valve question

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Nov 18, 2005 | 10:12 AM

f-4x4

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valve question

are thry good valves and are they pretty much like stock just stainless

http://cgi.ebay.com/ebaymotors/Ford-...QQcmdZViewItem

item number if link dont work 8013768214

Nov 18, 2005 | 05:59 PM

cwheel

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From: Blacksburg, VA

I bought these exact same valves from mad dog via ebay. I'm fairly sure they work (they're at the machinist right now getting a 3 angle valve job). The one thing that surprised me is that the ones I got are multi-groove (as opposed to what the picture shows, which are single groove). My old valves were single groove (79 351m), but the machinist said that he has multi groove keepers that will work, and that multi groove are just as good. Elsewhere, I've heard the opposite. So I don't know what to believe.

Hmm, helpful post huh?

Nov 18, 2005 | 07:03 PM

f-4x4

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actualy the post was helpful. and at least i know at least iknow one person has them

Nov 18, 2005 | 07:34 PM

Bill_Beyer

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From: PacNW

Multi groove valves are designed to rotate to distribute the heat and IIRC to make up for the lack of lead in gasoline. They are definitely not performance pieces because in order to allow the valves to rotate the keepers have to remain a little loose. At higher RPMs the keepers tend to be too loose and let go of the valve stem entirely. That's known as a V.B.T. (Very Bad Thing) and results in ex$pen$ive noi$e$ before the engine stops running.

Last edited by Bill_Beyer; Nov 18, 2005 at 07:36 PM.

Nov 18, 2005 | 09:20 PM

cwheel

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From: Blacksburg, VA

I hadn't heard of that before...at what RPM are we talking about here? My rebuild isn't designed to go above 4500k. Should I be worried?

Nov 19, 2005 | 12:09 AM

Bill_Beyer

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From: PacNW

I've never seen a specific RPM limit written anywhere. I know that Ford Motorsports says that for any engine built for "extended high RPM usage" multi keeper valves should be replaced with single keeper style valves.