At what point would you step up to ferrea hollow stem valves

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Here the 2.25"MP Hemi next to a 2.18" B/RB MP destined for a set of 452's....
 
The difference in weight is only 5.5g 152.2 vs 146.7..........
 
Yeah, but the valves also have gravity on their side. I think some of yall are over thinkin this stuff. There's just no way in hell I'd run a hollow valve. I think it's splittin hairs and it's best to look elsewhere for "upgrades".

Initially the cam moves the valve, but after it starts moving you need spring to control the inertia and control bounce. Lighter valves
Have less inertia, kinda like lighter weight pistons are easier on your rods and bolts.
Bingo Duane


On valves. The valve is held onto spring with the locks and retainers making it part of the assembly as a whole.
The weight of the parts must be controlled to prevent them from doing what you don’t want them to do. You must consider all the parts as 1 part and all of its weight combined as 1 part.

The spring controls the valve & It’s combined weight with the retainer and lock.

In this scenario for an example, let’s say you have to dumb bells. The small on is 5 lbs. pick it up and hold it over your head, arm fully extended, then shake it back and forth. As fast as you can within a total swing area of 1 foot fore and aft.

Now try I again with 50lbs.

Same idea with the valve, retainer and locks.

To answer the OP’s question, I’ll start be saying, “Good question!” I’ll take a stab at it by saying, once you see/discover a short coming.
OK, that was easier to say than discovered.

I’ll take a second stab at it and suggest a lighter valve would be good or just better if your building a very hot street machine or bracket racer that see action every weekend.
This would help in the longevity of the spring and help in a quicker reving engine.

What exactly are you building this engine for?
Is the cost worth it to you?
 
The only reason I have made it through 47 years of racing is I believe in the keeping it simple (KIS) method of engine building. I save money where I can and spend where I have to. I’ve gone 8.40@160 mph with standard stainless steel valves in my big block and 9.42@138 in my small block without “fancy” parts. The last valve spring I broke was back in the 1980’s I broke three inner springs with a 750 lift cam engine that I raced three days a week. We found the issue and it never happened again.
 
Bingo Duane


On valves. The valve is held onto spring with the locks and retainers making it part of the assembly as a whole.
The weight of the parts must be controlled to prevent them from doing what you don’t want them to do. You must consider all the parts as 1 part and all of its weight combined as 1 part.

The spring controls the valve & It’s combined weight with the retainer and lock.

In this scenario for an example, let’s say you have to dumb bells. The small on is 5 lbs. pick it up and hold it over your head, arm fully extended, then shake it back and forth. As fast as you can within a total swing area of 1 foot fore and aft.

Now try I again with 50lbs.

Same idea with the valve, retainer and locks.

To answer the OP’s question, I’ll start be saying, “Good question!” I’ll take a stab at it by saying, once you see/discover a short coming.
OK, that was easier to say than discovered.

I’ll take a second stab at it and suggest a lighter valve would be good or just better if your building a very hot street machine or bracket racer that see action every weekend.
This would help in the longevity of the spring and help in a quicker reving engine.

What exactly are you building this engine for?
Is the cost worth it to you?
The exact build is 10.00 dart. I'm sure you'll want more info but that's just the goal for now, hopefully be able to run it locally every chance next season
 
If you run Ti valves you need copper beryllium seats. Unless you are running 8K and over I would not bother.

Coatings solve that issue. Running CuBr is one thing, finding someone with the PPE to machine is it another.

DLC and CrN would be advisable. Either one makes the valve job hold up exceptionally well with regular stellite seats.

*if* a person was wanting to run uncoated valves a company outside of Milwaukee makes a material called Moldstar90 that is commonly used for valve seats in Ti valve engines.

Have you priced out Ti valves yet? Two Ti intakes is more that one set of Ferrea 6000 SS valves. It seems like you would pick up more with a solid roller cam than spending 3k on valves, lash caps, retainers, locks and a new set of springs. All of the will more than likely have to be changed.

