Just posting some info that I was always curious about and finally tested today. I am in the process of porting one of the sets of B1 heads I have for this years build and did a weigh test on a 2.300 stainless valve and 2.300 titanium valve.
Stainless valve 150 grams
titanium valve 105 grams
45 gram difference which at 7500 RPM equals more than I figured but it comes with a pretty high cost difference. Durability would be a big factor on valve spring and rocker life. I weighted a few things to give you an idea of how much 45 grams equals. This is one of my 1/4 inch shank double-cut carbide head porting burrs and it weights 40 grams.

I've read Ti valves are typically worth 800 rpm in valve train stability, and I would think a horsepower increase of some sort below that? I wish they were in my budget,,,,,,,,

Exhaust valves are 115 grams and 85 grams

John, I have no data to back this up, but wonder if the TI intake valves would offer a horsepower increase, while the exhaust might not do much other than increase rpm range and parts life? What got me thinking is the intake closing is critical, more so than the exhaust closing.

Not sure on that one Greg and the only reason I even have them is they came with a set of heads I bought years ago. Thinking I may start out with the older set of heads and stainless valves as this will be a learning year with nitrous

So if you add that carbide to the titanium valve it equals the weight of a stainless valve? Thats huge

My set of B1 M/C had 2.4 ti valves... $130 each for
the intakes

2/3 the weight.......2/3 the spring pressure required?

Instead of 300# on the seat, now only 210# ?

Not to mention the potential head flow increases from the reduced valve stem & guide size: typically 7 mm or less for Ti while equivalent size [head] SS valve will be >9 mm....

true but in my case the stem sizes are both the same. I still will probably flow them both just for the heck of it.

Isn't the weight of the valve only a part of the reciprocating mass that the spring has to control??

i.e. lifters, pushrods, rockers, retainers and locks.

Joe

So you would take 12.7oz off the intake (1.6oz ea.) side and 8.5oz off the exhaust (1.06oz ea.) side, just over 1lb 5oz that the valve springs don't have to move. Add light weight retainers and it would be a significant amount taken off.

Look at it this way, would you add that much weight to all your valves if someone paid you a couple hundred bucks?

I don't think looking at the total weight is a clear picture, each spring has only one valve among all the other parts to control.

I'll give you that at a certain performance level it becomes a no-brainer but under, say 7500 RPMs I don't know if you will see either performance or longevity issues.

Of course if money is no object......

BUT, if someone were to make the cost a little easier on the wallet, they'd be standard issue on my eng.

Joe

Even at 7500 there should be a longevity benefit as you can run a lot lighter tension spring.

I agree, the lightest springs to control a given RPM are what we should all have.
I would like to hear what Hughes or Barton and the like have actually seen in practice because of a change in valve weight alone.

Good topic...Joe

The best way to figure out what you need is to put a engine on a spintron. Very expensive and some engine builders have access to them. With this you can find out what valve springs pressures you can run, lifter bounce, how stable the valve train is at high rpm, ect.