Big Valves

(Difference between revisions)

Revision as of 03:54, 11 April 2013

Stock valves for A12 engine are 35 mm intake, 29 mm exhaust. You can fit the A14-size 37mm inlet/30mm exhaust. And valves up to 40mm have been fitted for ultra high-RPM use.

Overview

The 40s may require relief/flow notch in the side of the cylinder wall?

Feral

Feral used 40mm steel Inlet valves, tuliped and swirl polished, with 35mm Exhausts steel polished.

42mm Valves

42 mm intakes are perhaps the limit for fitting to A-series cylinder head.

Dual Valve Springs

Large valves work best at high RPM. When revving over 6000 RPM, dual valve springs are called for.

Triple Valve Springs

Photo Index

Big Valve

Valve Spring