Michel,
Michael,
I will supply some pedestals if you will bore them and let me know the stud
diameter -- suggest we find a stock ARP stud/washer/bolts to use if
possible. This would be tested in a high compression, high lift long
duration cam, PI TR6 race car.
Scott -- what ARP stud number? Stock diameter?
chuck
On Mon, May 19, 2008 at 7:38 PM, Scott Janzen <S.Janzen@comcast.net> wrote:
> Goodparts makes a beffy replacement TR6/Gt6 pedestal with its roller rocker
> setup. Not a plug - never used it, but I have had my stock pedestals egg
> out a bit under the nuts /washers. I now have some high quality studs and
> hardened washers and nuts from ARP.
> ----- Original Message -----
> From: "Michael Porter" <mdporter@dfn.com>
> To: "marty sukey" <trmarty@hotmail.com>
> Cc: <fot@autox.team.net>
> Sent: Monday, May 19, 2008 10:25 PM
> Subject: Re: [Fot] Pedistal studs
>
>
> > marty sukey wrote:
> >> Ken,Jack, all. Is this a problem specific the the TR4 engine or is this
> >> something the TR6 and Spitfire folks should keep in mind?
> >>
> >>
> >
> > The TR6/GT6 engines have the rocker shaft supports at the ends of the
> > shaft, so that's a plus. Nevertheless, the pedestal studs are a bit
> > wimpy. One of the things I've been thinking about is the tendency of
> > the pedestals to walk back and forth with increasing valve spring
> > pressure. As one adds stiffness into the valve train--stronger and
> > stiffer pushrods, stronger rockers, etc., there's usually little done to
> > the pedestal studs, and that means the weakest part of the valve train
> > is the one to flex.
> >
> >
> > In looking at the pedestals, it's apparent that they are mostly hollow,
> > with a collar cast into the tops, which fits somewhat loosely around the
> > stud. That means the pedestal, under load, can sort of squirm underneath
> > the nut and washer, which might be one of the reasons for the nuts
> > loosening up.
> >
> >
> > What I'm thinking about doing is boring that collar out to a slightly
> > larger size, enlarging the stud threaded bores in the head, then
> > installing a larger stud that fits snugly inside the pedestal hole.
> > That also allows larger nuts, and considerably more applied tension to
> > hold the pedestals in place. I think that milling the feet of the
> > pedestals perfectly flat and 90 deg. to the stud holes will help a bit,
> > since they seem to come from the factory without precise finishing and
> > over time may deform a bit and allow the pedestal to rock back and forth
> > under load.
> >
> >
> > Cheers.
> >
> > --
> >
> >
> > Michael Porter
> > Roswell, NM
> >
> >
> > Never let anyone drive you crazy when you know it's within walking
> > distance....
> > _______________________________________________
> > http://www.team.net/donate.html
> >
> > Fot mailing list
> > Fot@autox.team.net
> > http://autox.team.net/mailman/listinfo/fot
> >
> > You are subscribed as s.janzen@comcast.net
> _______________________________________________
> http://www.team.net/donate.html
>
> Fot mailing list
> Fot@autox.team.net
> http://autox.team.net/mailman/listinfo/fot
>
> You are subscribed as triosan@gmail.com
>
--
Chuck Arnold
_______________________________________________
http://www.team.net/donate.html
Fot mailing list
Fot@autox.team.net
http://autox.team.net/mailman/listinfo/fot
|