The ratio of front to rear spring rates can have a big effect on what sway bars work best. To give you an idea, I bought the Whiteline 24mm/16mm kit when I first built my car. The first springs I used were 400lb front/300lb rear (a ratio of 1.33:1). With both Whitelines, the car was OK on the road b...

Cheers Cole
I'm picking the car up this afternoon so it will be good to see how it looks with the dash back in etc.
I've had the side intrusion beefed up a bit since you saw it.

Hopefully I'll never need to test it out!!!!

The 1.8 NA has a 4.1: axle ratio and a 0.814:1 5th gear.
Depending on what tyres you have: 185/60x14 = 551rev/km, 195/55x14 = 558rev/km (according to the Miata.net tyre size calculator)
At 100km/h on 185/60s the revs will be: 551x4.1x0.814x100/60 = 3065

Authority cards cover:
Competition safety harness
Roll protection that extends forward of the front seating positions and/or modifications that effect the interior impact rule
Removal of an airbag SRS system
Braided hydraulic brake lines
Hydraulic handbrake
Plastic glazing.

Head clearance from the hoop can be an issue in an MX5 if you are tall, as Euan has mentioned. My roll bar fits under the soft top OK ( the builder made it to do so) and clearance isn't a problem even with my race seat on the original MX5 seat runners. I'm 1.73m.

I found a guy in Hamilton who will make MANZ approved bolt-in roll bars for MX5s. He hasn't done one to the new specs with the larger main hoop diameter yet, so the final price is subject to confirmation, but he reckons they should be around $500. This is for a design to the minimum MANZ spec - main...

Shipmytrade responded with a quote within 15 minutes, so their comment about deleting your email was probably true.
They wanted $158 to ship my seat to Dunedin, so a good reduction on Mainfreight.
The seat was eventually sold to a local guy, but I've learned a bit a freight costs.

I am selling my current race seat as I'm going to a full roll cage and it won't fit with my Racepro seat. I have someone in Dunedin interested in buying it but Mainfreight want $240 to ship it. Does anyone know of cheaper freight companies? The volume is 0.4m3, so it's too big to go by NZ ParcelPost...

MANZ rules for racing are a bit Catch 22. You don't have to have a roll bar or cage to race, but if you have got one, it must be built to MANZ specifications and homologated. The cost for a MANZ spec roll bar, with main hoop, rear supports and a diagonal (the minimum allowed) will be +/-$1000. A fou...

I think the NB bushes are the same as the NA's, but check with Emilio who runs 949 Racing, emilio700@yahoo.com, he can confirm.

A new race class has just been launched in Auckland.
This looks as if it would suit road going MX5s which have good suspension and brakes setups, but no power mods.

There's plenty on the web about the benefits of slotting, but for trackday use only I doubt you would see any benefit. I did several seasons of full racing with the standard brake rotors and never had any glazing or fade problems.

Thanks to all for their comments and suggestions. I am currently running a splitter/undertray that covers the underside of the engine back to the rear end of the sump. This, together with the rear wing, is giving me a stable car at up to 230km/h and good lateral grip (around 190 km/h round the sweep...

If you want to check out whether it is the O2 sensor PM me, I have a spare one you can borrow to try.

Your exhaust temperatures are not likely to exceed 700C under normal driving conditions, only during sustained track driving, and then probably only marginally.
I don't have any personal expericence of HPC coatings but those I know who have used it have been pleased.

Has anyone in Auckland got an NA with a factory (or an MX5Mart) front lip spoiler I could look at?

I want to see whether it's possible to fit an effective splitter.

Thanks

Keith

E93A Ford Popular Austin Healey Sprite Mk1 (my first race car) Alfa Romeo 1600GTA (aluminium body) Toyota Corona Mazda 618 Mini Clubman Mazda 808 Mazda 626GT Bluebird (company car - uuurgh) Commodore VK 3.3 (better than the Bluebird for towing the racecar) Nissan Skyline (betwen racecars) Commodore ...

I tackwelded the studs to the manifold, and, together with the downpipe to bellhousing brace, I've never had any problems with the turbo coming loose in 5 years of regular racing.

I'll be geting some photos soon and will post them.

My 4 pot Big Brake Kit from Goodwin only uses the standard 1600 rear pads as well, and the brake balance has been perfect, even under full race braking. If they have done their homework properly with the 6 pot kit (which I would assume they have knowing Brian), I wouldn't change things. Going to the...

Looks like one of the rollers from the spigot bearing.

14.7:1 AFR is the chemically correct AFR, so it looks as if it's about right at idle. 12:1 is rich, which is on the right side, but maybe a bit too rich.
Around 13 should give good power. How adustable is the Voodoo?

If anyone is thinking of getting Energy Suspension bushings check out
http://949racing.com/energy-suspension- ... miata.aspx

With the current exchange rate they cost me NZ$307 all up and were here in less than a week.

For a good port and polish I can recommend Lynn Rogers Automotive in Howick. Lynn is one the best head men in the country, doing many race engines. I know my own engine has more power (through on-track acceleration and top speed) than other similarly configured engines, which I can only attribute to...

The NA does has a bit of a reputation for body shake. Which is why the first thing peope do is add the two braces underneath, and Mazda introduced the behind seat brace on the later NAs. Whether you have a dog or not is difficult to say, but you are welcome to come for a drive in my road car, which ...