Thanks for the suggestion. I checked both mechanical and vacuum advance. I
didn't check at various RPMs, but did check total advance. Both were at the
lower end of the range specified in the Bently manual. I also substituted the
distributor off my Mk 2 Spit (which runs good), with the same results.
Larry Quirk wrote:
> Have you checked the mechanical advance in the distributor to make sure it
> is free and providing the correct amount of advance at the specified rpm. A
> good ignition shop will still have a distributor advance machine to measure
> the advance curve.
> Spitman
>
> -----Original Message-----
> From: cecil wise <cwise@southwind.net>
> To: spitfires@autox.team.net <spitfires@autox.team.net>
> Date: Thursday, January 21, 1999 10:08 PM
> Subject: Re: I am really starting to hate this timing thing
>
> >Hi all,
> >
> >I've been having this exact same problem with my '80 Spit. 1st I tried
> lining
> >up the dimples in the gears, then I tried setting the intake and exhaust
> valves
> >at TDC. Next, I tried setting max valve opening at 108 degrees (I have a
> Kent
> >road/rally cam), then tried setting it using their timing figures. All had
> the
> >same result, max power (I use this term loosely) seems to be around 25-30
> >degrees advance at idle, and 35-40 degrees at 3500 rpm (vacuum plugged).
> Even
> >with the timing this advanced, it doesn't ping. I have rebuilt this engine
> a
> >couple of times previously with good results and have had the cam for about
> 10
> >years now without problem. As a desperation measure, I have put the
> original
> >cam back in, but haven't had a chance to get it all back together yet, so
> we'll
> >see if that fixed it, though I doubt it. I just don't know how to solve
> this
> >one.
> >
> >Any help greatly appreciated
> >
> >Cecil
> >'65, '80 Spitfires
> >'62 Vitesse
> >
> >James Carpenter wrote:
> >
> >> You do know that the engine will run better at idle the more advanced the
> >> ignition is, although 30 is abit excessive. Me putting the timing from
> 10
> >> to 20 deg BTDC putt's the idle right up from 600 to 1000 ish. But then
> it
> >> pinks as soon as you drive anywhere, and has no go. The Spifire cam is
> >> symmetrical I think so that 7 and 8 rockers should be "on the rock" at
> 0deg.
> >>
> >> You really need to look at the detailed instructions and pictures that
> are
> >> in the Spitfire 1500 workshop manual to set up the valve timing. It's
> not
> >> an easy job. But getting the correct tooth is less difficult. The marks
> >> left on the cogs by the oil give you good clues. Use the valve cover to
> >> give you 0 deg. That is near enough to allow you to pick the correct
> cog.
> >>
> >> You are tensioning the chain on the right bottom side?
> >
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