Pirelli Diablo SC3
Pirelli's Diablo SC rubber came into our test as one of the early favorites.
Easy to feel despite being blindfolded, Pirelli and its soft-carcass design weren’t hard to pick out of the group. Not crazy soft and almost scary like the Avons, but no doubt a mushier feel than the rest of the group. This a bad thing? Not at all, especially at Streets of Willow. Just different and something that takes a couple laps to get used to.
As mentioned, take a look at the slower Streets and there’s no question Pirelli is on top of the pile. No ties here, the SC3s laid down a 1:21.72, giving it a 0.11 gap over the Dunlops. And while this may not seem like much, consider the fact that at Willow Spring the top three tires are all within one thousands of a second, and suddenly a tenth feels like an eternity. So where does it make up the most time at Streets? No where really. It’s more a combination of small bits here and there, than one major area where it really shines.
The Italian shoes are fastest though Turn 3, Turn 7, Turn 9/10 and the drive onto the front straight, though only marginally in each. But the key is that everywhere else they are right in the mix, not losing much more than a tenth in any given corner, allowing it to capitalize on the areas where it does excel slightly. Once again, another example of how tightly knit the top four in this group are.
Here's a look at the corner-exit speed numbers at Streets.
As for corner-exit speeds at Streets of Willow, surprisingly it’s at the bottom of the pile coming out of the ultra-slow Turn 2 at 43.64 mph, nearly 5 mph down on the top ranking Avon’s (which is an anomaly in itself). As for the other slow spot in Turn 10, the Diablos ranked second at 45.55 mph, a mere 2 mph down on the Bridgestones. While this might not add up, it may simply come down to the use of different lines on different tires.
One advantage to the so-called ‘mush’ of the Pirellis is their ability shine on really bumpy tracks, which Streets no doubt fits into. The soft carcass soaks up a lot of the bumps quite well, even making up for some minor areas where suspension might be off. One could pick up on this right away and made the ride around the tight track much easier on the body as well as quicker.
Heading over to Big Willow the Pirellis really shined exit speed-wise, taking top honors coming out of Turn 8 at a lightning-fast 120.20 mph, some 2 mph up on the rest of the field. But just because it was quick exiting eight didn’t automatically make it top dog at the fast and flowing track, as the Pirellis logged the fourth-fastest time of 1:28.34. Though it must be noted it’s only 0.71 seconds of the top time – problem is, in this group, seven tenths of a second means almost last.
Taking a look at individual section times it’s easy to see the closeness, as there’s no one area that it loses major time, just fractions here and there, even sitting toward the top in a few places. More or less it’s mid-pack throughout the lap with the end result being less than a second off the pace, but still fourth position. But my personal impressions ranked it higher up the scale than the data did.
Speaking of scales, the Pirellis were second-lightest up front at 9-lb, 3.1-oz, yet the heaviest out back at 13-lb, 9.0-oz. Don’t let the tag of “heaviest” fool you though, as the lightest tire, the Avon, weights 13-lb, 1.1-oz; only a minimal 7.9-oz difference.
An angular tread patter graces the Diablo rubber, though like the rest of the group most of the tire is basically a slick with next to no groves.
No doubt these Pirellis ranked in the uppermost percentile for me when it came to rider comfort, as right out of the gate I could really push, and push hard. It may not have been top dog in the data world at the big track, but in my world it was right up there as one of the most confidence inspiring. This was one that surprised me when I found out which tire was which and how they did, as I was sure the Pirelli would be one of the quickest around both tracks.
With an ambient temperature of 105 degrees at Willow Springs, there’s a good chance heat may have adversely affected the tire. It does also feature a flatter and slightly harder-to-steer front profile, but when considering it was quickest around the tight and twisty Streets of Willow it all but rules this theory out.
We had only one minor complaint with the Pirelli when it comes to durability and that was rear tire life at Willow Springs. The hot temps and ripping-fast track put enough stress on the back that after lap three it went off slightly, slowing things down a bit. That said, it was by no means horrible and only dropped off by a tenth of a second. As for the tighter Streets, they only went faster as the laps progressed, going quickest on the final circulation.
The final verdict: I loved the feel and feedback of the rubber and they work both in the slow corners at Streets as well as the fast stuff at Big Willow. They may have been fourth at the Big Track but when one considers they weren’t even a full second back it puts everything back into perspective; this being the sheer competitiveness of the group (sans the Avons).
