Engine Timing

[67Camaro RS/SS 350]

What would cause the timing to retard no matter which way the dizzy is turned? I got the motor back in and everything is installed, but when I go to time the engine, no matter which way I turn the dizzy, it retards and stalls. At first, I thought it may be 180* out, but after removing #1 plug, holding fingure over hole I felt the puff of air telling me it's on compression stroke. I then removed cap and it was right.

Also, my rotor is pointing toward #2 cylinder. It has been like this for some time now. At one point, it was pointing toward #1 cylinder, but recently if I tried to point it toward #1, I would have to turn the dizzy so far to get it to run that the vacuum can would hit the intake.

[CarPlayLB]

Where did you hook up the vacuum advance hose? Sounds like you hooked it up to manifold vacuum and the timed vacuum port!

[shep]

If it is not pointed at # 1 then it is off a tooth or more. Pull it and check for a damaged gear. If it is good then put it back in, in the correct position.

[67Camaro RS/SS 350]

If it is not pointed at # 1 then it is off a tooth or more. Pull it and check for a damaged gear. If it is good then put it back in, in the correct position.

I installed it having it pointing at #1 and the engine would not start. The only way to get it to start having it pointing at #1 is to turn the dizzy so far that the vacuum can hits the intake and even then, it's so retarded it barely wants to idle. The wires are custom fit and if I try to reset the wires, some of them aren't long enough and others are too long. It almost sounds like the timing gears are off, but it run too damn well to be that. The car runs great with it pointing at #2. If I look at my GM service manual, the wires are in the same positions as in the book. #1 and #8 posts make a "V" to the rear intake runner and the rear of the carb. If I move the wires to where they would need to be by rotating the dizzy, #1 post would be pointing at the master cylinder and #8 would be pointing at toward #1 cylinder. Completely wrong.

[MonzaRacer]

Ok, mark the cap and the distributor at number one. now pull the cap making note where you want the cap oriented.
Now rotate the engine till your up on number one, use a wrench to pull it up to the timing mark, set the TDC at around 12 to 16 initial and back the rotor up a couple of teeth. Take your time and watch your rotor, if the distributor doesnt sit all the way down simply hold dist in place and hand rotate engine till dist drops in, then back up to number one again.
making sure number one is lined up at distributor and timing mark is in the 12 to 16 degree range at timing tab. Then snug down the hold down. This should get you started then use a timing light to verify base timing.
I start pretty much in this area then adjust from there.
My tuning style is base for best starting ,yet advanced enough to achieve proper curve with centrifugal and vacuum advance.
Most wedge engines like static timing around the 32 to 36 (base timing and centrifugal added together)but tuning for best power is in this area. I advance base timing till I see either power loss or bucking the starter.
Now after dialing in these and adjusting the carb idle speed and mixture, THEN you hook up the vacuum advance to manifold vacuum, then readjust the idle speed, and only if needed you refine tune the idle mixture but it should be close.
Now the reason you use manifold vacuum is that at cruise is that it gives you mileage.
Tailoring your curve is how you make power and performance with mileage. some cars want a slower vacuum curve or less and this is achieved with adjustable vacuum can.
The total is this, initial+centrifugal+vacuum, and this can total up to 50-60 degrees advance. Too many people limit thier engines and hamstring them.
My 402 bigblock chevy runs 18 initial on 94 Sunoco and 14 intial on most 92/93 octane fuels, I have an HEI with stock weights but use 2 of the lightest springs on it and an unmodified centrifugal stop and manifold vacuum. This gave me one curve of 58 total and one of 54 and with little or no ping/knock(very slight in hot temps,but in winter I could run the higher with no issue) and in a 4000lb 70 Monte Carlo and 3:55 gears got 14 to 15 mpg.
My 355 roller runs 60 total, 18 initial and rest is in centrifugal with limiter modified and light springs, and with that engine(first incarnation)would make 18mpg in my 71 Monte with 2:73 gears and when switched to my 78 C10 it got around 14 to 16. After building newer 355 all fresh and new and better heads and all it still liked the same curve.
Too many people take timing out, or limit that and wonder why their engine gets crappy mileage.
I was taught to give as much timing as engine wanted to make best power THEN add in the vacuum advance for mileage. Most engines surprise me.
Also remember more timing = engine thinking its richer fuel wise. Old time tuner who taught me a lot explained it as this, the cam has over lap, the more advance the farther away from overlap the spark is and tada richer mixture as less "blow down" the timing will experience.
Good luck, hope I havent confused and if you need to ask a question just give me a PM.
Lee Abel
AFTERMARKET PERFORMANCE