[DeTomaso] More valvetrain for 6143

[Tomas Gunnarsson]

As shown in the pictures I sent you, this is not the case. The taper is the same for the aftermarket pieces but the OD is definitely not the same. There are keepers that are made slightly oversize to move the retainer down on the stem and undersize to move the retainer up on the stem. My error is in excess of .080" which is beyond normal adjustment from keeper size. I was under the impression that the solution was to use Boss retainers with aftermarket keepers but if there are Boss keepers that fit the stock retainers I'd rather get that I guess. If these are stock Boss retainers they look nothing like mine anyway: http://www.mustangmonthly.com/techarticles/mump_1001_boss_351_block_buildup/photo_10.html

Tomas
  ----- Original Message ----- 
  From: jderyke at aol.com 
  To: guson at home.se ; detomaso at realbig.com 
  Sent: Thursday, January 21, 2010 10:33 PM
  Subject: Re: [DeTomaso] More valvetrain for 6143


  In a message dated 1/21/10 12:40:46 PM, guson at home.se writes:


    Are there single grove keepers that have the same diameter as the stock multigroove keepers? I couldn't find any myself. The suggestions so far have been using Boss retainers that supposedly have a smaller hole than the stock retainers and would fit the commonly available keepers.


  All keepers for Ford 11/32" valve stems are about the same dia. The way multi-groove ones work is, the halves butt together slightly before clamping the valve stem. This lets the valve shift slightly and prolongs the life of a valve job. But because the stem is always a little loose, multi-groove keepers have unlocked at high rpms.... Single groove keepers don't butt together- if you look closely, there's a space between the two halves of a single groove pair, very tightly clamping the stem in place. 
  Boss keepers are single groove 7 degree, made from forgings rather than weaker stampings. 'Boss' keepers drop right into stock 7 degree steel retainer washers. 10 degree racing keepers won't fit stock 7 degree retainer washers, and there are special single-groove keepers (both 7 & 10 degree) of different heights for changing valvetrain geometry in certain cases without machining. FWIW- J DeRyke