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this week I have fitted my new 600 holley carb and also the Edelbrock inlet manifold on my car,
Reading the Holley supplied info it said that it had been test run and settings were good enough to get the engine running, and they were right!
I have fitted a new standard mechanical fuel pump
which works a treat as one of my connections to the carb wasn't quite tight enough, wow what a spray of fuel! thats now OK. So question is how do I check the ignition Timing, I see no marks on the front pulley and little from the rear/gearbox end, usually there are marks showing degrees on a pulley to set at ? degree before TDC, my engine now runs but I would like to get it set up pretty much right myself.
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get a strong flashlight, the timing marks are on the harmonic balancer, wipe it off, its right behind the crank pulley, bump the motor they will come up from top dead center on #1 to 60 degrees or so advance.It depends on the balancer, Also depending on how your distributor is set up....
you should be @ 16 degrees initial ( idle ) and 34 degrees total advance ( 3500 rpm ). This is only a guide line your engine could require more or less timing.
hope this helps Smiler
Thanks Chris, I couldn't see the timing marks because the Harmonic balancer was covered in surface corrosion. Now I have found the markings I feel a bit like Howard Carter in Egypt, wonderful things!

Mikael I did buy your book, but haven't had the chance to read it properly yet but I think it might be too advanced for an ordinary street pilot, I don't have a track round here to do testing, although it must be grand if you can find one. The vacuum gauge is a must though I got that one! but again, good help from people Thanks again.
Peter, be very careful in drawing conclusions from your timing marks until it's verified that the two-piece harmonic balancer has not shifted with age. The outer ring was pressed together with a rubber strip in between it and the hub, and age tends to shrink rubber. This allows the press-fit to slacken and the outer ring to shift backward. moving the timing marks towards 'retard'. I've seen visually undamaged but over-age balancers in which the sacred timing mark was 160 degrees off! I've also seen 43-year-old balancers in which the mark was perfectly aligned.

If it turns out yours is still correct, many of us make a chisel or a scribe mark (or even paint) across both halves of the balancer and check those index marks periodically to verify the parts haven't moved.
quote:
Originally posted by Bosswrench:
Peter, be very careful in drawing conclusions from your timing marks until it's verified that the two-piece harmonic balancer has not shifted with age. The outer ring was pressed together with a rubber strip in between it and the hub, and age tends to shrink rubber. This allows the press-fit to slacken and the outer ring to shift backward. moving the timing marks towards
'retard'. I've seen visually undamaged but over-age balancers in which the sacred timing mark was 160 degrees off! I've also seen 43-year-old balancers in which the mark was perfectly aligned.

If it turns out yours is still correct, many of us make a chisel or a scribe mark (or even paint) across both halves of the balancer and check those index marks periodically to verify the parts haven't moved.


Bugger, just when you think your on the right bus!! I can only think that the way to get TDC is to do the plug job, where you can break up a plug and extend the end section, turn the engine until the piston makes contact with the plug, mark the pulley. Then turn the engine the opposite way and again mark the pulley, TDC MUST be midway between the marks, or is there a better method? but thanks for again invaluable info.
that is the most accurate correct method with the heads on / in the car

for a 'just to see if it's close' method you can use a drinking straw in the plug hole touching the piston & turn the crank through by hand while watching

if the balancer has spun it's probably more than the few degrees that you wouldn't be able to tell by the straw method

paint stripe across the rubber is a good idea

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