Where is the 9 Degees timing on this picture

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Big Kat

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I have a 1970 Pontiac Catalina with a 455 motor. Where on this picture is the stock 9 degree mark? If you notice on the picture there is a 4 a 0 a 4 an 8 and then a 12. On top it says before/Aft



 
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On the side that says BEFORE it is between the mark that says 8 and the next mark going to the left in the picture, which is unmarked, but is 10.
 
melsg5 said:
On the side that says BEFORE it is between the mark that says 8 and the next mark going to the left in the picture, which is unmarked, but is 10.
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What are the other numbers? Also when I checked it was past the 12 about an inch past it to the left. which I'm guessing would be about 16 degrees its now on the 12 2 degrees past stock I ran the car and it ran beautiful. Except for the carburetor which I'm having problems after it got rebuilt. I'm going to send it back. I want to change it to electronic choke instead of a divorce choke. How hard would it be to change the car to take an electronic choke carburetor?
 
The numbers indicate the number of degrees before TDC, BEFORE, the #1 cylinder fires on the compression stroke. Not clear why you want to switch to a electric choke but you would need a different carburetor.
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melsg5 said:
The numbers indicate the number of degrees before TDC, BEFORE, the #1 cylinder fires on the compression stroke. Not clear why you want to switch to a electric choke but you would need a different carburetor.
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Well I'm having allot of trouble with this quadra jet. I'm sending it back. The divorce choke has a little rod on it for some reason it won't let the choke open up all the way it's a pain. I figured an electronic one would be better. I'm thinking of getting a Barry grant but wanted to know how to change the car to an electronic choke
 
Mel is right, each timing mark is 2 degrees in value from the one next to it with 4, 8 and 12 noted. So yes, the last mark is 16 though it is not noted.

What problems are you having with the carb? Is it just the choke that is not working properly? That may be as simple as a few adjustments. Check this article for that, good info which may help you;

http://www.hemmings.com/mus/stories/2009/10/01/hmn_tips2.html
 
You know, if memory serves, you have to have both the choke and your timing dialed in correctly with those old engines or you're not going to be happy.

Get your timing dialed in first. You put in the electronic distributor right? How is the timing advance handled by that distributor? Is it mechanical?

This is what I would look to do;
• Get the initial timing set correctly.
• Adjust your idle mixture.
• Check on the timing advance of the new distributor, adjust as required.
• Adjust the divorced choke.

Once you get those basics dialed in, then you can evaluate the performance of the carb with the engine.

Keep us posted on your progress!
 
Kevlar said:
You know, if memory serves, you have to have both the choke and your timing dialed in correctly with those old engines or you're not going to be happy.

Get your timing dialed in first. You put in the electronic distributor right? How is the timing advance handled by that distributor? Is it mechanical?

This is what I would look to do;
• Get the initial timing set correctly.
• Adjust your idle mixture.
• Check on the timing advance of the new distributor, adjust as required.
• Adjust the divorced choke.

Once you get those basics dialed in, then you can evaluate the performance of the carb with the eng

Keep us posted on your progress![/QUO


Ok I got the timing to 9 degrees. Whas happining is that the car hesitates when I punch it. Also the choke does not open all the way. Have no I dea why? Try to see how to adjust it but had no luck. I will take a picture and show you. The little butterflies to the choke do not open all the way. There's a little rod that connects to the choke and it will only let it open very minimal. If i take the rod out the car reves really high. It's driving me bananas! This is why I want to change carburetor all together to a electronic choke.
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with the engine off and completely cold disconnet the rod from the choke linkage. The rod should be bent so that the head of the rod is one rod diameter above the hole in the choke mechanism with the choke completely closed. This puts a slight preload on the choke blades when completely closed and cold. The carburetor also has a choke pulloff which has to be adjusted. THis is a small vacuum canister on the passenger side of the carburetor front. With the engine off and the choke fully closed push in the rod which will slightly crack open the choke blade. A good starting point for the opening is .025. You should have the factory Chasis Service manual and refer to the fuel section for the carburetor set up specs. If the choke is not fully open the secondaries on the carburetor may be locked out. No matter what type of choke you have you will have to know how to do the basic set up procedures.
 
OK here is some pictures of the Carb. I missed the litte black rod that connects to the choke.



 
So yesturday I spent most of the evening working on the car. I finally figured out why my rebuild carburator was having issues. When I installed the new MSD ignition distributor the wire that goes to the coil and the igniton was not putting out 12 volts I checked this by going to the store and buying a volt meter. I ran a relay beteween the igniton wire and the coil and that solved my issue. Apperently an MSD ignition must have 12 volts going through the ignition wire mine only had 10.2. Wow what a big diffrence, that thing fires up like a dream, I dont even have to push the gas pedal down. Now I can really adjust the carburator as I am now getting a great spark. Those MSD electronic distributors are awsome. I should have read the instructions a litte better about the 12 volt ignition requeired to the coil. I belive since the spark was really weak that the carburator was being flooded and cuasing the issue. I will take good pictures and post them up later today. Thank God I am done! The wife wants me to paint the cabinets in the kitchen white this weekend. I for one vote on taking the car out to Santa Cruz for a spin.:D:D
 
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Glad to hear you got it solved. The Quadrajet you have is an excellant choice for that car once it is correctly adjusted. You have the benefit of decent gas mileage on the small primaries and lots of power when those large secondaries open up.
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Alright!
First off, it's Ok. Guys aren't supposed to read the instructions .....
Second, I second the motion for the Santa Cruz cruise! (though I suspect that yours, mine and every member's vote on the matter is trumped by the wife's .... )

... oh well ... enjoy those nice white cabinets! :)
 
If it's a heat choke I bet it's not opening all of the way cause It probably has plates blocking the exhaust crossover in the intake manifold. If it's blocked heat won't go through it and your choke stove won't open all of the way.
 
kendallpeterson1963 said:
If it's a heat choke I bet it's not opening all of the way cause It probably has plates blocking the exhaust crossover in the intake manifold. If it's blocked heat won't go through it and your choke stove won't open all of the way.
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Ok How can I fix this? I can get the choke to open all the way.
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Kevlar said:
Alright!
First off, it's Ok. Guys aren't supposed to read the instructions .....
Second, I second the motion for the Santa Cruz cruise! (though I suspect that yours, mine and every member's vote on the matter is trumped by the wife's .... )

... oh well ... enjoy those nice white cabinets! :)
Click to expand...

Well Nedless to say Cabintes are shinny white. I dont agree with the wife as I never win anywyas so I just say "Yes Dear". It has saved me lots of headaches.
 
did you correctly adjust the choke linkage rod by bending it so that when cold and the choke completely closed the end of the rod is one diameter above the hole? did you check the choke pull off when the choke is fully closed and the diaphragm on the pulloff is fully retracted?
 
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