Guran's NA6 "Little Reddy"

[evil_weevil]

Hey Bryan!
Was great to meet you on sunday!

Congrats on the PB mate! that is stonkering quick!!!

I wasnt going to do my 4th run...but my wife said to harden the fuk up and go out! So I did haha
last lap last session got under 2mins!

Still plenty of time to make up for me!

[Guran]

I bet you're glad you hung around Chris. That 2 minute barrier must have looked impenetrable until then. It's amazing how it can all just come together for that one magic lap.

I have another Supersprint at Eastern Creek coming up on 29th August. My goal is to beat that Class 1A record of 2:00.61 and then I'll be hunting for a 1:59 which will beat my previous best time in my MINI Cooper S (2:00.0 at a Driving Solutions trackday on 22nd Jul 2008).

I'm starting to think about my next set of R-specs too. My current set of RE55S tyres were secondhand when I bought them and they've lasted me five Supersprints (OPGP x1, EC x2, WP x2). They will be OK to see out the season (one more round for me), but are probably too far gone for the MX-5 Nationals regularities at Wakefield Park in October (if I decide to enter).

[evil_weevil]

Im tempted to do that round on the 29th of August but will have to see how the mortgage is going first

yeah I must admist I tried a few different lines and different gears, I thought it wasnt working as well as I hoped but yeah! stoked to finally crack it!
now its 1.58's next time

my r888's are getting a bit worn so time to look at tyres soon for me!

[Guran]

I just swapped the wheels on Little Reddy and thought I might as well stick them on a scale to check their mass.

Bridgestone RE55S on stock 14" daisy alloys = 12.9kg (including lots of rubber marbles stuck on the surface)
Bridgestone RE001 on stock 14" daist alloys = 13.7kg

I was quite surprised that the R specs where lighter since I was expecting the stiffer sidewalls to add weight. But you can definitely feel the difference when lifting and moving both of them.

[Hellmun]

Think I figured out why I was slower than normal. Looks like I pushed the limits of the kumho's a little further than I should've

Now to find tyres in the next week....

[Guran]

Bah. Slicks are meant to be quicker than R-specs!

I noticed Mike had the same issue as you with the middle third of the V70A tyre width wearing faster than the outer two thirds. Must be a variation in compound or something like that.

[Hellmun]

The D01J and V70 have done it though both were 225mm wide. Unfortunately you lose a decent amount of grip once you get past the good rubber... they were brilliant the previous 2 days at wakefield but Eastern creek was just a little too much. I got much better wear on my previous set though... These have done 8 trackdays and a couple I've only done 2-3 sessions during.

[Guran]

The latest issue of MOTOR arrived in my mailbox earlier this week and I've been devouring the "Bang For Your Bucks" section. This is one of my favourite features they do each year, because it's a comprehensive track thrashing of a large number of current model cars. I just wish they'd figure out how to do their sums properly because their numbers are never reproducable. At least they include the raw data.

So tonight I was scanning through the corner speed data for Warren Luff's laps of Wakefield Park and thought ... jeez those numbers aren't anything special. I pulled out the laptop and checked my PerformanceBox data from the club run on 21st June. Here's how my best lap (1:17.00) compared with MOTOR's BFYB best (and where my lap would have finished if included in the list):

Turn 2: my NA6 85.40km/hr, MOTOR (370Z) 82.21km/hr ... 1st
Turn 3: my NA6 113.28km/hr, MOTOR (GT-R) 117.66km/hr ... 6th
Turn 5: my NA6 83.82km/hr, MOTOR (Clio Cup) 83.60km/hr ... 1st
Turn 8: my NA6 64.04km/hr, MOTOR (GT-R) 66.45km/hr ... 2nd
Turn 10: my NA6 56.38km/hr, MOTOR (330d) 60.82km/hr ... 9th

Wow! I would never have thought my 18 year old stock MX-5 on street tyres would be quicker through turns 2 and 5 than everything in the BFYB field, including GT-R, 370Z, Clio Cup, Golf R/GTI/GTD, BMW 1&3 series, and WRX. And they were also being dríven by a pro racing driver!

It wasn't just this version of BFYB either. I checked some back issues, and their previous fastest speeds on turn 2 were 84.04km/hr in 2009 (370Z), 85.46km/hr in 2008 (Clio 197), and 85.89km/hr in 2007 (Elise S). Just goes to show how good the original MX-5 really is!

