Posted: 12/10/2014 3:00:00 PM EDT
|
I'm curious about the the +100 etc longer valve stems for an SBC. I'm gathering that the +4 valves are for the raised port heads with taller than normal spring and more valve lift.
So I'm wondering if its possible to use a +.400 titanium valve (del west) in a 190cc aluminium head or is there someone who can cut them down to +100 for a less demanding application? |
Came across some cheap Ti valves huh? To be honest, I've never heard of lopping the end off .400 long valves to use them in a stock or +.100 application. I don't have a set of Ti SBC valves here to look at but we used them before. DelWest makes good stuff. Wouldn't cutting them down .300 put you pretty close to the keeper groove? Also would you have to use hardened lash caps at that point? The seat material in the heads is something to check too. I thought that all the hotrods were running some sort of alloy (Boron or something exotic) to help soften the Ti valve closing impact. Also check stem diameter as I thought they made some smaller stem valves as well. This whole exercise might be a mute point. Another thing, now I might be way off as I'm getting up there  , but weren't you building a kit plane with SBC power?If so, I think I would pass on this deal. Unless you're planning on revving the nuts off this motor and putting all the rest of the hardware that warrants running Ti valves, I would stick with an unmolested, very good quality stainless. Maybe sodium filled if you thing you're going to be punishing the hell out of the exhaust side of things. And you have plenty of money for them. Either way it sounds like a lot of work for not much gain, not to mention some added risk involved with extra little parts adding into an already somewhat complicated valvetrain. But, if you're putting these into something that won't be at 7000 feet when it decides to shit the bed, go for it. Let me know how it works, I am genuinely interested.  Sorry I couldn't be more help.  |