Building a forged RB26/30 at the moment with a brand new RB26 head and I am aiming a reliable 700hp in a Datsun 240z.
I am booked in for TAW Performance to get porting done plus machine work for what I planned to be 1mm oversize Tomei Valves + supporting parts.
They suggested running "Poly Quad" arrangement for better low down power and torque (intake standard size and exhaust 1mm oversize for example) which creates a swirl effect.
Has anyone had any experience with different sized valves and can share their experiences?
Supporting mods:
RB30 Block, CP 9:1 forged pistons, Spool i-beam rods, RB26 GTR bearings, ARP mains, Nitto pump and collar, ARP 12mm GTR head studs, RIPS RB26 intake, 6Boost manifold + GT35r.
Thanks!