A Tale of Two Summer Tyres/Tires

My PiP is a 2013 JDM, converted by Toyota for the NZ market. I bought it Feb 2017, as new apart from tyres and the odo reading (17,500 km). I replaced the Ecopia EP150's with more of the same, and have driven another 22K kms.
I have had excellent economy from the Ecopias, but indifferent tracking and cornering - after 2mm tyre wear the car steering often needed micro-adjustments, the sidewalls felt really soft. What to do?
Last year I bought a Hyundai Kona EV, like all Kona's, riding on Nexen Nfera SU1's. Ever heard of them? I hadn't either. In the 10 months I have had the Kona, I found the Nexens to be more than up to handling the Kona's substantial torque, very pleased with them wet or dry. A few owners found they lost grip too easily, but I'm a steady driver and I didn't experience that.

Along with Hankook and Kumho, Nexen is a major Korean tyre brand, and exports to 120+ countries. The company markets the Nfera SU1 as a Premium Sport Ultra-Hight-Performance tyre. It would seem that Hyundai has found this tyre to provide the best range on the Kona, in the same way that Toyota has always put Ecopias on the Prius models.
In January I had a lightbulb moment, when I realised that the Gen4 hybrid comes standard (here) with 215/45R17 tyres. I then found this size had been an option for the Gen3 as well, though not for the PiP or Prime.

The Kona Nexens are 215/55R17, so I immediately thought, maybe here is a replacement for the Ecopias. The 215/55 Nexen is 5% oversize - this would nicely take care of the excessively optimistic PiP speedo reading (+8kph over-read at 100kph).
Checking specs for rims raised no issues, same offset, thread size, a little different sized hub-centering spacer. The Kona wheel size is 5x114.3, the Prius 5x100. Could I get a multi-fit rim that would go on both cars, with just a hub spacer change? Yes, I could..

So that's what I have done, new rims and 215/55R17 Nexen tyres on the PiP (and Michelin PS4s on the Kona, but that's another story).

After a month I have found:
Handling, cornering and tracking are vastly improved. The PiP now handles like a modern vehicle. With my conservative driving I can get away with leaving the suspension as is..

At 100kph indicated, the PiP is now at 97kph GPS, at 50 GPS showing 52 on the speedo.

Relative noise testing (multiple tests) on smooth seal and coarse chip showed:
Ecopia 58dB smooth seal, 65dB coarse chip
Nexen (on the Kona) 56dB / 63dB split
Nexen (on the PiP) 56dB / 63dB split - no change
For interest, PS4 (on the Kona) 53dB/63dB split
So the Nexens are a little quieter than the Ecopia's.

Economy:
My typical highway economy on Ecopias invariably has been in the range 3.55L/100km - 3.85L/100km, from my usual cruise control @ 90kph (actual). So far the Nexens have been in exactly the same range. Given the higher gearing, I'm guessing that freeway economy at much higher speeds might be down a little?

Urban economy is something else. First, a 50km city run on main roads, round trip, speed limit 50kph, flowing traffic, but at least a dozen red lights. HV only. Trip kms and Trip fuel are accurately calibrated.



Next, at purchase Toyota suggested up to 26km EV range, and I tested that at the time - 25.9km. So that test again, after 3 years and 22K kms, now on the Nexens.


No complaints, those big tyres just keep rolling and rolling...!

Finally, wear looks good - see this post from a Kona owner who drives 1500km/week on business. 72,000km, no issues, down to 2.5mm.

My recommendation? I would buy these tyres again, certainly ahead of the Ecopias, at a good price of course. On the PiP I can't see any downside. And they are also available in 215/45R17, the standard prius size, though not in 15".