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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