Hi Bob,
I went with a new chilled cast iron billet cam rather than a regrind. My
understanding was that the chilled cast iron billet was harder and
deeper. My old lifters were still very good, according to the LBC
mechanics doing the engine (VanDeCarrs) -- only a few pits on a couple
of them, so I had them reground and hardness checked at Integral Cams.
Engine is not together yet -- thoughts?
Don Malling
Robert M. Lang wrote:
> Hi,
>
> Been there, done that.
>
> Twice.
>
> But I also have to stress the importance of initial cam break-in. Like I
> keep saying this week, the first 20 min. of a cam's life will determine
> whether it'll last or not.
>
> As an aside, it is possible to "see" internal engine damage by looking
> closely at the oil or even going to the extreme of cutting open the oil
> filter (if you have a spin-on adapter) and looking for metal particles.
>
> One solution to the "soft lifter problem" is to go to a completely
> different source for lifters. Dave didn't mention this, but BFE can sell
> you some lifters from some sort of Ford application (this mod requires
> drilling out the lifter bores in the block) to a fatter lifter. Note:
this
> solution is not cheap - but it will last. And this is particularly
true if
> you go to radical cam profiles and a lot of valve spring seat pressure.
>
> Also, several of the UK suppliers sell hardened lifter sets that will
meet
> the min. lifter hardness specs.
>
> But you have to decide - do you want to spend $150 on the good lifters or
> $75 for the ones that might be good.
>
> And as a parting thought, recall that much of a TR6 cam's lubrication is
> from "splash" off the crank. Some modern oils don't cling like the older
> oils did, so it is quite possible to get metal to metal contact inside
> your motor, especially during startup. Related to this is the fact that
> TR6 owners seem to be neurotic about making thier cars idle at
> rediculously low RPM's (less than 800, for example). IMHO, if you you do
> this, you might as well just dump some "black magic" blasting media in
> your sump and be done with it. The "splash" at low RPMs is not very much
> lube to the cam.
>
> I think the ideal solution for the TR6 cam/lifter failure is to
> re-engineer the oiling to the cam (as in make a "spray bar" like some of
> the Datsun racers did in the '70's. If you get better oiling on the cam,
> it'll def. last longer. The "problem" with the cam/lifter thing is that
> while a lot of people are familiar with it (mostly through first hand
> experience), nobody wants to spearhead a campaign to stamp out the crappy
> parts in the stream (because _all of us_ buy on price-points).
>
> I know one TR6 who did two or three cam installs before he broke down and
> did all the "right things", install cam bearings, bore the block for the
> Ford lifters, install the Ford lifters and new cam and then run the motor
> in right. Skip any step and it's likely that your new cam will last 5000
> miles.
>
> Last point - if you think I'm full of it, call any cam grinder and
ask for
> a cam. If they don't have new blanks, they'll want a grindable core. One
> grinder that I worked with last year had "a pile" of ruined cams that
were
> not regrindable. I've resorted to picking up any "core" engines I can
find
> just for the cam cores. I have 5 or 6 engines in the garage (aside from
> the two running engines in the cars and the new one on the engine stand).
> Really!
>
> 'nuff said (for now).
> rml
>
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