The ideal all-rounder for high-performance street use with occasional track days. Naturally aspirated with a stock cam — triple groove stainless valves provide excellent retention without over-engineering.
Key Selections
Triple groove stainless valves — best street/track balance
Dual valve spring kit with steel retainers
Stock cam profile — factory-spec valve spring rate
H-beam connecting rods for high-RPM durability
Why Performance Spec?
Street & Track Days + naturally aspirated + stock cam is the only combination that fits within Performance Spec tolerances — no additional heat or spring-rate demands require an upgrade.
Recommended Configuration
Race Spec
Race Spec Build
Configured for competitive performance with Inconel exhaust valves and titanium retainers. Optimised for naturally aspirated with a mild-lift cam — the right spec for sustained high-RPM track operation.
Key Selections
Triple groove stainless intake with Inconel exhaust for track durability
Dual valve spring kit with titanium retainers
Stock cam profile — optimised spring rate
I-beam connecting rods for sustained high-RPM operation
Why Race Spec?
High Performance Racing demands Race Spec's Inconel exhaust valves and titanium retainer spring kit for sustained competitive operation beyond Performance Spec limits.
Recommended Configuration
Extreme Spec
Extreme Spec Build
Maximum-output configuration with full Inconel valvetrain, beryllium copper guides, and high-lift titanium spring kit. Built for forced induction with a high-lift cam — drag, time attack, or any application demanding absolute reliability under extreme conditions.
Key Selections
Full Inconel triple groove valvetrain — maximum heat resistance
High-lift titanium retainer spring kit for aggressive cam profiles
Forced induction spec — PTFE extreme stem seals
Billet H-beam connecting rods and fire-ring MLS head gasket
Why Extreme Spec?
Forced induction combined with a high-lift cam creates thermal and mechanical loads that exceed Race Spec limits — Extreme Spec's full Inconel valvetrain and beryllium copper guides are required.
