The tyres are standard size- I insist on this for 2 reasons:
1- The car looks totally standard, even MX5 car club members and Mazda dealers cannot pick it as having been modified (except for the massive front brakes
) until the engine is started; this is very important to me- the ultimate "Q" car concept 
2- The limited traction of the rear tyres is what saves the diff and half shafts from destroying themselves.
I've tried many different tyres on the car and thouroughly recommend continental conti-sport contact 3's.
They will often take full throttle in second and almost always in third without breaking traction. Of course you need to roll the throttle on rather than snap it open, and the tyres need to be warmed up first...
Second runs to 102km/h, so 0-100 km/h time seems to be about 3.5 secs without a need to change gear.
Achillies 123s were remarkable, they easily cope with the torque and are very cheap- unfortunately being lower profile they reduced my ground clearance too much.
Having a lightweight car with all that torque at really low rpm (400Nm at 1000 rpm
) means that the car is incredibly easy to drive, even in town, any gear will do- Really!The electronic throttle of the LS3 really shines here- it's so progressive and smoothly linear that the car is easy to drive without wheelspin or jerking. it really controls the torque output very smoothly. As you say, tubo cars can be a real PITA in town...
The engine was brand new crate motor from Ebbetts here in Hamilton.
I imported a new gearbox from Holden Australia, the Cobra and Mustang parts to modify it came from the States.
The Engine Management system and Brakes are from the States, but both required a fair bit of modification to fit MX5.
I've put the car in "the garage" part of this site, but don't know if you can see it yet...
