NC Wheels (part 2)

[LuckyCat]

Hi
looking at the discussion regarding wheels and tyres for the NC, I have come to the conclusion that the best aftermarket wheel / tyre combination would be 17x7 and 205/45 17 tyres. For the simple reasons that there has been a statement about the "fastest NC around Wakefield uses stock rims and R Spec tyres". So it's really about the look, and the rubber.
As wheels like Advans and Enkeis are lighter and have different offsets they would be classed as "performance enhancing modifications", yes or no?
And as these wheels don't seem to come in the +55 offset, just by adding the wheels puts me out of Class 3 and into Class 7 where there's probably a whole lot of fast NC beasties.
So I think I'm going to put off my mods until I can get some more track time.....with the standard car. But maybe a sports muffler anyway.

cheers
Chris

[deanb90]

I wouldn't consider a wheel a performance modification, it's all in the tyre.

put it this way, when I replaced me standard wheels for my 17x9 bbs wheels, I couldn't tell the difference in speed. it was prob there as they are heavier but I couldn't notice it. go with what you want, but put it this way, 17x7 has proven to be enough width for an nc.

[Jeo]

Assuming you're looking at the NSW Club days?

Don't know how it works under the current rules but my understanding of the previous rules was that a stock car was exactly that, stock. Changing wheels is quite plainly a modification.

[Guy_Coles]

The rules and regs can be found here as to what class you would have to run in with but they are not quite specific as to what is considered an acceptable number of mods on an NC : http://www.mx5.com.au/nsw/PDF%20Content ... 9-2-12.pdf Perhaps as we see more NC's on the track - this might change.

The more Club Members we get will make it a better experience for everyone

Depends on what you are trying to achieve, if you are after club points and standing, just run slicks - very few if any run them so you could do a 1:39 and still come third on a bad day............... Run R-Specs and do a 1:14 you might come 6th.....

[Guy_Coles]

The rules and regs can be found here as to what class you would have to run in with but they are not quite specific as to what is considered an acceptable number of mods on an NC : http://www.mx5.com.au/nsw/PDF%20Content ... 9-2-12.pdf Perhaps as we see more NC's on the track - this might change.

Depends on what you are trying to achieve, if you are after club points and standing, just run slicks - very few if any run them so you could do a 1:39 and still come third on a bad day............... Run R-Specs and do a 1:14 you might come 6th.....

[Charlie Brown]

Hi
looking at the discussion regarding wheels and tyres for the NC, I have come to the conclusion that the best aftermarket wheel / tyre combination would be 17x7 and 205/45 17 tyres. For the simple reasons that there has been a statement about the "fastest NC around Wakefield uses stock rims and R Spec tyres". So it's really about the look, and the rubber.
As wheels like Advans and Enkeis are lighter and have different offsets they would be classed as "performance enhancing modifications", yes or no?
And as these wheels don't seem to come in the +55 offset, just by adding the wheels puts me out of Class 3 and into Class 7 where there's probably a whole lot of fast NC beasties.
So I think I'm going to put off my mods until I can get some more track time.....with the standard car. But maybe a sports muffler anyway.

cheers
Chris

Correct the fastest NC around Wakefield is Chris Gough (MX-5 Racing) running the stock rims with Kumho V70a 205x45 R-Spec tyres. He has spent many laps, days & years testing and retesting and laps in the high 1:09s to low 1:10s. Part of his business is suppling race ready and prepared track and targa NC’s to time short people. The fastest Club members with modified road registered NCs are Ralph and myself running in the mid to high 1:10s. Ralph with 215x45x17s & 4.1:1 diff and myself with 225x45x16. The fastest stock NC is Julian with a 1:14.38, OEM tyres.

Chris, in your case you are far better off starting in the stock class where the only changes allowed are things like alignment, brake pad/fluid and tyres that aren’t R-Spec. This makes for very close times and the only real difference is the driver and it’s easy to see how you are performing compared to everyone else. As you learn the track you’ll find that you’ll be analysing each corner to work out how to go quicker and each braking point to see if you can go deeper.

