what kinda valves

[HEADSHOT]

id like to get some aftermarket valves. i plan on doing some fi in the future. do i need any machining work if i get over sized valves? what all is involved in selecting over sized vavles as well as the pros and cons..


thanks

[kdroberts83]

oversized valves will allow the head to flow more. As far as brand selection, I've always had good experiences with Supertechs. If you do go oversize you will have to have a machine shop do them, as they have to install new valve seats.

[HEADSHOT]

oversized valves will allow the head to flow more. As far as brand selection, I've always had good experiences with Supertechs. If you do go oversize you will have to have a machine shop do them, as they have to install new valve seats.

well im pretty much just going for a rebuild with a few upgrades. i plan to pull this motor several times while upgrading, sc, nitrous, etc. so i think ill save this mod for a little while down the road and just get me some cams

[I Hate Import Cars]

I'm assuming this is on a B Series? I know that once you go more than .5mm oversize with the valves, you start having to do a shit-ton more head work to unshroud the valves because with the pent-roof 4-valve head setup, you run out of room around the valves REAL quick. I'm building a 2.1 liter B Series at 12:1 with 150hp hit on the bottle, so I think I'm going to go with .5mm oversized valves, simply to move all that extra air and fuel. If you're running FI, I'd think you'd want to as well for the additional volume you'll be able to flow with them. But this is DEFINITELY somewhere where my experience is limited, so ask around to some people who have done it and had dyno runs before AND after to back it. I know the guys at AFI and at Full Race have done some pretty wild shit with their motors, so I'd imagine something as "elementary" as slightly bigger valves is something that they could point you in the right dorection on. Hope that helps a little.