Should I get bigger valves for NA B16A??

[thompy.mark]

Just wondering if I should be looking into getting bigger valves for my NA B16A build. Here's what I've got so far...

Buddyclub Spec 3+ cams
Double Valve Springs
Ti Retainers
Adj Cam Gears
Skunk2 Intake Manifold w 70mm throttle body (possibly upgrading to ITB's at some stage in the future if the wallet allows...)

Will also be getting some aftermarket extractors on there at some stage too, into a 2.5" exhaust.

The head is at the shop at the moment getting a port and polish, and while its there I want to get some stainless valves. Herein lies the question...Should I be going oversize, or stay with the stock sizing? I know the PR3 head flows reasonably well with the stock size, but I guess its really a matter of weighing up extra volume (oversize valves) against slightly higher air velocity (stock) which will then allow for better air/fuel mixing.

Thoughts/advice anyone??

 

[Hatchyspeed]

is your head port n polished?!? need a little more info then that one what to do i mean if ur heads got no valve angle job 3 / 5 ? u kno or its not port n polished i see no reason in going with bigger valves..

 

[thompy.mark]

The head is in at the shop at the moment, what I'm really after is:

Is it worthwhile getting larger valves (and the required head work such as port and polish, valve job etc)? Just re-read my previous post, it wasn't too clear sorry.

 

[powerdriverh22]

You might want to make sure you even have the valve/valve clearence to run larger valves. Don't just throw parts at an engine, know what you're doing and why you're doing it.

exactly. on h22's it is not possible to open both intake and exhaust valve openings with just s2s2's. most ive seen with those cams was .5mm on the intake side.

b16 heads flow well so i dont think you need the bigger valves.