If you’re a pistonhead, you have people. You know, Nick the mechanic or Joe the dyno. I got a tire guy: Ernie Bello. Bello tires is a performance car hangout, with all the right equipment for mondo mods and a lounge, decorated with a map of the Nürburgring, stocked with car mags, ice cream and kick-ass Cuban coffee. When my sports car needed new tires I clicked on Tire Rack for price and advice. I then went to Ernie. Hey Ernie! Whaddayathinkin here?
For a long time, Ernie was a Toyo guy. Ernie’s now nuts on Nittos. Trusting Ernie’s advice, I went with the Nitto Invo. I’ve now driven over five thousand spirited miles on the shoes, including a 1500 mile trek to the BMW factory in Spartanburg, SC.
Like many high performance cars, my BMW boasts staggered wheel sizes: 225/45 17” wheels in the front, and 245/40 17” wheels in the back (on the stock rims). This setup improves handling, but eliminates front-to-back tire rotation. That means shorter tire life; the rears suffer from my aggressive driving style, while the fronts stay ahead of the game.
Bottom line: I got great G’s on the track, and then spent them down at Ernie’s replacing the rears on a regular basis. Readers of my reviews will not be surprised to learn that I wanted a tire that wasn’t overly expensive, offering reasonable wear life, without sacrificing performance. I was pleased to learn that the Invos are non-directional; I can rotate the rubber side-to-side to balance wear. Somewhat.
The Invos are classified by Nitto as ultra-performance street tires. Translation: they’re designed for both wet and dry traction– without sacrificing ride comfort and noise suppression. Competitors include the Michelin Pilot Exaltos, the General Exclaims (previously reviewed), Firestone Firehawks and Bridgestone Potenzas.
The Invo has a unique design. The tire incorporates standard tread design with a three channel-deep wide-rib, located on one side. Nitto claims that combining an inner rib with two circumferential grooves improves wet weather performance. The rest of the tire consists of a Silica-reinforced tread compound, variable pitched grooves and large inner and outer contact patches (for improved dry handling).
The Invos come in sizes ranging from 225/45 17” to bling-sized 275/25 24” monsters. The tires are “Z” rated; good for speeds over 149 mph. But they’re also limited by a “W” rating, which pegs the maximum safe speed at 154 mph. The 17” tires I purchased have a 91 rating for load, which means a maximum load per tire of 1356 pounds in the front. The larger rear Invos support over 2000 pounds per tire, for a 5000 pound total.
Nitto warrants Invo tires for uniformity problems for sixty months after purchase– subject to rotation every 3500 miles. As expected with performance tires, no mileage warranty is offered.
Without sophisticated equipment, testing tire on a scientific basis is impossible. As to mileage tests, one requires either many years of patience or a machine to artificially add mileage. Having neither, I can only provide my subjective analysis of the tires based on years of experience.
The other issue with tires is the trade-off between comfort/noise/longevity versus performance and traction. Tires that lean toward performance usually have comfort and noise issues. Softer, more compliant tires aid comfort but lose performance capabilities.
I tested the Invos for four characteristics: noise, comfort, dry traction and wet traction. The easiest to measure was the Invo’s noise level. I found the tires extremely quiet, with little noise intrusion with the vehicle’s top down, and none with the top up.
Comfort was harder to measure; the BMW M Roadster is already a somewhat harsh vehicle to start. Compared to the stock Michelin Pilots, I found no change in the comfort level with the Invos installed. I lean to a harsher ride on a sports car and the Invos did not make the ride any worse.
The fun part of testing is pushing tires to the limit
on the street in simulated track tests in open lots. All tests were performed with the traction control turned off.
I tested dry handling by completing high speed turns and simulated slaloms. I found traction to be substantial, with the car failing to break away. This made reasonable drifting impossible. I also tried several panic stops, inducing ABS vibration. Again the Invos functioned very well.
Wet traction was only slightly worse with slower slalom speeds and longer braking. I never felt a loss of control. I’d trust these tires (though my M never sees rain, the spoiled bitch that she is).
With the install, I paid $600 for all four shoes at Bello Tires. Not the cheapest option, but well worth the price and competitive with the other tires mentioned above. Now if I can only get 20k miles on them!