hey guys, have a question maybe one of yall can answer for me. 54 chevy 210 with the 235 and a powerglide. (all original) when I try to rev the engine, I get a lot of stumble/popping. i can see my distributor move with the vacuum advance, so it's doing something, but it should be a more vacuum, more advance thing, right? mine seems to be jumping around/not super consistent. (itll turn, then turn back without letting off the accelerator)
What is your base ignition set to? Pull the vacuum off the advance, it will make the engine rev a little sluggish/slower, but see if that changes anything. How is your fuel pressure? Is the fuel pump pumping enough fuel? Vacuum advance works under the demand of the engine, higher vacuum more vac advance, less vacumm less vac advance. By the time the vac advance starts to back off the centrifugal weights inside the distributor will mechanically advance the timing, should be a smooth transition. Verify the weights and springs work smoothly.
X 2 what RMONTY is stating. Pull the plugs have a look . Check under the cap . Rotor - points gap. Go over the wires - check and listen for arcing . Maybe all this stuff looks like it was new when your neighbor got the first colour TV you ever saw? Which means you should get new stuff - it’s all pretty cheap and easy to change. Could possibly be a vacuum leak or carburetor trouble but I was taught to blame the carburetor last.
I'm sure my timing is off, but I cant find my timing light ATM. I know I'm close, but its still not quite right. I did find my vacuum gauge, seems to hunt between 15-20, but drops with the stumbles which makes sense. the plugs, wire, cap, rotor, ect, are about 6 years old, but have very little run time, the plugs were a sooty black mess, so all that sounds like retarded timing to me. I rebuilt this carburetor last week, but it's not a great unit and has seen it's better days. I debated replacing it, and I may still. the fuel pump is new. I cleaned the plugs, and sanded down the points and regapped them today, but I will replace them if checking the timing doesnt do much.
You don't need a timing light to set base timing. Rotate the engine so the crank is on the base timing mark, not TDC, but actual base timing mark. Mark the distributor body in relation to the distributor towers. Mark towers #1 tower centerlines to the distributor, this way if the cam/distributor are off 180° you won't have to get to actual #1 TDC timing. Remove distributor cap. Loosen distributor clamp. Rotate distributor so that the rotor will be pointing at #1(or #6 if 180° out) tower when the cap is reinstalled. Tighten distributor clamp. Reinstall cap. Fire her up and see how she sounds. This will get you within 1° of the base timing if your mark was good. I do this all the time when starting a dormant engine or new/rebuild. Why mess about stabbing/rotating the distributor when all you need is in front of you
on the 235, the bb on the flywheel is the base timing mark, correct? when I pulled my dizzy to prime the oil pump, I lined that up with the marker on the bell housing and pointed the rotor at #1.
I'll admit I forget what the exact labels on the crank mean, I recall a ball or bb, then a few other marks as well as an alpha-numerical mark. Car isn't near me so I'll go dig up the service manual and see what it says. [EDIT]: Set Octane selector to "0". Loosen distributor and rotate til pointer and ball line up. Tighten down. 53/54 engines are 2° ATDC (IIRC back then gas was in the low 80's Octane) Points is .019"(new) .015"(used) Plug Gap .035" Compression should be 130Psi Remember that the crank spins 720° for every 360° of the cam/distributor. You will need to verify that your distributor is in time with the cam. [/EDIT]
When you get it running right don’t expect it to be any better than 0-60 in 20 seconds. They are not known as a performance car. Good luck
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