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Old 18th February 2012, 07:08   #1006
Sandy309
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Join Date: Jan 2010
Location: Cornwall
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Quote:
Originally Posted by xsi16v View Post
what spec/size valves are going in? or is that top secret?
I won't be saying the valve sizes I'll be using, but single piece stainless. The exact sizes I use aren't available as a direct fit, so I have to re-machine valves designed for other applications. I use various sizes according to spec, it's a fallacy that bigger valves equal more power, there are so many side effects at work that valves sizes need to be developed alongside the cam profiles, CR and chamber/porting/seat work to get the delivery you want. I don't use "big valves" as most people would; moderation is the key. Anything over the standard seat insert sizes means oversizing the inserts, and I don't like changing valve seat inserts unless I have to, it adds alot of cost and risk to the process. So most of my development has been based on valves that fit on the standard inserts safely.
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