In the early 80's, I had prepared my TR 4A engine pretty much as a race engine,
though I was just using it to lead-foot on the streets... and street race every
American Muscle car I could entice at a signal... (Hey, I was a teenager...and
I'd always win, unless we managed to get to 4th gear, where the cars with a
higher top speed could finally pull away!) I went through three cams... one
real quickly... the others maybe a year, etc..... I like to think that I
gave them a slow running as Kas suggests.... but I can't remember exactly...
I'm guessing I definitely gave it a good run-in, when new piston rings were
involved, but I might not have been so kind when it was just the cam... Their
failure could be in part, to the lack of run-in hardening that Kas mentions...
in addition to that, I always suspected my valve springs. I was using "Bishop
and Buehl" a machine shop in southern Cal... and they were all about V8's and
Formula 1 cars... my little British 4-banger was just a fun diversion for
them... and they put massive springs on my engine...
In the early 80's, one could not buy a new camshaft, so I had to use re-grinds
from Norris Cams... after the failures, Darrel Buehl always pointed to the
cam... and just said I needed to find a new cam, rather than a regrind. I
searched the nation, but there was no internet back then, and my efforts locally
and by phone failed.
I believe I should have just removed those massive Chevy valve springs and put
in something a tad more tame.
...and needless to say... in the future... I'll heed Kas's advice stated here
today!
--Justin Wagner
Kas Kastner wrote:
> 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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