RE: Fast vs fun - grip or slip

RE: Fast vs fun - grip or slip

Thursday 9th May 2013

Fast vs fun - grip or slip

Is the fashion for big wheels and quest for more grip actually spoiling the fun? PH investigates...



Fast or fun? It's a divisive question, one we explored recently in a battle between our scalpel sharp Megane 265 Cup and Subaru's skiddy little BRZ coupe. At the final whistle, fun took the win, albeit on points, but, judging by your comments, the result continues to split opinion.

To Spa to put our flashy Dunlops to the test
To Spa to put our flashy Dunlops to the test
Ding, ding, round two, and while we will be using the Megane again for this next contest, at least this time it will have much better odds of winning. Why? Because this time we will be focusing our discussion on wheels and tyres. Specifically, whether shelling out on sticky rubber for track use is worth it in terms of extra smiles per mile over a regular road tyre? Can you actually feel the extra grip, and does raising the limit make for a seat of the pants ride?

Provoking this debate was the arrival in the office of a set of new track-biased Dunlops; the Sport Maxx Race. It's intended to be a fit and forget option for track dayers that don't want to faff around with a second set of wheels. Indeed Dunlop bills them as "specially designed to help some of the world's fastest cars perform on some of the world's most challenging race tracks, while ensuring they are able to deliver their drivers back home without the need to change tyres." Which sounds like a challenge to us.

An extra inch
Standard issue wheels on the Megane are 18-inch Tibor rims shod with Michelin Pilot Sport 2 tyres. The optional Speedline Steev gains an inch in diameter, along with a dubious red stripe and a not insignificant £1,000 price tag. Normally shod with Bridgestone, Renault loaned us a set of bare rims onto which we fitted the Dunlops.

19-inch Speedlines shod with Sport Maxx Races
19-inch Speedlines shod with Sport Maxx Races
Now all we needed was a track day. Step forward Renaultsport's annual visit to Spa Francorchamps. This would give us the chance to drive out on the 18s via a mix of B-roads and continental motorway, spank it round the track all morning, then swap wheels and reverse the process. So with the 19s loaded into the boot, fresh tyres leeching a particularly noxious odour, we set off for Spa.

What makes a good track day tyre? Grip, obviously, ranks pretty high on the list of priorities. Although when you're not looking to go purple on every lap, adhesive properties have to be judged alongside durability, predictability, and wear and tear on road car components not necessarily designed to take high loads of mechanical grip. Last but not least, there's the fickle finger of fun to poke into the equation.

Back in the groove
It had been a year since we drove at Spa, but getting into the groove around its sweeping turns and emotive undulations was easy on the Michelin shod 18s. After reducing the pressures at the end of the first session, we found a soft and malleable edge to their grip that, if drawn with a pencil, would be more 4B than 4H.

On the regular 18s for the road trip out
On the regular 18s for the road trip out
Yet when we began to push, those blurry boundaries started to frustrate. There was little to lean on turning in to the faster corners, and on the slower ones it was equally easy to push the Michelins into understeer. It was at this point that the ability of both chassis and driver came into the equation, and providing there's talent in either department the challenge - and therefore fun - comes from working around the available grip. Luckily the Megane's dynamics more than made up for our deficiencies, so by exploiting trail braking, throttle lifts and the brilliant limited-slip diff up front, there was still a stack of fun to be had exploring the peripheries of adhesion.

Onto options
Three sessions later and the Renaultsport Monitor told us we'd slowly chipped away at our lap times, peaking at a 3min5sec. That was the primes out of the way, now it was time to put on the options.

Running a second set of wheels is very popular among track addicts, and for good reason. It's an easy way to transform the handling of your car and it takes away the risk of a long drive home on bald tyres. A set of semi-slicks, such as Toyo's 888, fitted to a lightweight rim can also significantly reduce unsprung weight and inertia. Not here though; the difference between the Michelin shod 18s and Dunlop equipped 19s was an imperceptible half kilo.

Above and beyond service from PR man
Above and beyond service from PR man
Our fumbling fingers had the wheels changed in about half an hour, with a little help from Renault PR man Jeremy. It wasn't really that much of a hassle either, although packing and storing a jack, tools and wheels won't be everyone's cup of tea.

Scrubbing in
First lap on the Dunlops was a very gentle affair, after all, we had no idea what to expect piling into Eau Rouge for the first time on box fresh rubber. Towards the end of the lap, however, both heat and confidence was growing in equal measure. It was immediately obvious they had potential, but we put a leash on our efforts knowing that we'd have to reduce the pressures at the end of the first session.

By the second lap of the next session we were revelling in the increased grip. There was a noticeable improvement in turn-in performance particularly on faster corners such as Pouhon and Blanchimont. Braking traction was considerably enhanced and the extra grip was showing up in the lap times too; over a second quicker from the word go. But more importantly we were having a blast too; our inputs rewarded with immediate and proportional changes in direction. F1 drivers always talk about the importance of good balance in a car. Well, the Megane certainly felt more pointy and responsive with its new Dunlop sneakers on.

More grip and pace on the 19s ... for a bit
More grip and pace on the 19s ... for a bit
Burning rubber
Somewhere along the line we had to find a drawback, and in the case of the Sport Maxx Race it was undoubtedly durability; by the end of the afternoon they were looking decidedly secondhand. Two hot laps around Spa was enough to cook them, by which point the rubber would feel like jelly.

Short-lived as it was, this extra speed was addictive. Having tasted high-grip performance the idea of sacrificing a proportion of it for a degree of mobility, particularly on track days where any kind of intentional drifting is increasingly frowned upon. No one likes driving around understeer, and while the standard Michelins are no slouch in the grip department on-road, the stickier Dunlops let us push that much harder on track.

All of which leaves us in no doubt of the verdict. It's a win for fast, because on track speed most definitely equals fun. So much so that we wouldn't hesitate to add a set of track wheels to our arsenal even if we were doing only a couple of track days a year. But for ultimate gains and with the additional faff accepted we'd invest our money in a lightweight rim and a more specialist track tyre.

Track photography: c/o Peter Helene





   

 

Author
Discussion

Technomatt

Original Poster:

1,085 posts

134 months

Thursday 9th May 2013
quotequote all
I don’t think there are any surprises there.

Pay the money for the track orientated rubber for increased grip at the expense of higher wear rates with an associated knock on effect of a drop in all round performance and longevity for general 24/7 on road use.

It’s just choosing the right tools for the job if that second or two a lap is important.

Technomatt

Original Poster:

1,085 posts

134 months

Friday 10th May 2013
quotequote all
This slip/grip and fun related argument all seems a bit superficial.

For this Megane test, even the higher grip track orientated will transition from grip to slip, you are just pulling a bit more g when it occurs.

Both tyres have the fun quotient, you are just at a different performance level on the track tyre before you access it.

Also, realistically on many track day circuits a high proportion of track day drivers never get into too much slip as the transition to no grip is never that far away, just like the lack of run off and barriers.




Technomatt

Original Poster:

1,085 posts

134 months

Friday 10th May 2013
quotequote all
framerateuk said:
Regarding the PS2.... I've tracked my Megane on PS2's many times and even on some nasty airfield surfaces I didn't notice them go off particularly quickly. Even after a 15-20 minute session the grip seemed consistent and predictable - I'm surprised they went "off" so quickly in your test.
It was the Dunlops that 'went off' although that is always a fairly subjective assessment and that has raised a few comments.