Titanium Valves In A Daily Driver

[defrag010]

type 4, did you ever finish this project? If so, what were the results?

For the people who were talking about copper impregnated powdered metal seats in the LS heads -- have you looked into the SAE863 alloy?

[Piledriver]

I can't find the original post, but it was something about copper infiltrated powder metal valve seats. One of the big companies makes them for Chevy, and only sells them to Chevy from what I read.

That's what I remember, sintered steel w/copper infused.

Patent looks like it's expired.?

http://www.patentstorm.us/patents/4724000/claims.html

[xanadu]

What is the valve seat material? It can't be that expensive, after all you can buy a set of LS7 heads over the counter pretty affordably. That obviously doesn't mean the material is easily available though!

I've read that other production engines with Titanium valves are using very high tech hard coatings, on the titanium, to make them last.

I don't see any sign of these high tech coatings, being available on any titanium valves, from the typical racing aftermarket valve companies. They appear to assume that the only application is short term racing with Beryllium Copper valve seats?? Would Beryllium Copper valve seats hold up to any kind of serious mileage?

I haven't seen these unbotainum valve seats.... and i've had three sets of LS7 heads float thru the shop in the last month. (yep they are that light)

The LS7 stuff has a powder metal seat and guides and Ti valves from Del West. The Del West valves have a lash cap which is a big no no IMHO.

As for coatings the stock LS valves have a PVD coating on the heads of the valves. (My guess is a TiAlN)

You could use a variety of coatings depending on the hardness level you wanted. Titanium nitride is a good caoting for valves..... "(TiN) (sometimes known as Tinite) is an extremely hard (~85 Rockwell C Hardness or ~2500 Vickers Hardness or 24.5 gigapascals),[1] ceramic material, often used as a coating on titanium alloy, steel, carbide, and aluminum components to improve the substrate's surface properties." You see TiN on a lot of drill bits and end mills.

TiAlN, TiCN or CrN are also good choices, I've seen Cup valves with TiN on the heads and from what I hear wear is almost nil during a race.

Bret

Curious as to why the lash caps are a No No in your opinion.

[928S]

Don't have a lot of time to give a detailed answer but I know for a fact the LS7 valves are CrN and this is used a lot in Nascar, sometimes they put DLC over the top of the CrN. I am also doing a Porsche engine and will use DLC coated valve stems but not on the valve where the seat is. I hope they are not Be seats? I did try to read everything but may have missed it. They will not last with unleaded fuel.

Be is generally not used anymore in Nascar due to the unleaded fuel, moldstar 90 is popular as are the seats made by CHE which is what I am going to use. Stealth Technologies also make good seats for use with Ti valves, they are expensive though.

It will be interesting to see the flow numbers, mine has gone from 211 cfm @0.500" to 281 cfm but I know there is more to be had and I hope to get to at least 300 cfm, the port has increased in size by close to 11% My capacity has gone up 25% and the revs up close to that also, if your capacity is not going up I would not make the port any bigger or not substantially bigger anyway.

How much spring pressure did you have?

Greg

[PackardV8]

What is it about BeCu seats which do not like the combination of unleaded fuel and Ti valves?

thnx, jack vines

[928S]

The BeCu seats don't like the unleaded fuel, that is what I read in RET and and Mike at Del West told me this also. There was a lot of failures apparently, very rapid wear, maybe done to lack of lubrication?

Greg

[Momus]

Full coverage CrN is the universal standard now. It's wonderful.

Hard bronze is probably preferred seat material but the stuff seems to work fine on ferrous as well.

[Piledriver]

How do the "copper filled" sintered iron seats work out with Ti? (Mahle etc)
Tried to find those for a 3.6 subaru 6 awhile back to replace the junk factory seats (deep pitting at low liles common) but none in right size at the time.
Figure the better cooling seats combined with the thermal conductivity of the ti world be a great combo on a boosted motor.

[frnkeore]

Hard bronze is probably preferred seat material but the stuff seems to work fine on ferrous as well.

What alloy are you calling hard bronze?