Which MX5 for Vic Sprint Series?

CrazyRacer · Postby **CrazyRacer** » Sun Jun 21, 2015 2:04 pm

I'm looking to get back into some cost effective motor sport and doing the Victorian MX5 Sprint Championship seems like a good option.

I'm not a newbie to motor sport having won a club sprint championship and competed in Vic State Racing and Vic Club Rally Series. That was all a few years ago now, but still I've got a reasonable idea of what I'm getting into.

The plan is to have a road registered car which will be a weekend road/track toy, but not a daily driver. Probably looking to run in the Clubman class to start with, but may move to one of the modified classes as my urge to tinker takes over.

My main question is whether there are better models to start with for these particular classes, or do the rules pretty much even the play field across the different models?

Does ABS and a few extra kw make the NB8B a better track car, or is it better to get and earlier model and save the money for mods?

Previous experience crewing in GT Production would suggest that road tuned ABS doesn't work very well on track, but that was on a Proton with slicks, so maybe its different for an MX5 on road oriented tyres.

My other questions are around my ability to fit in a car with various seat and roll bar combinations, but I think that will only be answered by attending some meets and asking nicely to sit in some cars.

Any ideas or suggestions you can give are much appreciated.

davekmoore · Postby **davekmoore** » Sun Jun 21, 2015 2:35 pm

Anything with over 150rwkw will put you into Open with me so you can show people how slow I really am.

rascal · Postby **rascal** » Sun Jun 21, 2015 2:45 pm

Dave, actually anything over 125rwkw puts you in Open...

to OP, if you are targetting Clubman to start with, then this year we have introduced 2x clubman classes. One for NAs and one for NBs. We also allow exhaust as a free mod for na6s in NA Clubman and non VVT models in NB Clubman. Both of these changes were to hopefully mitigate the previous unfair advantage that NB8Bs used to have in Clubman class.

Therefore it 'shouldnt' matter which model you choose, (NA6, NA8, NB8A or NB8B) for clubman classes your car should be able to be competitive.

ABS is a real advantage in the wet, otherwise not so much, other than reducing chance of flatspotting tyres...

Postby **beavis** » Sun Jun 21, 2015 3:46 pm

CrazyRacer wrote:Does ABS and a few extra kw make the NB8B a better track car

Yes.

CrazyRacer wrote:Previous experience crewing in GT Production would suggest that road tuned ABS doesn't work very well on track, but that was on a Proton with slicks, so maybe its different for an MX5 on road oriented tyres.

The ABS isn't too bad. A set of Yokohama AD08R's would do perfectly.

CrazyRacer wrote:My other questions are around my ability to fit in a car with various seat and roll bar combinations, but I think that will only be answered by attending some meets and asking nicely to sit in some cars.

If you are under 6foot or so, you will be fine.
If you are under 6foot4 or so, you will be fine but a little uncomfortable.
Anything larger would just suck.

CrazyRacer wrote:Any ideas or suggestions you can give are much appreciated.

I saw a black NB8B for sale for $7500 at the moment, buy that and get some good tyres, hawk blue brake pads, and enjoy a cheap track car.

CrazyRacer · Postby **CrazyRacer** » Sun Jun 21, 2015 7:08 pm

beavis wrote:If you are under 6foot or so, you will be fine.
If you are under 6foot4 or so, you will be fine but a little uncomfortable.
Anything larger would just suck.

Just on 6 foot, but mainly in the legs so I tend to need to sit back as far as possible. Used to own a standard NA8 and it was OK for leg room (just), but a bit of a pain as a daily.

beavis wrote:I saw a black NB8B for sale for $7500 at the moment, buy that and get some good tyres, hawk blue brake pads, and enjoy a cheap track car.

Yes, I saw that one. Might have to give him a call.

mazmad · Postby **mazmad** » Mon Jun 22, 2015 2:31 pm

Beavis is on the money, NB8B is a great choice. The ABS is pretty effective on the track, provides brake bias, you wont notice it. If you buy an NA and you do tinker you will ultimately upgrade it to NB gear anyway.

lightyear · Postby **lightyear** » Mon Jun 22, 2015 7:37 pm

The best bang for buck is an NB8B. Change diff to 4.1 or 4.3 Torsen $600 change over. (I have a newly rebuilt 4.1 Torsen for sale) Exhaust, extractors $600-$1000. Pod filter $20. B.C coil overs $1100, maybe a big front sway bar. 15x8 or 9" lightweight wheels and a set of Nitto Nt01's $1600
Skip clubman class. It's not much fun with an open diff. Mod, or super mod is more fun. You don't want to run around Phillip Island doing 2:00 plus.
So by the time you buy some safety stuff and seat your looking at $5000. Add$7,500 for the car. And for $12,500 you have a reliable fun car that can hold its own against "quick" cars.
You could add lightness by removing a few unnecessary items.

