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Discussion Starter · #1 ·
Ok so I got this 73 nova back in December. The guy I got it from couldn't tell me much about the engine because from what I gather he got it the way it is or just didn't remember the details. The car has a 350/350 setup with a Hypertech Street/Strip ignition system, 3" pipes, long tube headers and it has a cam, which I believe to be a mild street cam although I really don't have anything to compare it too since this is my first cammed SBC. I installed a Edelbrock 1406 carb on it and it runs well and the only issue is it's a bit hard to start after it's been running anywhere from 10 to 40 mins. It has a weak turn over like a weak battery. It will turn over slow and then normal, it's very random. I have checked all the connections, cleaned them and dielectric greased them. Since I've gotten the car I've got it running much better than it was but the performance is still a little weaker than I would expect. I believe my wife's V6 Ford Escape to give it a run for it's money :rolleyes:

After researching the issue I came to the conclusion that the timing may need some adjusting and possibly be the cause of my slow start. The seller also hinted, "that the timing needed some adjustment and "I needed to find someone familiar with old cars to do it because it was finicky". So now I've been reading up on setting the timing since I've never had to worry about advanced timing ect and only every messed with the normal initial factory specked timing.

I've been reading pages of info on setting the timing. Setting the initial timing I know you disconnect and plug the vacuum advance and shoot for between 14 - 18* and see if I get any backfires or throttle resp delays. Now after that I'm a little confused. As far as the mechanical advance goes do I get the engine up to a certain rpm (say 3000?) and check my timing at that point and would that be my total timing? Can I use a regular basic old school timing light for this? This is the point where I'm a little confused. Would appreciate any help and advice.
 

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You've pretty much got it figured right. Assuming your TDC is accurate, you'll want to install a timing tape, make sure you get one for the diameter of your balancer. You'll then want to check to see the rpm where you're "all in" with your mechanical advance. Set your total at that rpm and see where your initial is at idle with the vacuum advance disconnected. That'll give you a baseline to adjust from.
 

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Discussion Starter · #3 ·
You'll then want to check to see the rpm where you're "all in" with your mechanical advance. Set your total at that rpm and see where your initial is at idle with the vacuum advance disconnected. That'll give you a baseline to adjust from.
First off all I appreciate the response. Could please elaborate a little, I'm not sure what you mean by "all in" and "setting total at that rpm". Could you explain how to do that. Sorry for needing this broken down but after initial timing it gets a little confusing since I've never had experience with worrying about that. :confused:
 

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With the vacuum advance plugged, and the timing light hooked up, accelerate the car by hand checking the timing until it does not go any higher
That is your"all in" timing. Your initial timing plus mechanical advance. You will need to know what RPM is at that point. A friend watching your tach can help you there.

All in should be about 30-36 degrees. If it is coming in too late, say 4000 rpm or so, you may need to change your mechanical advance springs to bring the timing in earlier.

I would also replace the cap and rotor, and plugs. Maybe get a new set of plug wires.

You will have to fiddle with the idle speed and the idle screws when you are setting the timing as well. All part of the equation. When you have set the timing, screw the idle screws in one at a time until it starts to stumble and then back it out until it is running smooth.

Should idle at about 600 to 700 in gear. Remember NOT to snap the throttle when you have the car in gear!!

I probably have missed something but others will correct me.

Have fun, practice, and you will sort it out.

ray
 

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I would install a heat shield over the starter solenoid if it doesn't already have one. My car used to crank over slow when warmed up and driven for a while due to the headers being so close to the solenoid. Put the little heat shield on there and the problem was gone.

You've got some good advice already here for setting the timing. I'd shoot for 10-14 initial and 32-36 total timing and bring it all in around 3000 RPM or so. Your vacuum advance should be plugged to the manifold source which on an Edelbrock carb is the driver's side port. If you get around 10-15 degrees from your vacuum advance that should be good.

Generally the bigger the cam duration, the more initial timing you'll want to run. With a stockish type cam you can get away with 8-10 degrees initial. Bigger cams will like 16-18 initial and really radical cams will want more than that or to the point of just locking out the timing.

Let us know how it goes!
 

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I had a slow start on my car too. Went to the Ford Solenoid and helped, put in a new starter, that helped but was still slow.

Went to a 140 amp alternator and upgraded the battery and charge wires and grounded everything, it works way better. I have an MSD box, electric fans and a stereo and that was just too much for the old alternator. Also the funky wiring by the headlights did not help. The old alternator was just not keeping up with the electrical load.

Chase one thing at a time rather than shotgunning everything. Small changes and then test. Try the free stuff first and then keep going. Everyone has got stories of stuff they bought and is now sitting on a shelf unused and unneeded. I know I do. :D

ray
 

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OR

Drive it, and I mean DRIVE it.

Find an empty road. Stop on side of road. Nail the gas...if you hear pinging, then turn the distributor just a hair in one direction. (you will need to loosen the clamp a little)
Drive it again, if you still hear pinging move it a little more. If it got worse, then move it the other direction.
Drive it again, and listen for the pinging. Once you remove the pinging by adjusting the timing, lock it down. From here it's very minor adjustments, but usually pretty darned good and is just where your engine likes it.

