any tips on how to check timing are appreciated too, never done that. I'll also try reading up.
but what about the plenum thing? Does one half of the carb fuel one side of the engine?
i'll post the method i use to set timing, however, it it is on several threads on the forum . for optimum performance disregard the factory settings as they were designed to help the car pass emissions laws and different setting often yields better perf, mileage and engine cooling.
if you set your timing for optimum perf, you need an adjustable vacuum can p/n bwd v311 or smp vc31 then set it so it adds only 6 degrees of advance.
check your timing with the vacuum disconnected and connected at the same throttle position and post the results.
the point of peak cylinder pressure is round 14 degrees after tdc but this info is not useful to you.
yes you may need to "recurve" your distributor which is often as simple as replacing only one of the advance sprigs with one from mr gasket p/n 925D available at summit racing for around $7.00 . i will tell you which spring to replace if it looks like you need one.
your plugs look xlnt and show that you are not burning oil.
the low compression on the one cylinder may be caused by a leaking valve.
yes, there is no dwell to set per se with the pertronix. . it comes with a gauge to set the clearance.
grab the distributor shaft and wiggle it side to side to see if it has much play . if it does, make sure there is clearance for the pertronix with the shaft pulled closest to it.
make sure your carb is fully opening when the gas pedal is on the floor.
you may need to adjust the vacuum secondary setting on the carb to get the optimum perf out of the engine.
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