[TheRetroGuy]

Summary:
Switching from Pilot 4S to Primacy Tour feels like getting a ~25HP performance boost due to lower rolling resistance. I'm astounded at the difference.

Detail:
I had the unusual opportunity to compare the Primacy Tour A/S back-to- back with the Pilot 4S. Unusual in the sense because normally, when I get new tires, I'm replacing old ones and there is little point in drawing comparisons between a brand new tire and a worn one. But this time my preferred tire installer screwed up... I originally ordered the Pilot 4S All-Season, but when I picked up my car it had the Pilot 4S summer tires. In correcting the situation, the tire shop said they believe the Pilot 4S A/S is being phased out because availability was spotty, so after some brief research I decided to go with the Primacy Tour A/S instead due to increased treadlife, quieter highway ride and of course availability.

So, my point of reference here is driving the Pilot 4S (summer) tire for a week and comparing it to the Primacy Tour A/S at exactly the same inflation pressure and tire condition (brand new).

Driving the car out of the tire shop lot, I was immediately amazed at how much faster 0-60 the car felt, compared to the Pilot 4S... I can only assume this is due to differences in rolling resistance of the tire design. To help illustrate the difference, I will say that I have taken trips with luggage that weighed more than 250lbs, and the difference in acceleration with or without the extra weight of the luggage was negligible. By comparison, the difference here between the Primacy Tour and the Pilot 4S feels more like 500+ lbs was trimmed off the car -- I am not remotly exaggerating with that statement. The difference was undeniable and honestly, quite jarring as I simply did not expect it.

In terms of the 0-60 performance, the Pilot 4S felt about the same as the Bridgestone LS100 OEM run flats that they replaced -- perfectly fine. Ride quality on the softer Pilot 4S was, of course, a night-and-day difference... Less vibration, lower noise simply a better overall ride.

Going from the Pilot 4S to the Primacy Tour A/S, as expected the all-season tire is a bit firmer, but still much better than the A/S run flats they replaced.

For spirited summer driving, there is no question the Pilot 4S offers a better experience, but for my own needs and driving style, a good all-season touring tire is a much better fit. The "acceleration boost" effect was an unexpected bonus that leaves me particularly pleased with the Primacy Tour A/S.