Just turn the distributor clockwise and start it up.
You won't hurt it.
I would guess you still have the hold down clap just snug at this point.
You won't hurt it.
I would guess you still have the hold down clap just snug at this point.
Cam gear and timing chain
- Thread starter Carmine
- Start date
Carmine. You said you turned the idle down. I would put it back where it was then set #1 back to top dead center and look at the rotor to #1 plug wire. If you need to pull the distributor to get yourself some adjustability and it won’t fall back in the pump you can turn the pump with a screw driver to get things lined back up. Been a while since I did a Pontiac but I believe you can turn pump to line it up.
Thanks everyone for all the responses. I won't get back to this issue until Friday. I'll do what is suggested in these threads. So that I understand, to advance the entire distributor one tooth, I should bring #1 up to TDC, remove the cap, see where the rotor is pointing, if at #1, pull the distributor turning it clockwise one tooth, lining up the oil pump shaft and dropping it back in??? Lets say at TDC, the rotor is pointing to #6 tower in the cap. Can't I follow the same procedure regardless if it's #1 or #6, but it should be one or the other?? I'm only looking to advance it one tooth. Or do I have this back asswards as usual?? Is there another, better way?? Many thank, Carmine.
Sitting here having a cup of coffee, I just can't let this idea escape me. Prior to the cam change, the engine idled at about 800-900 RPM's. After the cam change and once the over heating problem was resolved with the cam broke in, I let it seek it's own idle level. This was 1500 RPM's. Wondered why?? Nothing but the cam changed and I didn't think that would be any affect on the idle. So, I brought the idle down to the 800-900 range. Then the problem began with the engine dying when I removed the vacuum advance line. I think I should have left the idle at the former 1500 RPM's, unhooked the line and gone from there. It probably??? would have stayed running and I could have turned the distributor to set the timing. I'm pretty sure by turning the distributor, the idle gets affected. If this engine needs more advance, I can turn it almost a 1/4 turn clockwise before hitting the firewall. Anyway, that is my thought. Someone kindly tell me I'm completely wrong so I can move on. Maybe too much caffeine, Carmine.
Trying to compare the idle rpm with the old cam and new cam is like comparing apples to oranges in my opinion, more so with the timing not being set to spec yet. Without making any adjustments to the carburetor, once the timing is set correctly, my guess is the engine will idle much higher than with the old cam, but until the timing is set correctly, you will not know. Another guess is that you will probably have to advance the timing 10-15 degrees from where it is now to get close. But this is only a guess. Good luck Carmine, I know you'll get it.
See, this is what I don't understand. Another mental block. If I need to advance the timing on the distributor, why can't I just turn it?? I have almost a quarter turn clock wise which might be enough. Not sure why I have to pull the distributor and turn it clock wise one tooth. I will do that and whatever else is necessary to get it right, Carmine.
I would try and just turn the distributor first.
Guys, not explaining myself properly again. My apologies. With the motor running and vacuum advance hooked up, at about 800-900 rpm's, I'm at 12 degrees advance. The
vacuum canister is right against the heater hose inlet in the head. If I force the vacuum canister somewhat against the rubber heater hose, going in the counter clockwise rotation, I can get the timing to 14 degrees. I know it's not the way to measure timing with the line hooked up, but I just wanted to mention what my experience was. Going clock wise I have a good quarter turn which is what I think I need. At keast in that direction. Hope I explained this better. Many thanks, Carmine.
Carmine, why do you have your vacuum source as constant. Most vacuum set up's in these older car's where as having no vacuum at idle, and then vacuum increases as the rpm goes up.If you can show a picture of your carb port's that would help to select that port. Set your base timing with vacuum hose disconnected and then go to a ported source and see what that does. If you cannot set timing without advance pot hitting something you can just remove distributor and turn back a tooth. You could also move all the plug wires back one hole on the distributor if you don't care about the number one cylinder to match the cap number one . Also most advance unit's can be set for total advanced timing by inserting allen wrench in advance port and setting the stop. You would do this with a timing light once you have everything else ironed out, but if it don't ping on acceleration it might be close enough anyway
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Those cars,when new,had points ignition and a smog curve in the distrubitor.His engine now has an aftermarket HEI which more than likely has a more aggressive curve in it in addition to the aftermarket cam.Hook the vacuum advance up to manifold vacuum,it'll work better.Carmine,it order to advance the timing,which is what this engine needs,you must move the dist.body or the wires in the opposite direction of the rotor travel.If the dist.rotor moves during it's travels in the counter clock wise direction,to advance the timing,,you must turn the dist.body/wires in the clockwise direction.
