600+ WHP Nissan 300ZX Twin Turbo // Solid State Relay Fuel Pump Upgrade & Dyno

This video covers the full engine reassembly, fuel system overhaul, and dyno tuning of a twin-turbo Nissan 300ZX. As many in the VG30DETT community know, maintaining consistent voltage and fuel flow is a critical challenge when pushing for higher horsepower, and upgrading to a pulse-width modulated (PWM) system is a game-changing solution to overcome the limits of factory wiring and traditional relays. Seb takes you through the step-by-step process of resolving a cylinder five ring issue, dropping the freshly built longblock back in, and wiring up a Solid State Relay (SSR) to precisely control a high-flow Walbro 450 fuel pump via Haltech. A major focus of this video is the execution of the fuel system upgrades. While adding big power is the goal, achieving a clean, reliable, and professional result requires meticulous wiring. Seb demonstrates how to run a brand-new bulkhead fitting, a heavy-duty 10-gauge dedicated ground, and an SSR integration to eliminate electrical resistance and voltage drops. In high-performance twin-turbo applications, the integrity of your fuel pump wiring is just as important as the hardware itself to ensure consistent fuel delivery, prevent fuel tank heat soak, and maximize engine safety. Build Features & Highlights: -Engine Platform: Fully refreshed VG30DETT featuring upgraded pistons, rods, cams, and Jim Wolf Sport 700 Gen2 turbochargers. -PWM Fuel Control: Moving from a standard digital switched output to a digital duty cycle table via Haltech to prevent overdriving the fuel pump at idle and cruise. -Precision Electrical: Brand-new bulkhead fitting at the factory assembly tank top and a 10-gauge dedicated battery ground circuit to prevent continuity issues. -Specialty Z Standard: We don’t just "wire it in"—we focus on frequency tuning, solid grounding, and optimizing the fuel delivery map to get the most headroom out of the injectors. In This Video: -Overview of the VG30DETT engine build and cylinder 5 ring repair -Solid State Relay (SSR) installation and 10-gauge grounding technique -Haltech ECU programming for Pulse Width Modulation (PWM) duty cycle -control Base fuel pressure testing and idle duty cycle adjustment -Full dyno pulls up to 21 PSI, hitting the limits of the Nismo 740cc side-feed injectors Follow Specialty Z: For the best in VR30 tuning and performance, visit us in Simi Valley.📈 Watch the pulls. ⚙️ Hear the turbos. 🔥 Feel the passion. 🔧 Expect Many DYNO pulls, behind-the-scenes tuning action, and plenty of car culture 👉 Subscribe for more insane builds, turbo setups, and behind-the-scenes content. 💻 Shop Specialty Z Products All of our in-house performance parts are available on our official website: www.specialtyz.com . For questions or custom inquiries, email us directly at [email protected] . 📲 Stay Connected Follow us on social media for updates, behind-the-scenes content, and more: Instagram: @specialtyz Facebook: Specialty Z 👍 Support the Channel Don’t forget to Like, Comment, Subscribe, and Share to help us bring you more Nissan & Infiniti content! #Nissan #Infiniti #GTR #Skyline #NISMO #370Z #350Z #300ZX #TwinTurbo #JDM #Racing #Racecar #Automotive #Z32 #Z33 #Z34 #R35 #R32 #R33 #Datsun #Performance #CarCulture #CarSpotting #2024 #NissanZ