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I have no chance getting it that low. When I initially fired up the engine first time, the idle mixture was very rich (primaries set way open, exposing transfer slot). This made me able to idle at a lower RPM. Would low vacum engines take a richer idle mixture?
I don't have to put much effort keeping it standing still. The converter has a advertised stall speed rating at 1800 RPM.
I degreed the camshaft when installing it.
I do have the T-port sync set.
I run the M/E Wagner dual flow adjustable PCV valve in fixed orifice mode (due to the rough idle/low vacuum). If I remember correctly I'm pulling roughly 12 inches of vacuum at idle.
Initial timing set at 24 degrees. Could it be that this engine would run with locked timing? I'm at the DCR limit for pump gas.
I just recently modified my carb for idle bypass through the center of the main body. I haven't done much testing after this, because I have to fix some clearance issues between water pump and radiator first.
something is not right.
Actually that is being kind.
Ok,This is what I would do;
I would;
Disable the vacuum advance system. Close your home made idle air bypass. Reset your fancy PCV system to what the factory system would pull,or I would Temporarily plumb in a Factory PCV.Make sure the bowl vent is open.
Then I would;remove the carb, back out the curb idle screw until the primaries are fully closed,keep it there with one hand and flip it over. Then I would screw the curb idle screw back in until the Transfer slot exposure is square to a little taller than wide. I would not touch this screw again, for the rest of this post. I would Close the mixture screws to 2 turns on any carb but a Holley. On a Holley close it up to 1 turn. I would make sure the secondaries are closed up tight,and that there are no holes drilled through any of the throttle blades.
I would disable the power brake booster and plug all non-essential vacuum taps.
If you have adjustable valves I would reset them all to 1/2 turn lifter preload with that hydraulic roller.
I would Put a vacuum gauge on it,Put it in neutral, and chock the wheels or set the park-brake, or both,lol.
I would check the oil and coolant levels.
I would make sure the choke works
I would hop in,recheck that the tranny is in neutral, and start it up.
Then I would let it warm up, on a fast idle of about 1400.
While that is going on I would prove that on a metering rod carb, as soon as the engine starts, those rods are sucked down and stay down.
After the engine is warmed up, I would kick off the fast-idle, then back off the idle-timing to 14/16 degrees. Then I would check the tach and the vacuum gauge.
Now, if the engine stalls; I would Jack up the rear end and get the tires off the ground,using jackstands, then start her up again, still in Neutral. If it stays running now and the wheels are going round and round, something is wrong in the tranny, or in the TC. I would Apply the brakes.If the engine stalls again, I would replace the TC.
>But if the above made no difference, and the engine won't stay running, Then I would look at the vacuum gauge again. The supplied carb and ignition settings should have gotten her a nice idle at 750ish, and I have no idea about how much idle vacuum that cam should pull, but I can guess around 10 or perhaps an inch either way. If it's not there, I would start her back up and set her on one of the fast idle cam steps; the lowest that keeps her running. then I would go hunting for a vacuum leak. The first place I would look is on the bottom of the intake. I would flip the PCV valve out of the valve cover, and seal all openings into the crankcase. I would re-plumb the Vacuum gauge to the dipstick tube. I would start her back up still on the fast-idle cam, and watch the gauge. If I see a vacuum develop on that gauge, I'll be pulling the intake off, to fix it. If I can't find a flange leak, I will be checking the intake for porosity.
But if no vacuum shows up on the gauge, and the CC is fully sealed, then I would be checking all the usual places for leaks.
> But if the vacuum in the manifold, as initially checked, WAS 9 inches or more;Then I would be looking for a rich condition. I would first look down the primaries and make sure there is no dripping going on in there. If I see it, that will be corrected now.
Then I would pinch the rubber fuel line, and wait, watching the tach. If the Rpm goes up, then the fuel level is too high. If the rpm immediately begins to fall, then it is too low. If it stays the same for about 30 seconds and then begins to drop, then it is just right.
