SBC stock valve spring installed height??

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pdq67
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SBC stock valve spring installed height??

Post by pdq67 »

What is it for my old -462, (1.94"/1.50" dia.), medium valve stock heads??

1.70", 1.75", or 1.80"???

I am having trouble finding this out is why I ask.. If it is in HP's old book, "How to Hotrod SBC's", I missed it....

Thanks,

pdq67
Kbails
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Re: SBC stock valve spring installed height??

Post by Kbails »

my 1967 462 heads with stock gm 194 valves are at 1.7-1.72 with no shims
Long Island, NY
pdq67
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Re: SBC stock valve spring installed height??

Post by pdq67 »

Kbails wrote: Sun Feb 18, 2018 10:31 am my 1967 462 heads with stock gm 194 valves are at 1.7-1.72 with no shims
Thanks Kbails,

I'm finding 1.70", 1.75", 1.78", and 1.80", so go figure?

I figured 1.70 plus a skosh so I am fine.

pdq67
Dan Timberlake
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Re: SBC stock valve spring installed height??

Post by Dan Timberlake »

72 truck and passenger car shop manual pdf to download for free.
http://67-72chevytrucks.com/vboard/show ... ?p=5781194
1972 chey engine specsm .JPG
Not sure if those are the right heads, but a solid lifter lifter 350 //might// be similar.
1.719 =/- .031
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pdq67
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Re: SBC stock valve spring installed height??

Post by pdq67 »

Elgin Performance Valve Springs PN RV-1943X for SB Chevy - Stock Diameter - 125 lb. @ 1.750", 325 lb. @ 1.200"

It say's 125 pounds @ 1.75" installed height.

I guess what I am asking is, will I be OK at 1.70" installed height or should I get a set of .050" taller keepers?

pdq67
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Re: SBC stock valve spring installed height??

Post by user-17438 »

As long as you have enough retainer to guide / seal clearance and no coil bind, you are good.
Dan Timberlake
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Re: SBC stock valve spring installed height??

Post by Dan Timberlake »

Hi pdq67,

125# seat pressure. That does NOT sound like a "SBC stock valve spring".

Maybe along the lines of 3927142 for use with the early off-road cam for real Trans Am use?

The free length is important to, specially if the pressure ( force, really ) open and closed is not confirmed.
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Re: SBC stock valve spring installed height??

Post by pdq67 »

I call the old -142 valve spring, the Z-28 spring even though it was used with the old -140 solid cam.

Thanks Dan, I will check free height when I install them then check everything else.

pdq67

PS., they are supposedly good to .600" lift...
Brian W
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Re: SBC stock valve spring installed height??

Post by Brian W »

Iirc. The 943x are the z-28 spring.
1943x are .100 longer. Used several sets of those a million years ago on dirt track sft deals. Work good but would always break the dampener, but were cheap so just remove and replace.
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midnightbluS10
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Re: SBC stock valve spring installed height??

Post by midnightbluS10 »

Dan Timberlake wrote: Sun Feb 18, 2018 11:37 am 72 truck and passenger car shop manual pdf to download for free.
http://67-72chevytrucks.com/vboard/show ... ?p=5781194

1972 chey engine specsm .JPG
Not sure if those are the right heads, but a solid lifter lifter 350 //might// be similar.
1.719 =/- .031
Also try here. They have all kinds of stuff. Original shop manuals. Brochures. All kinds of literature on all kinds of vehicles and parts.

http://oldcarmanualproject.com http://www.oldcarbrochures.com and http://www.oldirononline.com
JC -

bigjoe1 wrote:By the way, I had a long talk with Harold(Brookshire) last year at the PRI show. We met at the airport and he told me everything he knew about everything.It was a nice visit. JOE SHERMAN RACING
pdq67
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Re: SBC stock valve spring installed height??

Post by pdq67 »

Thanks midnight,

I am going to use them with .500" solid flat-tappet lifter cam.

I'm shooting for about 125 to 130 or so seat and 325 or so over the nose. If I have to, I will use my .050" taller keepers? I know these springs aren't all that fancy , but I figure that they should go to 8,000 rpm. For how many times, I don't know?

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Re: SBC stock valve spring installed height??

Post by falcongeorge »

I always pull springs with flat dampeners apart and de-burr the dampeners before I run them,they can be a bit raggedy-ass straight out of the package. Tedious? Well yes...so is changing valve springs with broken dampeners... :wink: :D
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