nickpohlaandp

So I picked up a new project and I'm doing a bunch of research and searching around to look for information. One thing I'm having trouble with is finding overall valve heights. What I have is a 6.0 from a 2001 2500HD that's going into a 2001 Sonoma. I just picked it up yesterday so I haven't had a chance to tear anything down yet. I'm trying to figure out what the overall height of the intake and exhaust valve is on the 317 heads. Can anyone help me out here.

Somewhat related, do all of the LS Gen 3 heads use the same length valves, just different diameters?

I tried using the search feature but haven't been successful thus far.

Thank you in advance for any info you could share, links you could post, etc.

00pooterSS

iTrader: (40)

I don't know the length off the top of my head, google search will likely turn that up quickly. The only valve length difference I know of is with 243 LS6 heads, only the LS6 243's though, they are approx .025" longer. I'll try to find more info in a minute

00pooterSS

iTrader: (40)

Found this

Stock LS1 valve length 4.867"


"The LS6 used lightweight valves with hollow stems starting in '02. The hollow intakes saved some weight, but the hollow exhausts were filled with sodium so they ran cooler. Both of these valves are 0.6 mm longer than the others because the cam for the '02 LS6 had a smaller base circle."

0.6mm = 0.0236"

By calculation only 02LS6 valve length = 4.890"

Also stumbled on this, nice little info chart to save to my computer.

http://www.smokemup.com/tech/ls1.php

G Atsma

Cool chart! Though I think they switched the LQ9 duration specs. GM never ran a larger intake-duration cam on any LS engine.

00pooterSS

iTrader: (40)

Manley replacements are 4.874" interestingly, just general info I noticed while looking around. I've never looked up LS valve length, it's fairly hard to find. Info about the LS6 valve being longer is everywhere.

00pooterSS

iTrader: (40)

I noticed that too. After I posted it... doh

nickpohlaandp

That's what I'm finding too. Valve head diameter is easy to find. The valve length is trickier. I've Googled the crap out of it and haven't come up with anything definitive.

Now to look at that chart you posted.

nickpohlaandp

Where'd you find that. I'm curious if the intake and exhaust are the same length. One would assume being a parallel valve head they would be, however, when you assume something, that's when it usually bites you in the ***. As far as the Manley valves being 4.874", I don't think 0.007" is going to make a huge difference on an engine with a hydraulic lifter.

00pooterSS

iTrader: (40)

random google searching, it's all I could find and I looked a decent amount. If I took more time I could likely find it somewhere, but it's not necessarily easy to find.


look up manley valves and see if the intakes are the same as the exhaust

no it wont matter having the additional .007

nickpohlaandp

Yup, that's what I was doing. I've got a 4.8, a 5.3, and this 6.0. When I get them apart I will measure all the valves and see what I can see. Should be interesting.

00pooterSS

iTrader: (40)

Looks like you'll be the one putting the info out there then.

If you could find a website that tends to have a good spec list you could look up an OE valve. Maybe scoggins dickey or rock auto has the info.

00pooterSS

iTrader: (40)

On all cylinders is a great resource, but no valve length mentioned.

On all cylinders may be better than the website I linked before

https://www.onallcylinders.com/2017/...ads-cam-specs/


I found a listing for a stock exhaust valve and it says 4.915 length. But I'm still looking.

00pooterSS

iTrader: (40)

GM intake valve 12563063
GM exh valve 12562954

That's the part numbers I got from a GM parts website, and couldn't find any info using the part numbers.

This is all I have found.. This site shows the lengths, you can try scrolling around more on their website. The links may get taken down since they are a non sponsor website. The intake and exh show to be different lengths

https://www.lsxceleration.com/stock-...-intake-valve/
https://www.lsxceleration.com/stock-...exhaust-valve/

nickpohlaandp

00pooterSS

iTrader: (40)

Retarded how hard that was to find. I'm interested to see if you get the same numbers when you pull yours out and measure. I could only find those measurements on that site so who knows if they measured them or if they found the lengths and copied them to the site...?

In other words, I hate it when I can't confirm info, I only found one good source and one post with one dude stating the length, I'd rather be able to find multiple sources with the same info.

nickpohlaandp

00pooterSS

iTrader: (40)

Agreed and I hear ya. Let us know

omc8

iTrader: (7)

I don't like Manley , but most aftermarket valves are going to be around 4.9 intake and slightly longer on exhaust. REV valves for example are usually a bit longer than most...... on the intake range from 4.89 to 4.915 and the exhaust is 4.93 these are shelf valves not custom.