Vredestein knows that Grassroots Motorsports knows a thing or two about performance tires. And they know that our readers do, too. That’s why they came to us with a simple request: Find five readers worthy of a set of Vredestein’s latest performance tires, their Ultrac Vorti and Ultrac Vorti R. Over the next six months, you’ll be seeing feedback from these readers in the form of regular blog posts on our site.
Story and Photos by Spectro Racing
I am a bit of a tire snob. When given the chance to test a brand of tire that I had never heard of (nor could I really pronounce), I was enthusiastic for the opportunity, but skeptical of the tire. My disclaimer is this: while I did receive these Vredestein Ultrac Vorti tires for free, I am not being compensated in any way based upon what I write, and the following opinions are genuine.
My E39 M5 is a challenging test bed for tires. It weighs a hefty 4,000 lbs, makes tons of instant torque thanks to its individual throttle-bodied, naturally-aspirated V8, and has well-adjusted suspension geometry with a little help from Ground Control coilovers. Plenty of well-regarded (and very expensive) tires have perished from track and street duty on this beast. I generally have to run very high tire pressures to help stiffen the tire and prevent rollover onto the sidewalls, even with over three degrees of camber on my track alignment. The car benefits well from a stiff, responsive tire with high heat capacity. The 275/35/18 Ultrac Vorti has a load index of 99 (1709 lbs per tire), which is plenty even for my executive sedan.
I put tons of street miles on my M5 too, daily driving it and even driving it to and from track days. This year it completed the arduous Tire Rack One Lap of America, brought to you by none other than Grassroots Motorsports, which required 3500 miles of transit driving between daily track sessions for a full week. I have a very vested interest, then, in high-performance street tires that can survive track use while simultaneously being enjoyable on America’s oft-neglected streets.
That’s where the Ultrac Vorti is positioned: it’s a competitor in the Pilot Sport, Contact Sport, Pzero tier at 320 treadwear, built for powerful canyon-carving luxury cars, but not meant to fulfill the hardcore autocross niche like the RE71-R or Rival S “street” tires. I was not able to test the Vorti R version, which is also advertised as 320 treadwear, as it is only made in 19-21” sizes.
My expectations for this tire were quite low. I assumed that its performance would be mediocre; a result of cost-cutting measures to fit a price point: noisy, unresponsive, low grip, and unpredictable at the limit. Indeed, upon receipt they were surprisingly heavy, and the engineer in me lamented at the increase in unsprung weight. The branding on the tire itself isn’t anything remarkable. Personally, I’m glad to not have to pay for laser-etched velvet-feel finish, no matter how cool it might be parked at Cars and Coffee. The tread block design is also standard fare: big, wide tread blocks on the outside of the tire (they are not directional, but do have outside/inside) for increased grip at the limit, yet grooves plenty large to provide proper water evacuation for wet grip.
Once mounted on the wheels, I noticed immediately that they were very wide for their advertised size. I had run 275/35/18 in a few different brands on the 9.5” wide Style 65s, and none of them were as fat when mounted as the Ultrac Vorti was. I’d recommend ordering a bit small; a 265/35/18 would have fit perfectly on my 9.5” wheel. I could also feel the increased heft compared to the RE71R and the PS4S I had used before.
Despite the extra-fat fitment, they fit on the car without rubbing and looked great.
Remember those low expectations? They were unwarranted. Blown away, even. The first thing I noticed when driving them was just how quiet they are. I don’t mean they are quiet for a high-performance tire, or quiet for a budget tire. They are just quiet, period. Even though a narrower size would have provided for better sidewall support, I found them to be very responsive as well, deftly adjusting the direction of the 108” wheelbase sedan with immediacy and a low slip angle. They have the kind of turn-in that would be completely acceptable even at a tight autocross, without excessive tramlining or wandering on the highway.
I look forward to testing these under autocross and track day conditions to see how they behave at the limit, but I am now cautiously optimistic that they will impress. So far, my only real complaint is that they do seem to transfer a lot of vibration from the road to the car, which is a pretty unavoidable consequence of a stiff tire run at higher pressures. Otherwise, I’d say these are a real contender in the luxury performance tire market.
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