Lighter intake valve

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Little Mouse
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Lighter intake valve

Post by Little Mouse »

To lighten the intake valve would it be advantage overall to change the guide and use the smallest stem or just leave things alone and use a hollow stem valve. sbc stainless steel valves.
Alaskaracer
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Re: Lighter intake valve

Post by Alaskaracer »

I'd go to Ti first.....on average they weigh about half what a SS valve does....if budget allows....
There are also different valve profiles that are lighter than others....another possible option...
I'm not a fan of hollow stem valves, but they do have their place...
Thinner stems is also an option, but also depends on overall use....how much of a difference will it make compared to what you have.....
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Re: Lighter intake valve

Post by mag2555 »

Why do ask this question?
Are you having issues , trying to avoid issues or some of both?
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Re: Lighter intake valve

Post by Little Mouse »

I'm thinking not worth all the cost and effort just keep 11/32 with a hollow stem. Not really heard of folks having a problem with hollow stem.
Will be high rpm but driven street miles not sure using a titanium intake valve a good thing. Where I want to spend money is for the latest conical valve springs and a lighter tool steel retainer.
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Re: Lighter intake valve

Post by Alaskaracer »

As far as I know, the Corvette uses Ti valves, and pretty much any crotch rocket does. I know ducati does...Nothing wrong with running Ti on the street if you have the correct valve seats....or coated valves...

But here's the bigger question, what do you consider high rpm?? And how often?? How much street? Every engine will have an rpm range where it's happiest, and everything else is a compromise. An engine set up to be a high(er) rpm engine will likely run like a dog at lower rpms, at least to a point...and what about what's behind it? Street manners don't translate to high rpm race performance at all...so pick your poison....

I'd just concentrate on optimizing what you have instead of trying to reinvent it.....Conical springs are good, but not always the best or correct answer.....might want to talk to the cam company you use and see what they recommend...
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Re: Lighter intake valve

Post by BOOT »

Smaller stem and Hollow prob would be best but I'd choose smaller stem over hollow if the head needed guides anyway.
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Re: Lighter intake valve

Post by mag2555 »

Steel retainers for a conical spring are already lighter Or at least a match for a titanium retainer for a standard valve spring.
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Re: Lighter intake valve

Post by 1980RS »

I put a set of hollow stem intakes and sodium exhaust valves in my large port Vortec heads, I am betting I can get a lot more RPM poetical out of them over the heavier solid stems.
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Re: Lighter intake valve

Post by Little Mouse »

I just want to make sure this engine makes power to 8,000. Will be buying new heads and all that I'm interested in come ready for 11/32 stems. Afr likes to use 8 mm stems can't see why other aftermarket heads don't do the same. Yes the conical springs end up with a lighter retainer no matter what you do the spring itself lighter and I like that the inner spring is supported top and bottom the inner spring does not rub the outer spring. I'm talking about the dual conical spring comp sells.
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Re: Lighter intake valve

Post by rebelyell »

Little Mouse wrote: Sat Dec 25, 2021 9:10 pm I just want to make sure this engine makes power to 8,000. Will be buying new heads and all that I'm interested in come ready for 11/32 stems. Afr likes to use 8 mm stems can't see why other aftermarket heads don't do the same. Yes the conical springs end up with a lighter retainer no matter what you do the spring itself lighter and I like that the inner spring is supported top and bottom the inner spring does not rub the outer spring. I'm talking about the dual conical spring comp sells.
if you're working with production iron heads, you can use thick-wall "guide liners" aka Kline in an 11/32" stem head ... and use 8mm valves ... Howards/Comp Eng had been selling an entire valve & liner kit to do just that. Now, how effective is going from 11/32" to 8mm; dunno ?
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Re: Lighter intake valve

Post by Momus »

The answer is simple to me.

It's to use a Chromium nitride coated titanium valves with 7 or 8 mm stems.


Absolute reliability, half the weight or less, Single spring, spring forces and retainer weight reduced by about 50% and greatly reduced friction and wear on every part of the valve train and rated for any rpm. Bronze guides.
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Re: Lighter intake valve

Post by Little Mouse »

What kind of seat would be needed for that ?
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Re: Lighter intake valve

Post by Momus »

Little Mouse wrote: Sun Dec 26, 2021 10:41 pm What kind of seat would be needed for that ?
You could fuss around and install bronze seats made of one of the various alloys or use what you have in the head.

The CrN coating is very hard and adherent and low friction as well as appearing to be highly resistant to micro welding and with low seat pressures seems to stand up to hard valve seats well, not that the nickel aluminium bronzes are particularly soft anyway.

Experts may have different opinions, but on the cool side I would run them and gain the experience.
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