Ned Loh · Postby **Ned Loh** » Mon Jun 22, 2015 8:22 pm

I always thought VVT gave more bottom end, and made a better road car, but the NB8A had a better top end (despite Mazda publishing a higher number for the VVT). I think maybe Mazda felt they had to show an increase. Some interesting info here:

http://mazdaracers.com/topic/5090-vvt-9 ... on-thread/

http://mazdaracers.com/topic/3339-parit ... entry44476

CrazyRacer · Postby **CrazyRacer** » Mon Jun 22, 2015 8:31 pm

lightyear wrote:Change diff to 4.1 or 4.3 Torsen $600 change over. (I have a newly rebuilt 4.1 Torsen for sale)

Hows the Torsen go vs a clutch type LSD such as a Kaaz. I've only ever raced on either an open diff or welded locker and have to agree that an open diff around the Island is not much fun.

lightyear wrote:B.C coil overs $1100, maybe a big front sway bar.

What are most people running for coilovers. I'd not really heard of Yellow Speed until I started looking around this forum. MCA gets a great rap and I've heard good things about Shockworks too, though not specifically in relation to MX5s

lightyear wrote:15x8 or 9" lightweight wheels and a set of Nitto Nt01's $1600

Do 15s fit over the NB8B brakes OK or do you have to careful which wheels you select. 15s would probably mean cheaper tyres. Are Nittos the go, or just best bang for buck. Yokie A050 get talked about a lot, but they're hideously expensive.

lightyear wrote:Skip clubman class. It's not much fun with an open diff. Mod, or super mod is more fun. You don't want to run around Phillip Island doing 2:00 plus.

I could see myself ending up in one of the modified classes, but it might be a slow progression (or maybe no so slow) as the car develops.

Thanks for the feedback

lightyear · Postby **lightyear** » Mon Jun 22, 2015 9:01 pm

Torsen is fine. That's all I have ever used. I would go B.C for value for money. Same with the Nitto's. 15's fit over NB8B brakes.

Ned, VVT is better. I made more power with a stock NB8B than worked NB8A cars with ECU, etc. I only had an elcheapo exhaust.

mazmad · Postby **mazmad** » Mon Jun 22, 2015 9:21 pm

NB8B got ABS. Torsen sucks, if you have stuff suspension. Just go a locker if it's a track only car.

rascal · Postby **rascal** » Tue Jun 23, 2015 10:41 am

CrazyRacer wrote:Hows the Torsen go vs a clutch type LSD such as a Kaaz. I've only ever raced on either an open diff or welded locker and have to agree that an open diff around the Island is not much fun.

It's even less fun around Winton.....

If given the choice then I'd go for clutch type every time for track work. Torsens can still light up the inside wheel when unloaded, whereas clutch type just grip and go. We've had a couple of guys in the club put in a torsen after a open diff,. and then end up doing it a second time as the torsen wasnt doing the job well enough.

CrazyRacer wrote:Do 15s fit over the NB8B brakes OK or do you have to careful which wheels you select. 15s would probably mean cheaper tyres. Are Nittos the go, or just best bang for buck. Yokie A050 get talked about a lot, but they're hideously expensive.

All the NB8Bs in clubman class currently run 15s, so 15s mostly fit, but just be careful as some don't.
R Specs will put you into Modified class, (AD08, RS3 or DZZ1/2 for Clubman) but if thats ok then Nittos are the best bang for buck (in my experience 3x - 4x cheaper than A050s) however A050s are definitely the superior tyre. Maybe 0.5 to 1.0 secs per lap quicker.

lightyear wrote:Skip clubman class. It's not much fun with an open diff. Mod, or super mod is more fun. You don't want to run around Phillip Island doing 2:00 plus.

You don't need to run the open diff for clubman. All the current NB clubman cars have LSDs as one of their permitted mods..

Also, the current clubman record is 2:02 around the island, and I challenge anyone to suggest they aren't all having a ball. You don't have to be the overall FTD to be having fun, and doing a 2:02 in a clubman class car is still driving the wheels off the car.

CrazyRacer · Postby **CrazyRacer** » Wed Jun 24, 2015 12:18 pm

Thanks everyone for the advice.

Unfortunately I'm going to have to put my MX5 plans on hold for a few months as I blew my Achilles tendon playing squash on Monday night and wont be driving anything for a while.

I've learnt my lesson now... squash is dangerous, motorsport is much better.

Once i'm on my feet again I'll come and track you guys down at one of the sprint meetings.

Cheers
Simon

rascal · Postby **rascal** » Wed Jun 24, 2015 2:07 pm

Sorry to hear about your injury, though you are correct. In all the years the club has been running motorsport events, we have never had even one single Achilles tendon injury...