Kas,
If idle at start up is the best way to go, why do some cam regrinders /
manufacturers insist that the engine never be allowed to run below 2000
rpm for the first five minutes or so. Seems that Isky lists that method
for its cams. It always bothered me to fire up a new engine and bring it
up to 2 grand since there are so many other things to be worrying about
at that moment and idle would be more comfortable. The one thing that is
consistent in both methods is maintaining the speed constant.
On a completely unrelated topic. Have you tested various designs of
exhaust headers on the six cylinder engines? If so, what works better, 6
equal length into 1, or 3 into 2 into 1, or some other design?
Thanks,
Bill 70 GT-6+
On Sat, 26 Jan 2002 13:28:49 -0800 "Kas Kastner" <kaskas@earthlink.net>
writes:
> Yes, this can happen with ANY camshaft. Generally the surface of a
> reground-cam is smooth but pretty soft and about the only protection
> they
> get is to be parkerized ( a coating). The main problem for
> immediate wear
> is revving the engine, or blipping the throttle when the part is
> new. It is
> hard not to listen to the sound when you've just finished a
> modification but
> unless you give the engine a run in time period of at least a few
> minutes at
> low revs, just over idle you've got a more than fair chance of
> screwing up
> the camshaft. The slow running ( without blipping) allows the
> camshaft and
> other parts to surface harden. I learned this lesson a long time ago
> but it
> still applies. On occasion it will happen even after this
> precaution but
> not often. The other culpert is a camshaft lift curve that is too
> big
> (radical) for the lifter diameter. This is a thing that can happen
> with
> the little lifters of the Spitfire engine. The lobe catches the edge
> of the
> lifter and peels it like an apple.
> ----- Original Message -----
> From: "Russell" <rjmunns@btinternet.com>
> To: "Friend Of Triumph" <FOT@autox.team.net>
> Sent: Saturday, January 26, 2002 9:53 AM
> Subject: Camshaft failure? :(
>
>
> > Damn Damn and Double Damn
> >
> > I have just got back from running my new fully modified spit 1300
> engine
> > for the first time (after extensive rebuild)only to be frustrated
> by what
> I
> > think is a camshaft failure. I booked onto a track day to run the
> engine
> in
> > and all was going well (apart from a couple of small oil leaks)
> until the
> > engine started making a lot of noise. It was not a bearing problem
> but
> > something was definitely amiss.
> >
> > Into the pits and everything sounded ok and all the fluid levels
> and
> > pressures were fine. So back out and no difference, still very
> noisy, so
> > slowly back to the pits. The noise seamed to be induction rather
> than
> > engine noise so we decided to check the valve clearances, all of
> which
> were
> > like barn doors (huge). I assumed the pushrods and followers etc
> had
> > probably just bedded in so started readjusting the clearances,
> only to
> find
> > that number 5 exhaust was only opening a fraction compared with
> the rest
> of
> > the valves.
> >
> > What has gone wrong?
> >
> > My theory is that when the cam was re-profiled the cam lobes were
> not
> > hardened properly and they have all worn away quite rapidly as the
> car had
> > only covered 20 miles before the noise started to appear. If this
> is the
> > case which I suspect it is will it have done any damage to the
> rest of the
> > engine. I already expect swarf to have collected in the sump and
> filter
> but
> > I suspect I will need a full stripdown to clear the engine of any
> metal
> > particles.
> >
> > Very annoying but I would appreciate some views on this! Is it
> common on
> > full race camshafts or am I just damn unlucky
> >
> > Russ (annoyed) :(
> >
> > -----Original Message-----
> > From: Joe Curry [SMTP:spitlist@gte.net]
> > Sent: 26 January 2002 16:03
> > To: David & Krystal Wingett
> > Cc: Friend Of Triumph
> > Subject: Re: Hurry
> >
> > When I was looking into doing a Supercharger on a Spit 1300 I
> found that
> > there were several alternative companies that still make rods (and
> pistons)
> > for these older engines a lot cheaper than Carillo.
> Unfortunately, when I
> > decided to transplant the Honda S2000 engine, I deleted all the
> files I
> had
> > been saving. :(
> >
> > Joe (C)
> >
> > David & Krystal Wingett wrote:
> > >
> > > I think I saw an imitation sold in England (maybe
> Cambridge).
> > Has
> > > any one ells found an alternate source?
> > > DW
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