mx5cartalk.com

I recently acquired a 1998 NB and am planning a return to motorsport after 35 years away. Is there a class for standard unmodified MX-5s?
Would changing to coilovers put me out of that class?
Any other advice welcome.

What State are you in, so you get relevant answers.

As per Luke's post.

Are you a member of a club, if so check their rules.

If you are running in a series check their rules.

QLD has changed their MX5 club rules for Motorsport and there are no car classes rather 4 'groups'

I am in NSW.
I joined the MX-5 club of NSW
I have been to the January meeting of the Hunter chapter. Could not get to the Feb meeting as we are away in Tasmania (without MX-5).
Working towards competing in Targa Tasmania 2018 in the GT Sports Trophy class.
I intend to do club track days, hillclimbs etc. and possibly on to supersprint. Probably wont go as far as 'door to door' racing as i want to keep using the car on the road.
I don't want to make the car un-useable on the road or even uncomfortable on the road.
I am getting a CAMS approved roll bar. Have ordered suspension bushes, cam belt and water pump.
Need advice on suspension, tyres and possibly wheels, seats, belts helmet, clothing and anything else i haven't thought of.

The best advice is to read the rules in which you are competing and build the car to suit. Problem will be that small variations in rules that may bump you out of your chosen group. This could impact tyre, wheel, seat, suspension decisions. That being said CAMS/FIA approved seat, harness, helment, clothing and frontal head restraint are a given.

I have built my car to compete in a certain class/event, for other events it just fits in wherever those rules allow unless it is simple to make the change.

For example
Time Attack QLD - Performance Class
Must have OEM doors. The door trims and inner door skins can be removed. The structure must remain

WTAC 2017 - Clubsprint (Each vehicle must be presented as per the OEM vehicle (see definitions) apart from the freedoms allowed in these regulations. The rules are such that if it is not specifically stated then you CANNOT do it.
Original door trims must be retained

As you're from the Hunter region & thinking of doing hillclimbs, I will use MGCC Newcastle Ringwood hillclimb as an example:

They operate basically according to Cams rules, & there is a Type 1 class for unmodified cars. The only changes allowed from factory are fluids, brake pads, air filter element, tyre brand, race seat & rop fitment.
Coilovers, exhaust, suspension bushes, wheels, sway bars changes etc would make you Type 2. You can keep modifying up to types 4 & 5 which are full on sports sedans.
However, MX5's can also compete in the Marque Sports class, which allows a lot of mods according to the Cams marque sports regulations.

The NSW MX5 club also run hillclimbs at Ringwood, & probably have their own classes.
If you are not racing, I personally think you are better off building the car you want. There will be a class it will fit in, at all club level events.
However, if you want to be competitive at Targa Tas, then build to suit the class you want to be in.

I had a look at the supersprint regs and was thinking of going for Type 1 but having second thoughts as i would want to fit different shock absorber internals, possibly bilstein.
Now having thoughts of going type 2 so i need to check if coilovers are acceptable for type 2

Type 2 appears to allow coilovers and allows me to play with spring rates and sway bars. Also allows EMS Modifications and a 2" increase in wheel diameter and 1" increase in wheel width. Exhaust is free but must be legal for the road.
So for track days i can lower and bring it back up for the road and for Targa. Could even use stiffer springs for the track.