Started to build the heads after receiving new cam kit but the valve keepers don't fit the valve stems. Will have to contact Flatlanders Racing on monday to check part #'s. Damm and the temp's here are going up to the 70's next week, and now I don't have the parts to work.
(11-06-2010 06:49 PM)not2old Wrote: Started to build the heads after receiving new cam kit but the valve keepers don't fit the valve stems. Will have to contact Flatlanders Racing on monday to check part #'s. Damm and the temp's here are going up to the 70's next week, and now I don't have the parts to work.
Those look like original valves, I would recomend replacing with single groove one piece stainless aftermarket valves.
Its a common for the heads to fall off those valves, ruining many engines.
I used some from a place on ebay called Alex's parts and they worked great reved that motor to 6500 rpm hundreds of times and they were only $108 a set. You Might have to email him I didnt see any listed now.
There are lots of other brands as well. Be carefull to match the keepers to the retainers, they come in 10 degree and 7 degree in case you try to find multi groove keepers to re use your valves.
If I remember correctly the Multi groove ford keepers will only work with ford retainers. These are designed to fit on the valve semi loosely to allow the valve to rotate while in use. The better single groove will clamp on to the valve solidly and not allow rotation.
As is stated above many 351C catastrophic engine failures were caused by valve failure. The multi-groove keepers were actually designed to touch each other on both faces when installed The thought was it would allow the valve to rotate. Why it was thought to be beneficial is unknown to me, perhaps even wear on seats and guides. Because the keepers actually touch on both faces the valve is not held tightly allowing it to move side to side slightly which hammers the grooves on the valve stem and keepers causing failure of one or both (this is worsened by excessive guide wear and high RPM). The end result is the engine swallows the valve and grenades (literally) the engine. The real fix is to, as suggested, replace the valves with single groove valves and keepers. If that is not possible use hardened after market multi-groove keepers that positive lock on to the valve and do not allow it to rotate. The valve springs supplied in your kit have a specified installed spring height dimension, make sure it is correct. If it is not there are several ways to correct (valve spring shims, spring cups, offset keepers, retainers). Also beware of replacement rocker arm fulcrums. In the past I experienced multiple failures of after market fulcrums. Valve train geometry is very important for optimal performance and longevity. If the heads are milled, the block is decked, the seats are high or deep, or more likely a combination of the above, you may need a non-stock push rod length. As with cam timing, multiple small errors add up and cause less than desired performance problems that are hard to diagnose after assembly.