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I have ported on my Hei on two different vehicle's with no problem's Don ,and it work's as it should. 
it has good advance as rpm's go up.?????To me manifold vacuum really don't do anything for timing advance once engine is started ????Start engine it advances it ,then what???? If you accelerate hard vacuum goes down for a while. Same as metering rods on a carb, accelerate and metering rod's come up by spring action to enrich the carb for more power. So if you accelerate hard the vacuum goes away for a moment and advance fall's back. Give me a lesson Don.
it has good advance as rpm's go up.?????To me manifold vacuum really don't do anything for timing advance once engine is started ????Start engine it advances it ,then what???? If you accelerate hard vacuum goes down for a while. Same as metering rods on a carb, accelerate and metering rod's come up by spring action to enrich the carb for more power. So if you accelerate hard the vacuum goes away for a moment and advance fall's back. Give me a lesson Don.
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I've found that it depends on your engines compression and or the cam..If you're running fairly high compression[9.5 plus],and a near stock cam,ported can work ok.Once the engine is at an idle,on manifold vacuum the vac.advance will be all in,and drop off as the vacuum decresses under load.This tends to improve low speed responsivness and cruising mileage.
Mine are both stock cam's so mine fall's into ported vacuum .
A lot of good thoughts and suggestions here. I appreciate each and everyone.
My vacuum for the advance is ported from the manifold. I'm not sure why except I read that it works best from this source. There is a carb. port for vacuum that I have a plug on. Not using it for anything.
Tomorrow, I'll be out in the garage and I'm going to try the simplest suggestions first. I want to make sure that what I see is exactly as I have explained. Will warm up the motor some, then turn the distributor counter clockwise, tightly up against the hose inlet, to make sure that this increases the timing degrees. That's the way I previously explained and want to make sure it is. Then I'll go from there. The last thing I want to do, is pull that distributor, but will it I have to. If anyone can stand one more comment, here it is. My distributor turns counter clockwise, opposite of Chevy. My firing order is the same as Chevy; 1-8-4-3-6-5-7-2. I have #1 and all the other cylinders marked in the cap. So, if I decide to move the engine wires in the cap, I would do this in the clock wise rotation since my rotor moves counter clock wise?? For instance, my present #2 in the cap would become my new #1?? And present #8 would be moved to the former #1 position?? Then I would just follow the firing order around the cap as usual. Would this be correct?? Thanks, Carmine.
My vacuum for the advance is ported from the manifold. I'm not sure why except I read that it works best from this source. There is a carb. port for vacuum that I have a plug on. Not using it for anything.
Tomorrow, I'll be out in the garage and I'm going to try the simplest suggestions first. I want to make sure that what I see is exactly as I have explained. Will warm up the motor some, then turn the distributor counter clockwise, tightly up against the hose inlet, to make sure that this increases the timing degrees. That's the way I previously explained and want to make sure it is. Then I'll go from there. The last thing I want to do, is pull that distributor, but will it I have to. If anyone can stand one more comment, here it is. My distributor turns counter clockwise, opposite of Chevy. My firing order is the same as Chevy; 1-8-4-3-6-5-7-2. I have #1 and all the other cylinders marked in the cap. So, if I decide to move the engine wires in the cap, I would do this in the clock wise rotation since my rotor moves counter clock wise?? For instance, my present #2 in the cap would become my new #1?? And present #8 would be moved to the former #1 position?? Then I would just follow the firing order around the cap as usual. Would this be correct?? Thanks, Carmine.