GT Radial SportActive 2 vs Star Performer Interstellar
Ahead in each discipline
The GT Radial SportActive 2 and the Star Performer Interstellar have met in one independent test so far, and the SportActive 2 finished ahead. The SportActive 2 was stronger in dry and wet.
Every measurement, side by side
Both tires' figures from the one test that ran them together, on the same car, in the same size, on the same day. The bar grows towards the tire that did better.
| Measurement | SportActive 2 | Gap | Interstellar |
|---|---|---|---|
| Dry SportActive 2 ahead | |||
| Dry Braking ft | 118 | 4% | 123 |
| Wet SportActive 2 ahead | |||
| Wet Braking ft | 104 | 5.9% | 111 |
Braking distances and lap times are better when lower; speeds, wear and grip figures when higher. A test's figures are its own: sizes, cars, surfaces and temperatures differ from one to the next, which is why the averages here are only ever of tests the two tires shared.
Head to head in 1 test in 2025
Each row is one published test in which both tires ran on the same car, in the same size, on the same day. The line is the whole field, winner on the left.
| Test | SportActive 2 | Field | Interstellar |
|---|---|---|---|
| 2025 Summer Tire Test Shootout | P21 of 52 | P34 of 52 |
SportActive 2 vs Interstellar: your questions
Is the GT Radial SportActive 2 or the Star Performer Interstellar the better tire?
The GT Radial SportActive 2 and the Star Performer Interstellar have met in one independent test so far, and the SportActive 2 finished ahead. On the Tire Reviews Score, which weighs every test and review we hold, the SportActive 2 scores 8.3 and the Interstellar 6.7 out of 10.
Which is better in the wet, the SportActive 2 or the Interstellar?
The SportActive 2 led 1 of the 1 wet measurements the shared tests recorded.
Which is better in the dry?
The SportActive 2 led 1 of the 1 dry measurements the shared tests recorded.
What do owners say?
Owners rate the SportActive 2 87% from 8 reviews; the Interstellar has no owner reviews yet.
Are they available in the same sizes?
The SportActive 2 is made in 57 sizes (16 to 22 inch) and the Interstellar in 23 (16 to 19 inch). 14 sizes are available in both. On the EU label the SportActive 2 is graded A for wet grip and D for rolling resistance in most sizes; the Interstellar B and C.
More comparisons with these tires
Run either of these?
Your review is the part of this page no test can supply: how the tire wore, how it aged, what it was like in the rain in year three. It takes about five minutes.
Where this data comes from
Finishing positions and measurements are transcribed from each published test. A test only counts here when both tires ran in it, so every figure was recorded on the same car, size and day as the one it is compared to.
About the TR Score
The Tire Reviews Score rates each tire out of 10 from every independent test result and vetted owner review we hold, so two tires can be compared even before a test has run them together.
Who does the testing
Every test published as a Tire Reviews test is run by Jonathan Benson, who has been testing tires independently since 2007.