Thanks for the clarification. The car did come with a chassis and body manual, both look untouched. Correct distributor according to manual is 1112109. I looked up the specs which are slightly different for 1973 with medium advance at 11-15 at 1800 and max advance being slightly higher at 14-18 at 2900. So I may be able to end up with slightly less initial advance. Max Advance Degrees at inch of vacuum is the same. I don't want to do any major mods to this very original car, but just want it to run as efficiently as possible.
My MSD put in 22* of advance +14* initial. Why would I need vacuum advance? have run the motor both with and without v advance cannot feel any differance.BTW I have owned and built this car In 2001. I have put total of 8756miles in 16 years.That comes to 547.25 miles per year, hope I don't wear the motor out. Kenny
Vacuum advance is for improvements in gas mileage on extended highway runs. Don't care about gas mileage? Then you don't need it. With the small amount you drive your car, it doesn't matter.
Have had the distributor reworked on the '73 Century's 350 4bbl stocker. Set up at 6 degrees initial advance with 34 degrees all in at 2600 rpm, using 91 octane ethanol free fuel. Also new Delco ignition wires, plugs, rotor, cap, points and condenser. Stage 1 shift kit with governor adjusted to shift at 4200 rpm at WOT. This is a stock motor with maximum power rated at 3800 rpm, so no need for a higher shift point, at least for the moment. Has really woken the car up, and the peg leg rear lets right rear wheel put down a big, smoky black strip of rubber off the line, even with 2:73's. Next mod is 21/2 inch duals with dynomax mufflers and a taller air filter in the stock housing. Hoping for better mileage if I can keep my foot out of the secondaries
I can't for the Life of me Dial in the Timing! Anyone in San Jose CA that has this down real well? I will pay in beer haha The cam is a TA 212 idk if makes a difference but I replaced the Vac canister on the MSD ready to run dizzy, with an adjustable one and verified I have the 18* bushing in the distributor to and when I stabbed the distributor in and set to TDC to get it going it will idle very low and not hold in Drive. I Advance it to the #8 line on the tab and it smoothes out a bit.With the timing light on and vac advance plugged I bring up the RPMs and make the *30 mark line up with the #0 and it feels okay but surges in Drive I attempted to limit the vac advance to 10* but yea no luck I'm really pulling my hair on this one, then engine isn't stock so I'm having a hard time dialing it in or even driving normally For a good while it would idle perfect In drive, but would ping @ part throttle so I got the new canister and now I can't even get it to idle or drive so it can ping , Sent from my SM-N920P using Tapatalk
Leave the vacuum advance out of the equation for now. Do not even hook it up until you have the engine running right on the mechanical advance. With the MSD distributor, the 18* bushing will give you 18* of mechanical advance. That means you will need 14* initial to run 32* total. The problem is that if you have light springs installed, some of the mechanical advance can be in at idle speeds making it difficult to set the initial advance accurately. What you can do is use the heaviest springs you can find and get the idle down as low as possible, then set the initial timing. It sounds as if you may have other problems. If the carburetor is lean, or the idle system isn't set up correctly, you will have trouble getting it to idle correctly with a cam. If the cam is too small and the static compression is too high, it will ping on pump gas, and lean mixtures will make that even more likely.
I put the heavy springs back in and it made a difference it idles in drive now, noticed a nice stumble One time I attempted a quicker take off, still a ping @ light throttle I will attempt to set it down to 14* initial timing and go from there Sent from my SM-N920P using Tapatalk
Swapped the heavy springs into it, and Set the Initial Timing to 14* . I did this by using the timing light and matching up the 30* mark on the balancer to the #2 on the timing tab. Should put my Initial Timing of 14* + 18* of mechanical on the MSD = 32* of total timing without the VAC Advance hooked up. Idles a okay a little rough in Park and totally wants to Die in Drive. Could I possibly need to now focus on the Carb? It's a 850 DP with all 4 screws turned only 1 full turn out, used to run fine minis the ping , so I don't think it's too lean maybe I need 16* initial timing for a total of 34* without the vac advance unless there's something weird going on with this engine -_- Sent from my SM-N920P using Tapatalk
The engine isn't a high compression one yet the last owned had a TA 212 Cam put in it during the rebuild. Without the Vac Advance hooked up, I was able to get the car to turn in and idle nicely both in Park and Drive but it takes past 14* initial timing closer to 18-20* gobs of torque cause it moves easier but even without the vac advance now it pings. If I back the timing back down to the 15* initial Plus the 18* built into the distributor , it will want to stall @ idle after a while and throttle response is bad unless im a speed , even then there's a slight ping Sent from my SM-N920P using Tapatalk
There is something else wrong. Doesn't sound like it has anything to do with the timing. The torque converter may be too tight for the cam. That would significantly increase the load on the engine, especially at low speed, in a heavy car, and it would also explain it wanting to stall at idle. What is the rear gear?
Totally right, I overlooked this, The last owner did mention he kept the Th350 but has been built yet I am unsure if what stall converter is in it but from the looking @ it under the car, it appears to be stock, I'm running 3.42 gears as well not too sure if that also adds to it Sent from my SM-N920P using Tapatalk
The 3.42's would be better than taller highway gears. Taller gears would put more strain on the engine.
So I had to pick up the Skylark from my Girlfriend's apartment , was feeling adventurous and not giving up and realizeed how cold it is......So I get there Give it a pump of gas and didn't even mess with the timing but it's at around 17*initial and even had vac advance in it and it fired up and idled smoothly in park and drive, jumped in it and drove home, at a steady 65 mph still slight ping but not as bad but completely a different car........ I think the key factor is that it is really cool out and the car isnt running as Hot, I didn't notice while attempting to tune it prior , it was getting and feeling hotter than I ever remember it being , no blown head gasket oil is clean, possibly I need to swap the thermostat and Radiator antifreeze , The question for you Larry is will an overheating engine have such erratic Timing Issues? I actually replaced the spark plugs today and gapped them to 45 since it has the MSD Distributor and Blaster 2 They plugs I replaced were black like carbon, not wet just black evenly , when I'd check then before they used to be a nice brown color Hmmm maybe I've been overheating especially since the gauge has been working on and off Sent from my SM-N920P using Tapatalk
It should not be pinging if you have your timing set correctly. It obviously isn't running lean if your plugs are black. Not having good gauges on your car is not a good idea. If it is running hot, you could be getting some vapor lock. That would explain why it ran better when it was cool out. I think you have several issues going on at the same time. I'd look carefully at your float levels. Also check the power valves in the carburetor. Sounds as if you are running rich. Find out how hot it is running. Hope you at least have an oil pressure gauge.
I have replaced timing chain and installing the distributor as a new installation (and replaced the carb also). I hold my thumb on #1 cyl until compression pushed it away. Set balancer TDC to 12* on timing cover. And rotated the distributor so rotor pointed to #1 terminal. Tried to start. It didnt sound like it fired on all cylinders. could not make it idle for more than ~2 seconds. I changed it down to ~ 5* but it didnt help. Service book say 2 degrees but I thought it could handle more after reading some posts here. I noticed a major fuel leak on my pipe, but I just want to double check if this is the right way to set initial ignition?
When you cover the #1 spark plug hole with your finger, it is important to just BUMP the starter over, a LITTLE at a time. When you feel compression, stop. The mark should be under the water pump. Finish turning the crank CLOCKWISE with a socket and breaker bar. Then install the distributor so the rotor points at #1.
!0-12* is fine. It sounds to me like you may have over shot the mark, then turned the crank to the exhaust stroke. Try it again.
