XRAY rates its touring car springs by spring constant "C" (N/mm) — higher C means stiffer — and the spring family follows the shock generation. The X4 and X4F use the low-profile XLP / XLP2 springs, while the earlier T4 generations use the long-running 4S springs. Linked springs go to that exact part at AMain.
X4 & X4F — XLP Springs
The current range from XRAY's official X4'26 parts list. The kit ships with the C=2.5–2.8 progressive up front and C=2.6 in the rear. The newest XLP springs are still working their way into retail channels — unlinked entries are XRAY part numbers you can order through any XRAY dealer.
Linear
| Type | C rating | Part # |
|---|---|---|
| Linear | C=2.5 | #308175 |
| Linear | C=2.6 | #308176 |
| Linear | C=2.7 | #308177 |
| Linear | C=2.8 | #308178 |
| Linear | C=2.9 | #308179 |
| Linear | C=3.0 | #308180 |
Progressive
| Type | C rating | Part # |
|---|---|---|
| Progressive | C=2.4–2.7 | #308164 |
| Progressive | C=2.5–2.8 (kit spring) | #308165 |
| Progressive | C=2.6–2.9 | #308166 |
T4 — 4S Springs
The 4S line is XRAY's long-running touring spring standard for the T4 generations, and remains widely available:
Linear
| Type | C rating | Part # |
|---|---|---|
| Linear | C=2.3 | #308274 |
| Linear | C=2.5 | #308275 |
| Linear | C=2.7 | #308276 |
| Linear | C=2.9 | #308277 |
| Linear | C=3.0 | #308290 |
Progressive
| Type | C rating | Part # |
|---|---|---|
| Progressive | C=2.3–2.6 | #308263 |
| Progressive | C=2.5–2.8 | #308264 |
Other Touring Car Spring Charts
Running something else? See the Tamiya TRF spring chart or the Mugen 1/10 touring spring chart.
Part numbers and kit fitment from XRAY's official X4'26 spare parts list. Some links above are affiliate links that support the site.
