material for exhaust valves
 

Well, I decided I'm gonna run water injection on my close to stock LS motor build, I would call it budget but if you were paying for all teh stuff i'm doing you'd be broke. having your bestfriend own a machine shop is a great thing

well as many may know the higher temperatures on the exhaust valve wen running water injection could be an issue with stock valves so I wanna look into making a set of billet steel or billet stainless exhaust valves.

the valves but will be machined out of rod stock, but what should they be made out of? stainless or regular steel? I'm leaning towards stainless because of teh amount of steam flowing over the valve

what are stock valves made of anyways?

Re: material for exhaust valves
 

Ok this is like that 5th thread you made with stupid machining questions. >:( Just becuase your best friend owns a couple of machines doesn't mean anything you need you can machine and its going to be cheap or even good. ::) I did a part today at work and held a 0.0005 tolerance and I still wouldn't want to make all that dumb ----. The time, money, and tooling you need to invest is not worth it for exhaust valves, head bolts and all that other dumb ---- that costs under $100 to buy. :3


Before you make your next thread asking how to machine a muffler or a headgasket, ask yourself, "what is the likelyhood of me actually making this part" :3

Re: material for exhaust valves
 

thanks for your concern whitey, but i was just wondering because the shop owes me a bunch of cash and i figured that i could get paid in work, ooh and its not a small shop with a few machines, over 5000 square feet, 18 machinists, 3 brand new HAAS CNC's...

as for the hhead bolts, that was to prove buddy wrong and i was just wondering about valves, because well i dont wanna be gehtto and too (whitey bend ish) im sure if it would cost you no more than materials you would do this as well

Re: material for exhaust valves
 

stainless..what type of stainless you have to go figure out yourself...they need to be heat treathed etc etc...hardened and what not. Most honda valves are already stainless steel

Re: material for exhaust valves
 

lol becuase contemplating machining your own valves from mild steel to save a couple bucks is far from ghetto :l


Post pics when your done

Re: material for exhaust valves
 

I know nothing of the sort. For "casual" water injection users, exhaust valve temps are in line with non-WI engines making the same power. For serious WI users running 70%+ water:fuel the exhaust valve temperatures are greatly reduced.

Link me to wherever... whomever... makes these claims and I will smash them into a fragment.

I'm going to go out on a limb here and say all modern valves are stainless. I can say I am right about that 90% of the time, since 1985, but wouldn't be surprised if the real number was 95%.

Valves are not billet, and if you had a set made I would not trust them. Notice any valve made since pre-WW2. The stem is made out of a friction-friendly stainless alloy, the head out of a temperature-friendly alloy, and the head is spun very very very fast, brought into contact with the stem for a split instant so it friction-welds itself on + released from whatever fixture is spinning it.

The steam flowing over the valve is of lesser temperature (heat being a catalyst, and what you worry about in this particular alloy selection) than the steam flowing over the exhaust valve in a non-WI setup of equivalent power. The Infernal Combustion Engine is really just an open cycle reciprocating steam engine aka Harris Cycle engine... two pounds of water is formed for every pound of fuel ingested... what do you think causes all that pressure that pushes the piston down? Hot air like Heywood/Taylor LIE about? If hot air where all that + a bowl of grits, we would spend millions of dollars constructing nuclear reactors to heat air, not water, to turn turbines. But, we don't. The expansion of wet steam is about as good as it gets for practical applications.



PS - the record for a bone stock LS head, strapped to a sleeved/built 84mm LS bottom end, is in the 750 whp range. You are making the n00b error of trying to over build your engine to band-aid your own ignorance. Engines are made of metal, and therefore strong - the soft meat between your ears trying to bend the metal engine to it's will is weak and prone to failure. What are you going to do? Spend more money? Or start thinking *real* hard?

Re: material for exhaust valves
 

I really dont think that there is steam in a water injected engine. Ask yourself how hot a combustion chamber gets and how hot the exhaust valve gets. The valves are going to be constantly dry. Once the water gets past the turbo and starts cooling in the exhaust is when you get actual measureable moisture.

Stock valves are going to be more than plenty. Pistons, rods, and headgasket are going to go way before the valves.

Re: material for exhaust valves
 

Ichigo Kurisagi, please refrain from making tech posts and stick to kicking ass.

If you heat wet steam to the point it dissassociates, the component H and O cannot join together to create water so they seek out Fe and Al to react with. This causes the pits in combustion chambers "that comes from detonation"

Re: material for exhaust valves
 

Go ahead and proof whitey and the rest of us og hmt guys wrong. If you want to cast your own block and make heads from scratch with your own port design and valves then just do it



Your way beyond any of us if you can design and do these parts



Also if you know anything about machine work a company doesnt do a one off part for 100 bucks hands down



For me to get a product i have been wanting to do for sometime and have already been able to get to work for myself will cost $5000 in orders just to do it hence why I havent


This is through rpm designs the guys who build the billet throttle bodies that so many companies sell


He's a small company 2 guys and it takes that so your mystery machine shop that will make valves for you are horrible business people. I would like there # so i can buy their equipment when they go out of business in the next 12 months.


Thanks

Re: material for exhaust valves
 

Hmmmmm. Well, isn't water one of the byproducts of combustion? :l