fyton2v
SILVER Star
My engine runs smooth. Timing is set to 7 degrees BTDC; I'm certain of this. The engine is stock, included the distributor. It's one of those weird 78 era dizzy's that has vacuum advance and I think also retard. It has two vacuum ports. Currently running 87 octane of California gold, which involves 10% ethanol. Running 33s on 4.11 gears. I'm near sea level. I'm pretty sure my vacuum lines are connected correctly, but I wouldn't bet my life on it. At idle, adding a little suction to the advance port does increase RPMs.
I can advance the timing and get a bit more power, but (as usual) at a certain point, I'll get predictable knocking. In this case, however, at 7 degrees BTDC the engine sounds and runs great through all gears, even under load. EXCEPT ... when it's doing 55+ mph while crusing in 4th. At that speed, even on flat ground, just a little throttle can generate what I'm pretty sure is a light knock. It's that telltale ticking/clicking sound. I probably inherited this noise from the PO. I've done so many things to the motor recently that it's a heck of a lot quieter. Now I just hear more problems.
So, what should I try first? I'd like to be able to not retard timing more than the BB. Could it possibly be plug gaps or could the dizzy be out of whack? Odd that it seems to work great at all gears/RPMs until that 55mph point. Meaning, I can take it up a hill in 3rd under heavy load and it be just fine. Same for 4th. I can rev it in 3rd going flat out and it also doesn't seem to have a negative effect.
Thanks in advance for any tips!
I can advance the timing and get a bit more power, but (as usual) at a certain point, I'll get predictable knocking. In this case, however, at 7 degrees BTDC the engine sounds and runs great through all gears, even under load. EXCEPT ... when it's doing 55+ mph while crusing in 4th. At that speed, even on flat ground, just a little throttle can generate what I'm pretty sure is a light knock. It's that telltale ticking/clicking sound. I probably inherited this noise from the PO. I've done so many things to the motor recently that it's a heck of a lot quieter. Now I just hear more problems.
So, what should I try first? I'd like to be able to not retard timing more than the BB. Could it possibly be plug gaps or could the dizzy be out of whack? Odd that it seems to work great at all gears/RPMs until that 55mph point. Meaning, I can take it up a hill in 3rd under heavy load and it be just fine. Same for 4th. I can rev it in 3rd going flat out and it also doesn't seem to have a negative effect.
Thanks in advance for any tips!