engine and drivetrain aluminum valves

[johnpaul]

I’ve seen light weight valves on the internet but I was wondering how much power they will actually add because I'm going to be replacing my cam with a more lumpy one and I thought I might as well do some other upgrades while the engine is apart. So has anyone added the lightweight valves, I think they are aluminum.

[robspeed]

maybe titanium? would add no power by themselves, only good for race engines pulling 7500+RPM

[Lee]

You must certainly mean "titamun" valves. Expect to pay $150 per valve. They sometimes have thinner stems, which will require custom valve guides. They are a good choice if you CONTINUOUSLY rev your engine above 7000 RPM and expect to reach 8500 RPM on a regular basis.

[Rob7502]

There is one way that they will increase power on lower rev motors. You can run signifacantly lighter valve springs with out worring about float. The lighter the spring the less parisitic loss of power.

[pnwtii]

What about valves that are cut back? I always hear about people getting 3 angle or 4 angle valve jobs. Has anybody done this? I thought about combining this with porting and polishing for a little gain while still keeping the motor stock. Thoughts?

[Guest Anonymous]

Cut back valves are a bad idea. The stem transfers heat from the valve head to the guide and if you thin down the stem it will not transfer as well and overheat the valve heads.

[FL02]

High end valves and springs would allow for higher revs right? What would a valve job put the redline to? 2002 engines rev nice anyway, that it would probably be nice to have a rebuilt top end with Ti Valves, Springs and a hotter cam. I figure a new top end, a ported intake, a larger carb, and a header exhaust system would probably make an otherwise stock 02 really cook. Redoing the bottom end seems like more of a mission to me, and would probably need a machine shop to do it right. Anyone do a top end rebuild with better valves and springs? Would it be a waste not to do a full engine rebuild? Just curious.