GSC P-D Nissan RB26DETT/RB26 Cylindrical Valve Spring Kit

GSC Power-Division Cylindrical Valve Spring Kit with Ti Retainers — Nissan RB26DETT (5775)

A complete single-spring valvetrain kit for the RB26 — 24 titanium retainers, 24 cylindrical valve springs, and 24 chromoly valve spring seats. Everything for both banks.

Sized for a specific window. GSC positions this as the spring kit for a daily driver running an S1 or S2 cam profile that keeps boost below 32 psi and RPM below 8,500. If your build lives inside that envelope, this is the right kit. Past it, the conical spring kit is where you go.

Spring rates: 80 lbs at 1.319" installed height, 199 lbs at 0.905".

The manufacturing detail matters more than it sounds. The springs are nano-peened and batched according to seat pressure within GSC's spec, so every spring in the set is matched. The titanium retainers are CNC machined to tolerances and repeatability GSC claims are unmatched — and the point of both is consistent seat pressure across all twelve cylinders' worth of valves. Uneven seat pressure across a head is how you get one cylinder that floats before the others.

Round wire springs built with the same attention to detail as GSC's beehive kits.

Titanium retainers cut reciprocating valvetrain mass, which raises the RPM at which the valvetrain goes unstable and reduces the load the spring has to control.

Do this while the head is off. Springs and retainers are a head-apart job, so if you're already in there for valves, guides, or a valve job, this is the time.

Verify your cam profile before ordering. A spring that's wrong for the lobe either floats or coil binds, and both end the engine.