Once you get to the pointy end of the standard class you can start thinking about mods. The biggest improvement in times isn’t a sports muffler but sway bars and R-Spec tyres. By choosing the 205x45 tyres you keep the weight down as well as the rolling diameter. Step up to a 215 and you’ll notice the difference (drop) in acceleration. Ralph dropped a second by fitting the 4.1 diff. Time improvement from then on is like a ‘J’ curve with x=cost and y=improvement. You can spend a lot and not get much out of it.

I wouldn't consider a wheel a performance modification, it's all in the tyre.

put it this way, when I replaced me standard wheels for my 17x9 bbs wheels, I couldn't tell the difference in speed. it was prob there as they are heavier but I couldn't notice it. go with what you want, but put it this way, 17x7 has proven to be enough width for an nc.

Dean, FYI the stock rim weighs in at 7.7kg, your BBS weighs in at 9.3kg but that’s not the end of the weight story. You should also consider the weight of the tyre because a lighter tyre can offset a slightly heavier rim. Obviously the lightest rim / tyre combination is the best but then the quality of the tyre comes into play.

To give you an example, at one stage during my NC ownership I fitted some 215x45 Toyo T1Rs to the stock rims. All up they weighed 17.7kg. Now with 215x45 Michelin Pilot Super Sports the weight is 17.25kg. My 16x8” RX7 track wheels with 225x45 Kumho V70A’s weigh in a bit less at 17kgs.

You can easily check the weight of your tyres on Tirerack.com.

I’m looking forward to the NatMeet Wakefield track day where we are running street tyres (no R-Specs) to see what a modified NC can do. It will be interesting comparing the Michelins to the Kumho KU36s that some will be using. I just hope we can beat Julian’s stock time.

[LuckyCat]

Points all taken, and appreciate the advice. I've got a set of mods I'd like to do, but as the regs go, once the car's modified I'm in a different class against cars that against my only track day, are 12 seconds faster.
Still the attraction of having a nice set of wheels and a sports exhaust...well I can keep that for the street and just revert the car to normal for track day. Although it will be a pain. In any case I'm out to have some fun, not to worried about accumulating points, but do want to learn what the car and myself can do..in controlled conditions.
Small steps...

chris

[LuckyCat]

Once you get to the pointy end of the standard class you can start thinking about mods. The biggest improvement in times isn’t a sports muffler but sway bars and R-Spec tyres. By choosing the 205x45 tyres you keep the weight down as well as the rolling diameter. Step up to a 215 and you’ll notice the difference (drop) in acceleration. Ralph dropped a second by fitting the 4.1 diff. Time improvement from then on is like a ‘J’ curve with x=cost and y=improvement. You can spend a lot and not get much out of it.

I'm interested - Ralph dropped a second by installing a lower ratio (4.1) diff? I would have thought that a lower diff would give more punch, even though top speed would be lower?

Chris

[Charlie Brown]

I'm interested - Ralph dropped a second by installing a lower ratio (4.1) diff? I would have thought that a lower diff would give more punch, even though top speed would be lower?
Chris

Yes far better out of the corners and a lot smoother under brakes for T8 & T10 at Wakefield with less chance of locking a rear wheel by not getting the revs high enough.
As for top speed, Bathurst maybe the only track in Australia where you can peak in 6th but I'm only guessing. Phillip Island is faster than Eastern Creek and I only just grab 6th there nearing the end of the straight with the 3.7 and Ralph didn't max out with the 4.1 in 6th.

[Sailor]

You do realise that you're gonna cost me a diff don't you!?

[deanb90]

^ do it. so worth it.

[Charlie Brown]

You do realise that you're gonna cost me a diff don't you!?

I keep telling you that the 4.1 is no good with the S/C. Leave the 4.1 for someone else.

[Sailor]

I've got lots of big fat 235 rubber to handle the power and could even go 9" with bigger for the track
and if it doesn't work well...I'll just sell it to you

[Regie]

I've got lots of big fat 235 rubber to handle the power and could even go 9" with bigger for the track
and if it doesn't work well...I'll just sell it to you

Or sell it to me