That said the reason for lightening the valve train with is typically to gain RPM, extending the powerband beyond where a steel valve deal would experience valvetrain instability. Like >7500rpm, which I will guess this engine won't see.

My reason for going Ti valves in our 511" low deck is 8800rpm.
 
Coatings solve that issue. Running CuBr is one thing, finding someone with the PPE to machine is it another.

DLC and CrN would be advisable. Either one makes the valve job hold up exceptionally well with regular stellite seats.

*if* a person was wanting to run uncoated valves a company outside of Milwaukee makes a material called Moldstar90 that is commonly used for valve seats in Ti valve engines.

Have you priced out Ti valves yet? Two Ti intakes is more that one set of Ferrea 6000 SS valves. It seems like you would pick up more with a solid roller cam than spending 3k on valves, lash caps, retainers, locks and a new set of springs. All of the will more than likely have to be changed.

That said the reason for lightening the valve train with is typically to gain RPM, extending the powerband beyond where a steel valve deal would experience valvetrain instability. Like >7500rpm, which I will guess this engine won't see.

My reason for going Ti valves in our 511" low deck is 8800rpm.
Great points, I'll be staying ss & when I go to solid roller I'll get some beehives & ti retainers because I'll still only hit 7k
 
Great points, I'll be staying ss & when I go to solid roller I'll get some beehives & ti retainers because I'll still only hit 7k

That is a good plan. I might check out "TensileMax" retainers sold by Manley. It is lighter than tool steel/CM, strong and less expensive than Ti. It is commonly used in endurance type engines.
 
Re: faceplated 4-speed

I have one in my GTS and it is relatively street friendly, stays in gear and shifts excellent at higher engine speeds. I think it about 14-1600 for a 9310 faceplated gear set. To clarify that is 2-3-4. 1st gear is not face plated so you can put it in and out of neutral without shutting off the engine. 235-60-14 bias DOT tire.

Do it!

Screenshot_20210809-070645.jpg


Screenshot_20210809-070540.jpg
 
Coatings solve that issue. Running CuBr is one thing, finding someone with the PPE to machine is it another.

DLC and CrN would be advisable. Either one makes the valve job hold up exceptionally well with regular stellite seats.

*if* a person was wanting to run uncoated valves a company outside of Milwaukee makes a material called Moldstar90 that is commonly used for valve seats in Ti valve engines.

Have you priced out Ti valves yet? Two Ti intakes is more that one set of Ferrea 6000 SS valves. It seems like you would pick up more with a solid roller cam than spending 3k on valves, lash caps, retainers, locks and a new set of springs. All of the will more than likely have to be changed.

That said the reason for lightening the valve train with is typically to gain RPM, extending the powerband beyond where a steel valve deal would experience valvetrain instability. Like >7500rpm, which I will guess this engine won't see.

My reason for going Ti valves in our 511" low deck is 8800rpm.


RPM isn’t nearly as important as overall valve length and head diameter. There is no arbitrary RPM where you switch from stainless to titanium valves. Or even when you switch to smaller stems. There is never a negative going to a lighter valve.
 
The only reason I have made it through 47 years of racing is I believe in the keeping it simple (KIS) method of engine building. I save money where I can and spend where I have to. I’ve gone 8.40@160 mph with standard stainless steel valves in my big block and 9.42@138 in my small block without “fancy” parts. The last valve spring I broke was back in the 1980’s I broke three inner springs with a 750 lift cam engine that I raced three days a week. We found the issue and it never happened again.
And this sums up the basics, unless you're running in a heads-up class where minimum ET wins every time, those hollow stem valves aren't needed for reliability "float"-wise, even tho' they will improve output.
 
In the context of big blocks with 2.20 diameter, 11/32" stem valves at five and a half inch long there is most certainly an RPM guideline for switching to Ti valves. Call Victory, Ferrea, a cam grinder etc. and they will tell you the same. Inertia does not rise in a linear fashion to rpm and the momentum of the valve and required force to control it's motion (ie the spring) increases exponentially. There is a reason why motorcycle engines use Ti valves....because they rev.

