Ok, here's a question for you guys -

How durable are Ti valves in a street application? My car rarely sees the track at the moment, but I give it pure hell regularly on the street (I know, I know). Shifts are at around 6800, and it makes excellent power right up to the shifts. I've been thinking about Ti valves simply because they are much easier on the springs, but it represents a substantial investment to call del-west or Manley and I have no prior experience with Ti.

Your thoughts?

Dave C.

 

Titanum valves will wear quickly.They cost to much to replace every 5,000 miles not to mention the seats.
Unless you are shifting above 8000 they are not needed.They make springs that can control the valve mass anywhere under that.
Intakes are about $600.00 for 8 and I don't trust them on the exhaust especially if you use N2o they don't seem to take the heat well.You can coat them but a set of $800.00 exhaust valves is un heard of.

 

I have a feeling the LS7's Del West valves had a hand in this thread. Those heads have put some thoughts into my head also...

Edit: the head on my shoulders, but that could lead toward strange things in my cylinder heads also

 

no need for Ti at that RPM

 

Thanks for the info. I really didn't know they were that much of a wear item. My thoughts on it were to extend the rpm of the motor to the middle to upper 7K range if the valves would last for any decent time, but 5K miles simply isn't enough to justify the cost. No wonder ebay is littered with ex-nascar valves! Sounds like they are all used up by the end of the race..

Thanks again for the replies fellas. I'll move on to the next set of ideas..

Dave C.

 

The LS7 only has a 7000rpm redline. Why did they use titanium valves?

GM seems to think that very lightweight valves are a very good thing. They used hollow stem valves in the LT4 & LS6, then the Ti valves in the LS7. They build these engines with the intention of running 100k miles.

I have a feeling that everybody that says Ti valves wear out are used to seeing them on solid lifter motors with very aggresive ramp rates at high RPM. I asked several people at my school about running Ti valves in a hydraulic roller setup with a 7000-7200 redline. Nobody had ever heard of anybody doing that.

Has anybody on here ever seen a combination like that?

 

AdioSS raises a good question. I'm concerned about this comment about quickly wearing out Ti valves. I don't mean to hijack the thread but I have a set of Nascar-style 4.3L V6 aluminum race heads that I'm probably going to be putting into a street-strip warrior V6 Fiero in about a year (when we just can't go any further with the Vortec heads that are on it now). The Nascar heads have Ti valves in them right now and I was PLANNING on using them.

1. They're going to wear out quickly if this thing sees any street duty? How much? Couple hours a weekend doing pickup races on the street for a season going to kill them? Street/strip kinda vehicle.

2. When the valves wear out I assume they take the seats out with them?

3. Should I just get some stainless valves in the same diameter (2.08/1.60) and put them in? Would the existing seats be compatible with stainless or are they "soft" too?

 

Don't see an issue with wear.

I believe the Infinity Q45 comes from the factory with titanium valves. That should say a little something for the durability.

If the concentricity is off, you're going to impact the life of your valves/seats... but that is regardless of valve material.

You DO have to run beryllium copper seats with Ti valves or they will not transfer heat like they need to. Other than that, it's just a question of gains per dollar and this scores real low on that scale.

Endurance racing is one area where they'd be a no brainer decision but we may not be talking the same game when street engines are the focus of discussion.

-Mindgame

 

Well, I can tell you that MY interest in these had nothing to do with the fact that they are being used in the LS7. I'm interested in the benefits of the lighter assembly being easier on the springs. There have been a few questions raised on this though that I didn't think about (specifically about the LS7 application). I think I may give del-west or Manley a call and find out what they think about a 7K redline with Ti valves in a mostly street application. The only experience that I DO have with them is on a 406 ia a friends rail, but that thing spins to 9K on alki. Kinda apples and oranges.

Are there any other OEM's that use Titanium valves a production engine? Might be some good info to be gleaned from the them as well if they are out there...

Hmm. And I thought I was done with this idea

Dave C.

 

CCCC...

Check into Ferrea's new hollow-stem valves if you're serious about lightening things up. They even offer a sodium-filled exhaust valve now. That'd be the ticket... and it'd save you a few bucks over Ti.

But you are right... valvetrain control is the name of the game and "lightweight" is a step in the right direction.

-Mindgame

 

I have run 2 sets of Dell West valves in my Ford and they have to be replaced every year.They have a groove around them that can't be cut out without reducing the dia. and the seats are pounded out bad and have to be replaced.
The PASSENGER cars you are talking about aren't running 800+ pounds on the nose and 300lbs on the seat and probably have a cam with soft closing ramps and not near as much lift.
Go ahead and try them it's only money,they may work for you.The hollow stem and the filled valves sound like a better option and reduced dia stems(but that is a high wear item too)
For street duty they are not needed.

 

when it comes to the ls7 i think gm almost had to use them to control the intake valve and make the lifters live by using light # springs .600 lift and a 211* lobe using a 1.8 rocker doesnt inspire any semblence of gentle in my head. especially when you start taking it to 7k rpms. hell thats a pretty good redline for a stock small block valvetrain setup in anyones book. but about the ls7 i havent seen any maintenance schedules yet and who says gm didnt say "they have to be changed at x miles to keep the warranty" when you get into some pretty nice high end parts sometimes maintenence becomes ungodly costive. anyone remember the price of an oil change in an enzo. its like $700 iirc. not that you care if you have that car its just a good example.

hell if you want to get up into the mid/high 7's for rpms just pony up the money for a nice solid roller setup... thats where i'd spend it, despite popular belief and wives tails they are fairly livable on the street if you dont get carried away.

 

A 211* lobe beats the hell out of a 270* lobe@868 lift with 2.0 rockers.

 

Not hardly. From what I hear they plan to build up to 8000 LS7s which are production engines which have to meet all the high mileage emissions and durability requirements without replacing internal engine parts. The Z06/LS7 also doesn't pay a gas guzzler tax...probably the only 500 hp production car which doesn't.

Ti inlet valves, hollowstem exhaust valves, lightweight retainers, and perhaps beehive springs certainly keeps the valvetrain weight to a minimum. Combining that with relatively mild valve timing means lower spring pressure and longer life. It's Catch 22 in reverse.

The OEM problem is usually money, but the LS7 has a big enough budget to affort the Ti parts. Probably the same deal with the Ti rods; it keeps the reciprocating mass lower so there's less load on the crank at 7000.

IMO, using the Ti parts is good for the LS7's image, so the extra cost also helps marketing.

 

Just thought Id point something out. If you just want lighter valves to be easier on the springs, and you spend at least $1200 on a set of valves, wouldnt it be better to just replace the ~$200 valvesprings 6 times? Granted if the engine would benefit from lighter valves it would make sense from a performance standpoint, but at 6800rpms now, Im just taking a guess here and saying that you probably would not have any cam left past that where lighter valves would not extend the RPMs but maybe 1-200, and also another guess here but if you are using stock computer you only will get 7000 no matter how big the cam and light the valvetrain. I like Brets advice in picking up hollow stem Ferreas for probably 1/4th the price.

Forgot what I read, it was Mindgame that said the above