Valve question

[Chaparral2f]

I'm porting my set of L98 heads. I know that they wimll take 2.00/1.56 valves. But I have found a good deal on a set of 2.020/1.60 Titanium valves.

I just don't know if they will fit the heads without major seat work. Has anyone had any experience with this? Also, what is your opinion of titanium valves? the set I have found will cost me less than manley sever duty steel valves. that's why I wonder what you think.

Joe

[Mudge]

Bigger isn't always better, too big can kill low lift flow, and shroud the valves for 1/2 or even more of thier lift duration. You will need new seats for sure, I went with 2.0"/1.56" for this reason.

 

Titanium? What for? If this is NA and less than a NASCAR RPM style setup, I wouldn't even consider it. I ran to 7k RPM and even for me titanium retainers was overkill, just something I wanted, but not neccessary.

 

Beyond the wasting of money possibility though, metalurgically speaking I am told its brittle, and may well not be a high duty application where its going to be slamming into valve seats all day long. I do know that it works as a rod (NSX), but its not quite the same thing.

 

Hopefully someone will have more input for you, talked to an engine builder about it? Coatings are still not a totally street thing to do, especially if your NA, but I would have liked to had coated valves, combustion chamber, and piston tops, but again thats more than is neccessary and costs money however nice it may be to have. If your just looking for light, then you could grab hollow stemmed stuff.

[Chaparral2f]

Thanks Mudge, I really appreciate the info. Actually, the main reason for considering titaniumn was that the price was right. (eight intake, and eight exhaust for $200) but the cost of new seats, makes the price nnot worth the trouble. that's why I keep coming here fro the straight dope!

Joe