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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