was 860kg.(no hard top)

My NB SE Turbo race car is 1060kg.(with hard top)

I love the power steering on the NB so I would keep it.

Matildas NA race car will be for sale soon...probably a little bit more than your $12k budget but very close and a great car to start with.

If you want to check out a bunch of MX5 race cars come to Eastern Creek on Sunday or Oran park next weekend.