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    Originally posted by down_the_plug_hole View Post

    FYI, This is a bespoke stellited exhaust valve based on my design from a decade ago which has been thoroughly tested and works.
    They can actually stand up to lots of abuse.

    I need to make 100 min, or ideally 250.
    Hi Gareth, welcome back! I'll be interested in a set of valves but like most, I need some idea of price before I committ.

    Will they fit the standard guides? And use the standard collets?

    Richard
    Mabel is a white 1972 Mk1, TV8, ZF 4HP-22 auto,
    2016 RBRR finisher. 400 mile C2C 21/22 April 2018!

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      Originally posted by mole42 View Post

      Hi Gareth, welcome back! I'll be interested in a set of valves but like most, I need some idea of price before I committ.

      Will they fit the standard guides? And use the standard collets?

      Richard
      Hi Gareth,

      Interested, but as Richard says above.

      Pete

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        Unlike "normal" modified s/s valves (21-4N) these have been hardened on the stems to prevent galling and excess wear - the bane of cheap versions.
        This means they can be run in normal cast iron guides, and don't have the extreme loose clearances which I have seen in many aftermarket items...
        (no comment!).
        It is recommended to use Colisbro if you like, and fit a stem seal, but it's not essential.
        They remain compatible with the STD collets and caps, and are a little lighter.
        I am thinking of making a few, marginally longer to make up for use of the Jag cam follower which is a lot deeper, but considerably lighter.
        This should then use a much lighter valve spring (will need to find one which suits this role).

        I would suggest any performance difference would be felt to give the engine the top end power and output it SHOULD have had from the factory but didn't.

        Because these are stellited and nitrided, the price is pretty much double,- but stripping down a V8 for defective valves and/or excess oil consumption is not cheap at all.
        (Been there done that,- don't want to go there!).
        It's better to pay a bit more and get it right first time, as I found out on a 24v engine to my cost, once the stem seals failed.....

        As for the economics of the thing.
        This is not the place for a discussion., only preliminary stuff. (ie. PM)
        SORRY.
        Last edited by down_the_plug_hole; 9th February 2018, 16:35.

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          Tell me this thread is going to continue please ! most interesting of the lot !!

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            Yep, thanks for the efforts too.
            There are 2 secrets to staying on top :- 1. Don't give everything away.
            2.

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              SOC mag arrived today, good summary of all your hard work Neil, although one of the pics is upside down and others are mislabelled
              Chris

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