The other interesting thing I noticed from the graph below is that Wakefield Park is definitely a "power circuit". Vmax is closely related to kg/kW because it's all about straight line acceleration. A nice handling car like an MX-5, Elise, 370Z, STi (not current version), XR4 or MR2 can be a few seconds quicker than an average car with similar Vmax on the straight. However, an extra 10km/hr Vmax will shave a similar amount off the laptime. Perfect example of this point is the Aurion Sportivo in 2007, which lapped in 76.1s thanks to a 167.1km/hr Vmax and crap handling.

[Jeo]

Wow! That's really cool.

[CoffeeBoss]

The other interesting thing I noticed from the graph below is that Wakefield Park is definitely a "power circuit".

As was once said to me, look at it this way - the 3 tightest corners at Wakefield all have straights directly after them. So this alone rewards power and particularly when it's combined with good mid-range torque.

So glad you have the time and inclination to do all this, I always find it quite fascinating.

Three cheers for MX5 Cartalk's #1 Data Miner!

[broady]

Nice stats Bryan!

[Charlie Brown]

Bryan, I too got the magazine on the weekend and looked at those lap times and speed through the various corners and was surprised at what was achieved or not as the case maybe.

I know that Luffy punted a stock NC & SE around Wakefield a number of years ago and turned in a time of around a 1:14.3, so it was an interesting comparison plugging that number into the BFYB table.

When I instruct "first timers" on Club days about the speed to carry through Turn 2 (Turn 1 in the Mag), I show them how easy it is at 80kph on street tyres, so to see the Mag figures and know that the MX-5 gets through there quicker is a real buzz. The other corner that stood out was Turn 3, which a full flight MX-5 can do around the 125 – 130 mark (ie almost on the rev limiter in 3rd gear in a 6 speed box), the mag figures were way lower even allowing for speedo error.

Those photos : I just hope that it was for the photo shoot that they rode the inside ripple strip on Turn 3 because if they did that during their time lap it’s no wonder some of the times weren’t impressive. That Alfa was awfully crossed up.

It's not a fair comparison but it just goes to show you that if you throw a couple of grand into the MX-5 NC with some R-Spec tyres and a few suspension mods, you can turn in a high 1:10s - low 1:11s lap after lap, then for the price the MX-5 is pretty good compared to the cream of BFYB.

[Guran]

Thanks for the comments guys. I must be a bit demented, but I get a kick out of data analysis. It's a nice challenge to take a heap of raw data, make some sense out of it, and demonstrate a fundamental trend from it.

CB - Luffy's best in an MX-5 was at the last BFYB in the Aug 2009 issue, in an NC2. It was a 1:14.1 (Vmax 155.21km/hr) and it's the pink data point indicated by one of the arrows in the above graph. Corner speeds were as follows:

Turn 2: my NA6 85.40km/hr, MOTOR (NC2) 83.04km/hr
Turn 3: my NA6 113.28km/hr, MOTOR (NC2) 112.51km/hr
Turn 5: my NA6 83.82km/hr, MOTOR (NC2) 81.84km/hr
Turn 8: my NA6 64.04km/hr, MOTOR (NC2) 63.08km/hr
Turn 10: my NA6 56.38km/hr, MOTOR (NC2) 59.89km/hr (I need to practice this one more!)

There you go, my NA6 is quicker in most corners than an NC2! Fair enough though, Luffy only gets a few laps to set a quick time, and I've had over 300 to get this far.

Keep in mind that these are all minimum speeds logged in each corner, and often this is only seen for a fraction of a second, as your speed usually drops and then climbs through the corner. They are also actual speeds logged via GPS, rather than what shows on the speedo (which is usually higher). When I take turn 2, I usually check my speedo just as I reach the outer ripple strip on exit and if it says less than 100km/hr there, I know I haven't done it right.

As for the airtime shown in the photos, yes I expect the ripple clipping is done just for the action shots. The Alfa Mito looked almost ready to rollover. I wouldn't be surprised if they roll a test car in the not-too-distant-future.

You're also dead right about what you can achieve with a modded MX-5. R-specs alone are worth about 2 seconds, so that'd bring a stock NC2 down to 1:12s, which IMHO is the best "bang for your buck" as a mod. Factor in another couple grand for coilovers and suspension tuning, and there's another second or so ... high 1:10s - low 1:11s. Pretty incredible really, from a "hefty" 9.6kg/kW.

[CoffeeBoss]

the MX-5 NC with some R-Spec tyres and a few suspension mods, you can turn in a high 1:10s - low 1:11s lap after lap

Yeah, you can Phil

I need to get out there more.

[sliq]

mind boggling stuff. good work.