Valve stem diameter

Valve stem diameter

Joined: September 9th, 2010, 6:02 am

March 22nd, 2012, 1:31 am #1

Hello all,

I have another question about my 408 build. I now have 4V CC heads, and was about to buy valves for them, when I was asked the question, "Do you want the 11/32 stem or 3/8 stem?" I don't know which I should go with.. I had one manufacturer tell me I should use 11/32 because they are lighter, but then I wondered shy the 3/8 were made.. Must be for strength... I guess the 11/32 is the stock diameter. Anyone have any advice, or should I just stop worrying and get the one piece stainless, single groove 11/32 valves? I have a feeling I'm over thinking this, but after so much research already done for this engine, I might as well not stop now

Thanks!

~Mike
Quote
Like
Share

Joined: April 30th, 2005, 7:32 am

March 22nd, 2012, 2:24 am #2

If your valve guides are in good shape stay with the stock 11/32 valves
ebay has a seller, "alex's engine parts" I think, that sells a set for about
$100.00 get the stock length not the .100 longer
Quote
Like
Share

Joined: September 9th, 2010, 6:02 am

March 22nd, 2012, 2:37 am #3

Thats actually the seller I was already looking at A guy that has 3 351s recommended his valves to me. But I'm going to have to replace the guides as one is cracked, and I might as well do them all if I'm going to muck with them anyhow. But alex's parts dont seem to carry the 3/8 valves... If I'm changing the guides anyway, should I go with 3/8, or are the cheaper/more available 11/32 good enough? Is it worth bumping up to the 3/8 or am I just adding weight to the valve train?

Thanks for the response Carl
Quote
Like
Share

Joined: April 30th, 2005, 7:32 am

March 22nd, 2012, 3:03 am #4

I went with 11/32. There is an advantage with lightening up the valvetrain.
but for my stuff the gain doesn't justify the expense.The sum of my valve train wouldn't benefit from just changing to smaller valve stem valves.
Your program might be different
Quote
Like
Share

Joined: April 30th, 2005, 7:32 am

March 22nd, 2012, 3:15 am #5



just got these out of the shop tonite
Quote
Like
Share

Joined: September 9th, 2010, 6:02 am

March 22nd, 2012, 5:23 am #6

Nice! I wish mine were that far along. Getting there though
Quote
Like
Share

Joined: May 20th, 2005, 4:48 pm

March 22nd, 2012, 12:46 pm #7

Hello all,

I have another question about my 408 build. I now have 4V CC heads, and was about to buy valves for them, when I was asked the question, "Do you want the 11/32 stem or 3/8 stem?" I don't know which I should go with.. I had one manufacturer tell me I should use 11/32 because they are lighter, but then I wondered shy the 3/8 were made.. Must be for strength... I guess the 11/32 is the stock diameter. Anyone have any advice, or should I just stop worrying and get the one piece stainless, single groove 11/32 valves? I have a feeling I'm over thinking this, but after so much research already done for this engine, I might as well not stop now

Thanks!

~Mike
It's not worth it to add extra weight to the valvetrain...especially on a hydraulic cam or a solid cam that you're spinning up high.

I would watch about the cheaper valves that you find on Ebay. They're cheap for a reason...



Brent Lykins
B2 Motorsports, LLC






Quote
Like
Share

Joined: February 19th, 2005, 5:39 pm

March 22nd, 2012, 1:28 pm #8

Food for thought, NASCAR uses 7 and 6mm valves (.275" and .236" Diam.)!

Mike
Quote
Like
Share

Joined: November 26th, 2003, 2:49 am

March 22nd, 2012, 1:50 pm #9

Hello all,

I have another question about my 408 build. I now have 4V CC heads, and was about to buy valves for them, when I was asked the question, "Do you want the 11/32 stem or 3/8 stem?" I don't know which I should go with.. I had one manufacturer tell me I should use 11/32 because they are lighter, but then I wondered shy the 3/8 were made.. Must be for strength... I guess the 11/32 is the stock diameter. Anyone have any advice, or should I just stop worrying and get the one piece stainless, single groove 11/32 valves? I have a feeling I'm over thinking this, but after so much research already done for this engine, I might as well not stop now

Thanks!

~Mike
epn vavves are undercut and quite a bit lighter than the stock or even some other brands of stainless..

 

http://www.enginepartsnetwork.com/valves.html
Quote
Like
Share

Joined: February 13th, 2006, 4:59 am

March 22nd, 2012, 2:29 pm #10

Brent I sent those exhaust valves but I did have a set that was ground. However the margin left was about .030? The book says stocker is around .080. I did find some non ground ones that were at .075 and sent those. What do you like on stock valve? As some stainless have a shallow margin to begin with ?
Quote
Like
Share