Just curious,
and I know this is a nooby Q so just bear with me.

whats the need for highend valves? I understand valvesprings,
if you have an agressive cam, stock ones will get worn out.. and you'll drop a valve.. which = death.

but the valve itself..
whats the point of getting beefed up valves,
if a piston contacts a valve I dont see any chance of the valve surviving,
whether its made out of steel, aluminum, titanium, or whatever..

so why then?

thanks!

 

heres a thread i read last night check it out

https://honda-tech.com/zerothread?id=902687

 

Its not so much about strength. Primarily its about heat managment and a material than will minimize valve train mass. The valve is expose to combustion temps, so having a material than can handle the temps is very important. The lighter the valve, the less likely it is to float too. You also have wear issues between valve guide and valve, and the rocker and valve tip. This is why its good do have the valve tips induction hardened, or some other form of hardening.

 

Race only.

They are super cool. So light they feel like holding plastic.

 

aah,
ok I think I get it alittle more...

race only does seem about right to me,
I stil dont see much need for such a thing on even a really agressive street motor.

 

On 2 valve heads the valves can get big and heavy and require alot of spring to control it. A Ti valve here helps.

On 4 valve heads it's easy to have enough spring to control the valves even at 12k+ rpms.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Rocket &raquo;</TD></TR><TR><TD CLASS="quote">On 2 valve heads the valves can get big and heavy and require alot of spring to control it. A Ti valve here helps.

On 4 valve heads it's easy to have enough spring to control the valves even at 12k+ rpms.</TD></TR></TABLE>

you mean 2 and 4valve per cylinder??

 

You can raise your compression with flat face valves, and they are lighter = a little less friction

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Power Rev Racing &raquo;</TD></TR><TR><TD CLASS="quote">You can raise your compression with flat face valves, and they are lighter = a little less friction</TD></TR></TABLE>

How are they lighter? Is the inside of the face or the valve filled with a pocket of air and not a solid pice of material? How does friction come into play in your answer?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EKhatch &raquo;</TD></TR><TR><TD CLASS="quote">How are they lighter? Is the inside of the face or the valve filled with a pocket of air and not a solid pice of material? </TD></TR></TABLE>

Lighter will mostly depend on what the valve is made of.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">How does friction come into play in your answer? </TD></TR></TABLE>

friction against the valve guides. lighter valve = less friction. although don't know how big of a deal this is.

 

[QUOTE=kommon_sense]

Lighter will mostly depend on what the valve is made of.
QUOTE]

material for material, it will be lighter.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kommon_sense &raquo;</TD></TR><TR><TD CLASS="quote">

friction against the valve guides. lighter valve = less friction. although don't know how big of a deal this is.</TD></TR></TABLE>

how does the valve's inertia affect friction?

besides surface area and texture, I don't think it matters.

 

have you doods checked out the new valves from ferrea? they have hollow stem and sodium filled versions for extra lightweight

 

it sounds cool when you say "i got titanioum valves yo!!!!"

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kommon_sense &raquo;</TD></TR><TR><TD CLASS="quote">

Lighter will mostly depend on what the valve is made of.

</TD></TR></TABLE>

That is pretty obvious, he makes the statement that flat faced valves are lighter or at least that is what it sounds like he is stating.

I still don't see how lighter valves have less friction on the side of the valve guide. Unless you are stating this because the guide is at an angle from verticle and the weight to the side is different which can be argued different ways.

 

Using a Ti valve would allow you to run a softer valve spring, which in turn decreases frictional loses. Less friction means increase in horsepower/response.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by xtrac1 &raquo;</TD></TR><TR><TD CLASS="quote">
Using a Ti valve would allow you to run a softer valve spring, which in turn decreases frictional loses. Less friction means increase in horsepower/response.</TD></TR></TABLE>

For some reason I thought he was referring to the valve guide. What I get from your statement is that there will be less friction on the rocker pads, valve tips, cam lobes, etc.... Which makes a hell of a lot more sense.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by EKhatch &raquo;</TD></TR><TR><TD CLASS="quote">I still don't see how lighter valves have less friction on the side of the valve guide. Unless you are stating this because the guide is at an angle from verticle and the weight to the side is different which can be argued different ways. </TD></TR></TABLE>

unless a valve is completely vertical there is gonna be friction and friction depends on the mass/weight of the valve and the coefficient of friction between the valve and valve guide. So a heavier valve will have more friction. I'm not saying that the different is significant... Just saying that there is a difference.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kommon_sense &raquo;</TD></TR><TR><TD CLASS="quote">

I'm not saying that the different is significant... Just saying that there is a difference.</TD></TR></TABLE>

Gotcha.

I just wasn't sure that I was understanding you correctly.

Thanks

 

Just some food for thought,

There are some volkswagen valves (passat 1.8t in particular) that are hollow and have sodium gas i believe that turns in to liquid at high temp and cools the valve down, i have a picture of a broken one some where if anyones interested

70 bucks a piece from the dealer. (and thats times 20)

needless to say valve jobs on VWs can get pretty expensive.

-sander

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by kommon_sense &raquo;</TD></TR><TR><TD CLASS="quote">unless a valve is completely vertical there is gonna be friction and friction depends on the mass/weight of the valve and the coefficient of friction between the valve and valve guide. So a heavier valve will have more friction. I'm not saying that the different is significant... Just saying that there is a difference.</TD></TR></TABLE>

I have a feeling friction wear from valves moving, wearing down the head is something
that is so rare its hardly worth mentioning..

could be wrong though.