Biggest exhaust valve in a stock head
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How big is the intake valve you are using...? That will determine the maximum exhaust valve size.
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First of all, a 2.19" valve diameter ISN'T stock but, with that intake valve size a 1.810" exhaust valve can be used in all applications; a slightly larger one can be installed into some engines with low valve overlap.
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2.083" is the OEM production intake valve diameter. I have used a 1.840" exhaust valve in that application to be able to accomplish a better "short side radius" when bowl porting.
It gets to be a battle of which is better suited for that application because that 1.840" valve also gets closer to the chamber wall.
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You can get any "custom" made valve you want if you don't mind paying for them. Seems to be a giant waste in a lowly D3VE head.
I haven't seen that size or length valve made from Inconel in any catalogue...
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I've used 2.250" with 1.76" Pro Flows quite sucessfully with radiusing the combustion chamber edge around both valves (trace out the head gasket hole) to help unshroud them. The correct cam for your application goes a long way to making your engine breath real deep too, probably money better spent that thousands of $'s on valves.......
Rob
Rob
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Competition Products has a reduced stem 1.8 for the earlier heads. If a BBC valve is the length you need then you could simply install guides to match the stem diameter.
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The LENGTH of the valves and their tip distance are different for D3VE heads than a D0VE or earlier head. They are NOT interchangeable.
S.I. has Pontiac valves which fit that combination well. A 2.11" intake valve #6004SG-45° and a 1.770" exhaust valve #6007SG.
Both are the correct length for the D3VE heads and have a shorter tip length of .250" to get a taller valve spring installed height.
Of course they're your heads and you know what you want so, it's all up to you.
Right now I'm looking at maybe going with the Omni valves. Has anybody on here used them? I might need to get the measurements of you Randy since I don't have the stock ones out of the head yet to measure so that I get the right ones.
So I can find them here:
SI Pontiac Competition Series Stainless Steel Valves
pontiac competition series swirl polished stainless steel valves
www.rpmrons.com
What are the installed heights with these valves in a D3 head?
Did you install valve seats? These are the industry standard as used by GM on the LS engines:
Powder Metal Valve Seats - Dura-Bond Bearing Company
Valve Seat Technology Has Changed Modern engines put much higher levels of thermal and mechanical stress on valve seat inserts. To handle the more severe conditions within this… Read More ›
www.dura-bondbearing.com
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