Take an engine that makes peak power at 7500. Stab some Ti intake valves in it and watch the powerband carry 2-300 RPM higher.
 
In the context of big blocks with 2.20 diameter, 11/32" stem valves at five and a half inch long there is most certainly an RPM guideline for switching to Ti valves. Call Victory, Ferrea, a cam grinder etc. and they will tell you the same. Inertia does not rise in a linear fashion to rpm and the momentum of the valve and required force to control it's motion (ie the spring) increases exponentially. There is a reason why motorcycle engines use Ti valves....because they rev.

Take an engine that makes peak power at 7500. Stab some Ti intake valves in it and watch the powerband carry 2-300 RPM higher.
Agree and we have not even touched on retainers and spring shape.
I looked into going to a beehive spring for less assembly weight,
But depending on your cam specs, it is difficult to find a beehive spring with adequate spring pressure. Also imho the same reason a hollow stem is weaker, so is a solid stem at a smaller diameter.
Everything like usual becomes a pros and cons. Big diameter valve
More air flow, but heavier, small stem valve more airflow and lighter,
But weaker etc.
 
There are some very light, high PSI spring in the 1.400-1.560 diameters (Assuming a 2.00+ installed height). At one time I thought all high PSI springs were 1.625-1.640" OD. My 511" has 1.600 OD Isky 9998-RAD's and if I re-spring it I'll remove some spring mass there. It already has DLC coated Ti locks and retainers. It will be interesting to see the results.
 
Man,....I can't recall which Member here had a set of prototype beehive triples they were about to run thru the gauntlet, @AndyF , or @IQ52 , or.......pretty sure it wasn't JRob @RAMM.....it was in the B/RB forum.....lost track of that thread....among a bunch of other stuff....lol!
 
I don't see the downside of a well made hollow valvestem.
3/8 hollow pushrods are the norm and they're longer/more slender and no one thinks twice about them. They also see the same forces as the valve does.
It's possible to drill a valve too deep and make the head weak, which is why I say "well made".
Less stress and less chance of spring resonance by lightening the valve seems like a win in all cases to me.
 
Conical springs come in double springs, not sure about triple. Less weight, lighter retainer. Never heard of beehive triples....
 
Conical springs come in double springs, not sure about triple. Less weight, lighter retainer. Never heard of beehive triples....
Me either. I'm sure there's lots of things I've not heard of, but like you no triple beehives. They may be out there though.
 
So You wouldn't run a Hemi under any circumstances, I mean, a long valve with a 2.25" head diameter & a 5/16" stem is total catastrophe...
It depends. I use a mp long 2.08 intake on my w2,s. I have .705 lift at the valve. The stems are 3/8. over 650 pounds of open spring pressure. I do have titanium retainers and 10 deg single locks.
How much would I gain going to a smaller stem versus the reliability. Not to mention the cost. Not worth it to me.
 
RPM isn’t nearly as important as overall valve length and head diameter. There is no arbitrary RPM where you switch from stainless to titanium valves. Or even when you switch to smaller stems. There is never a negative going to a lighter valve.
I don't disagree with this post, but it does seem to me that valve length is partly related to rpm from the perspective that a longer valve allows for a taller installed height for the springs which are required for higher rpm with a given cam lift. You can't get one without the other, whether it is mechanical clearance to the guide for high valve lift, or adequate spring pressure to control the valve train with that lift a a certain rpm. They are all interrelated imho.
 
It depends. I use a mp long 2.08 intake on my w2,s. I have .705 lift at the valve. The stems are 3/8. over 650 pounds of open spring pressure. I do have titanium retainers and 10 deg single locks.
How much would I gain going to a smaller stem versus the reliability. Not to mention the cost. Not worth it to me.
What’s that valve length again?
 
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