So then I would fix the float level, if required.
Let's say the engine still will not stay running on the provided settings; Something is still wrong.
So next will be a compression test. If you really are at the limit for pump gas, then with iron heads your compression should be about 165psi, and if aluminum, it should be 185 to 200. Of course,ideally,every cylinder will be the same.
Lets say they are all the same but nowhere near those numbers. The next test will be a quick-test to see if you got the cam degreed close.
The quick test is just to see about where the centerline is, and if I need to dig deeper. So off comes the passenger side valve cover and all the rocker gear, leaving the pushrods alone.. I would put #1 on TDC compression. I would go to the #6 pushrods, and stick a piece of masking tape on one of them where it was easy to see from the manifold side. Then I would pull out those two #6 pushrods and keeping them properly oriented, I would wrap a strip of masking tape around each one, at that chosen position.Then I'd lay them side by side, make the bottom ends flush and draw a line across both strips at 90* to the tubes. Then I would drop them back into their respective lifters, and orient them so I could see the marks, and so that they are in their normal working positions. Now, I would eyeball those marks. They should be near to perfectly on the same line. If they are not, then I would reorient the crank up to 10 degrees either way until they are.If it takes more than 10 degrees, Then the install is probably wrong, and the next move is to pull the front off and I am looking at a do-over.
This is a 107 cam right? The install is plus 4* right? So the installed center should be 103* right. Which is 4 degrees advanced. Ideally with symmetrical lobes, I would be looking to see 4* advance on the damper. With Your cam the lobes are not symmetrical, so the lines might not line up at 4*, but certainly by 10* I would think. If the damper goes into retard then for sure the front is coming off.
But let's say the quick test is right on.
Then There is nothing left to check, your engine is possessed of the devil, and you will have to set it on fire,lol.
Ok wait.That's a joke
So let's revue.
So far we have proved the carb is not flooding, that the fuel level is correct,that the bowl vent is open, and that there are no vacuum leaks. We have returned the carb to stock settings. We have set the T-port sync, and established a reasonable base timing. We have proved that the engine is healthy, and the cam is in correctly. About the only thing we haven't checked is the ignition system.
So the next thing I would do is put the engine back together,then I would put the timing lite back on and start her up on the fast idle cam. Now I would shine the light on something shiney, and kick the fast idle off.I would be watching the strobe as the engine slows and stalls. It better be strobing all the way. If it does then That's good. Next is the plugs; are they the correct reach plugs?
If yes then I am stumped.I have done all that I know how to do.
One thing I am almost 100% sure about; if your car was in my shop, we would get to the bottom of it real quick. Certainly a lot quicker than it took to type this post out,150 minutes.
Another thing I know is that your cam cannot possibly have a seat to seat longer than the 292/292/108 cam, and I have had no trouble tuning for it, in a healthy 367.
You can jump into my program at any point, that you think applicable, skipping the parts that you are sure about. but if you get to the end and it still won't idle at 750, well, you might have to start over.
Special notes;
I would not exceed 18* of idle timing.
The more timing you give it, the higher will be the idle, and vise-versa.
When you get stumped, pinch the correctly plumbed PCV line , and remove the valve. Slowly allow the carb to draw air there. The idle-speed should immediately begin to rise as you introduce the air.It should reach a maximum, then the engine will run ugly and finally at full opening it should slow-down and stall. That is what it should do. Now put the valve back in. It is your job to give the engine the idle air it wants. If the idle gets too high now, then reduce the idle-timing. If the idle timing gets lower than 14*,stop. Take away air instead to get the idle down. When you finally get back to 750ish, Revisit the mixture screws; making sure they fall into the correct range of about 3/4 or a bit more for a Holley, and 1.5 to 2.5 on almost any metering rod carb..At this point,You can change the curb idle setting 1/4 to 1/2 turn in either direction to correct the idle mixture screws.
And finally, check the Neutral to Drive, and Neutral to Manual-Low engagement, with the brakes applied.