Only tool needed is a wrench to loosen the distributor clamp.

Not the most efficient way of doing things, but is another way of doing this task.
Enjoy that car!
 

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Discussion Starter · #12 · (Edited)
Ok, I got a chance to mess with the timing today. When I check TDC and have the piston at TDC and pull the distributor cap, the rotor is pointing to the passenger side of the center of the engine, so if 12 o'clock is center of the back of the engine and 6 o'clock is the center of the front of the engine that would make #1 plug at 5 but the rotor is actually pointing at 7 o'clock. I hope that's not confusing. I didn't actually adjust the timing bc I don't have a tach yet but when I put a timing light on it at idle it's showing 36 on the timing tape I added to the balancer. I didn't pull the vacuum from the distributer though but that still seems pretty high. The car does run and start fine before all this and I didn't actually do any adjustments with the distributer since I had no tach.

What am I missing now?

Forgot to add that the #1 plug wire does go to what would be the closest post to the #1 cylinder on the distributer.
 

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Discussion Starter · #14 · (Edited)
Yes I sure it was. At one point I totally rotated the engine by hand and checked it and the rotor was pointing the opposite way and I rotated it again and it was then pointing back to the front of the engine.

Could it be the wrong balancer possibly? I had TDC on the piston and the balancer mark at 0* on the timing tab.

When I got the car the previous owner said it was really hard to time the car and I may need someone familiar with old cars to adjust it. Makes me think something part of the timing system is not correct. Also running at idle with the vacuum advance plugged it still it was showing 36* which I thought was really strange.
 

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Is your #1 Spark plug wire at the 7 o'clock position on the dist cap? If so it sounds like the previous owner may have dropped the distributor in one tooth off and moved the wires to compensate.

I would try re-stabbing the distributor so that the rotor points at 5 o'clock and re do the wires.
 

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Discussion Starter · #17 · (Edited)
you might want to use a high torque mini starter
It does have a mini high torque starter on it but as someone suggested I need to add a heat shield which it doesn't have. I will be adding pretty soon.

Is your #1 Spark plug wire at the 7 o'clock position on the dist cap? If so it sounds like the previous owner may have dropped the distributor in one tooth off and moved the wires to compensate.

I would try re-stabbing the distributor so that the rotor points at 5 o'clock and re do the wires.
The #1 plug wire is at the 5 o'clock position on the distributer so that's correct but when at 0* on the timing tab the distributer shows a hair past 6 o'clock. I'm wondering if they dropped the dist. in with the timing already advanced bc like I said it does run good as is as far as no knocking or backfires ect. before adjusting it. Yesterday I checked the timing with the vac advance plugged and I was getting 21* and with vacuum I was getting 31, if my memory serves me correctly. I advanced the initial a bit and took it for a test drive and got some knocking so put it back a few degrees using the trial and error method with a lose dist hold down bolt as suggested by someone in this thread. I rotated it back some and fixed the knocking but really didn't get any performance increase either way. I really need to get a tach or something to read the RPM's to set it correctly. I have a tach/dwel device from way back when (old school) but it doesn't work on my distributer which I'm assuming is because it's a HEI setup.
 

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Ok so I got this 73 nova back in December. The guy I got it from couldn't tell me much about the engine because from what I gather he got it the way it is or just didn't remember the details. The car has a 350/350 setup with a Hypertech Street/Strip ignition system, 3" pipes, long tube headers and it has a cam, which I believe to be a mild street cam although I really don't have anything to compare it too since this is my first cammed SBC. I installed a Edelbrock 1406 carb on it and it runs well and the only issue is it's a bit hard to start after it's been running anywhere from 10 to 40 mins. It has a weak turn over like a weak battery. It will turn over slow and then normal, it's very random. I have checked all the connections, cleaned them and dielectric greased them. Since I've gotten the car I've got it running much better than it was but the performance is still a little weaker than I would expect. I believe my wife's V6 Ford Escape to give it a run for it's money :rolleyes:

After researching the issue I came to the conclusion that the timing may need some adjusting and possibly be the cause of my slow start. The seller also hinted, "that the timing needed some adjustment and "I needed to find someone familiar with old cars to do it because it was finicky". So now I've been reading up on setting the timing since I've never had to worry about advanced timing ect and only every messed with the normal initial factory specked timing.

I've been reading pages of info on setting the timing. Setting the initial timing I know you disconnect and plug the vacuum advance and shoot for between 14 - 18* and see if I get any backfires or throttle resp delays. Now after that I'm a little confused. As far as the mechanical advance goes do I get the engine up to a certain rpm (say 3000?) and check my timing at that point and would that be my total timing? Can I use a regular basic old school timing light for this? This is the point where I'm a little confused. Would appreciate any help and advice.
Make sure the mechanical advance located under the distributor plate moves freely!
 
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