Brian Crower 30mm Intake Valves for D16Y8/D16Z6

Brian Crower 30mm Intake Valves for EG/EK/Del Sol (D16Z6/D16Y8)

Every bit of air your D16 burns has to get past the intake valves. They're the last thing standing between the port and the cylinder, so their size and shape set a hard limit on how much the engine can breathe at high RPM. On a stock engine, the factory valves are fine. Once you've ported the head, added a cam with more lift, or added boost, the intake valve is often what limits how much air gets in. Push more air at a valve that can't let it through, and you've just spent money on parts that can't do their job.

These Brian Crower 30mm intake valves are made for a D16Z6 or D16Y8 head that's being built for more power. On their own, valves won't add much. They're one piece of a head build, and the gains show up when the ports, cam, and valve springs all work together. If your head's going to a machine shop for porting or a valve job anyway, this is the time to put them in. If the engine's otherwise stock, you won't feel a difference.

Why Valve Shape Matters

Air doesn't just pour through the opening around the valve. It has to bend around the head of the valve and the seat, and how smoothly it makes that turn decides how much actually gets into the cylinder. The shape of the valve head, the angle where it meets the seat, and how smooth the back side is all affect flow, especially at low lift, when the valve is barely open. Brian Crower designs these valves to flow well through the whole lift range, so you get the most out of a ported head instead of losing it at the valve.

Install Notes

New valves always mean machine shop work. Have the seats cut to match, check that every valve seals, and measure installed spring height on each one, since a new valve can sit at a slightly different height than the old one. If 30mm is bigger than your factory intake valve, the seats and the throat of each port also have to be opened up to fit it, so plan that into the head work. Check piston-to-valve clearance with your cam before final assembly. While the head's apart, replace the valve stem seals, and consider new guides and springs if you're adding lift or RPM.

Fitment

• 1992-1995 Honda Civic EX and Si (EG) - D16Z6
• 1996-2000 Honda Civic EX (EK) - D16Y8
• 1993-1995 Honda Civic del Sol Si (EG1) - D16Z6
• 1996-1997 Honda Civic del Sol Si (EG1) - D16Y8
• Intake valves only