[PontiacHO]

Been a long time since I’ve done any engine work…..
If the timing gear marks are together, that’s firing on number 6 and if the cam gear mark is at 12:00, that’s firing on number 1.
Do I have that right?

[steve25]

All that matters gear dot wise is knowing where to point the rotor when you drop the Distributor in.

If with the number one piston at TDC you see the exh valve on cylinder 6 open some then your rotor should point where you want plug wire for number 1 to be on the cap.

[johnta1]

If the timing gear marks are together, that’s firing on number 6 and if the cam gear mark is at 12:00, that’s firing on number 1.

Yes

Then you can double check the way Steve said, if you want to.

[PontiacHO]

Thanks

[steve25]

Note that when you do drop the distributor in at first it will likely not sit all the way down in the block as it should.

This is due to the oil pump drive shaft not being lined up right.
Don’t fret about this.
All you need to do is install the hold down clamp such that the distributor can not rise up any more then 1/8” from the way it is sitting ,then next just crank the motor over for 2 revolutions and the distributor will then drop into place as it should be.

[Sprocket]

Originally Posted by PontiacHO

Been a long time since I’ve done any engine work…..
If the timing gear marks are together, that’s firing on number 6 and if the cam gear mark is at 12:00, that’s firing on number 1.
Do I have that right?

Yes, that's how it is shown in the factory shop manual, but always double check your valve events.

[PontiacHO]

The distributor was clocked with the vacuum advance on the passenger side of the engine (like a Chevy). I know that isn’t how Pontiac built the engine originally. I prefer it clocked like a Chevy. Seems to be easier to adjust distributor, connect-disconnect vacuum hose for timing, and is in a convenient position for my HEI wiring connector. Outside of not being visually correct (factory), does it matter how the distributor is clocked? Having the larger HEI distributor-cap, it would bury the vacuum advance deeper behind the intake (brake booster) on the factory side. Thoughts??

[grivera]

As far as functionality, it doesn’t matter which way you position the distributor or where on the cap you place number 1 for that matter. You’ve already accounted for the clearance to accommodate the vacuum can. If you’re using ignition wires that were customized for a particular configuration it will be a challenge if you deviate from said configuration .

[steve25]

Pontiac motors have the vac can on the drivers side due to the heater hose back there on the passenger side limiting the swing range that you end up with.

[PontiacHO]

Understood. It seems that using the GM HEI unit makes the factory clocking less advantageous. My heater hose is looped out of my way so I reckon I’ll carry on as it was originally on the passenger side.

[GTO-relic]

Originally Posted by PontiacHO

Been a long time since I’ve done any engine work…..
If the timing gear marks are together, that’s firing on number 6 and if the cam gear mark is at 12:00, that’s firing on number 1.
Do I have that right?

best way to install timing chain, and distributor, is:

1. line up timing chain dots in center between crank/cam gears.

2. valve covers off, turn engine by hand with socket on balancer bolt, until you visually SEE the intake valve CLOSE on #1 cylinder, front left hole, drivers side of motor. continue turning until mark on balancer lines up with zero on timing cover.
NOW you are at TDC #1 compression stroke, visually verified. you can drop your distributor in with the rotor tab pointed at where the vacuum advance bracket is attached to the distributor, which is where #1 post is on cap when installed. before you drop it in, turn the shaft to back off the gear a tad, because the distributor shaft TURNS slightly as it's dropped in. drop it in once you can watch it turn, then pull it back out, give it the lead it needs, to drop in and turn, and be right at the vacuum advance bracket, where it meets the distributor. you want it pointing at the vac. advance bracket, with enough free adjustment space remaining, to allow advancing it clockwise to time it later, as need be.

3. once dist. is in pointed at vac. adv. bracket, SLIGHTLY turn the distributor a "smudge" clockwise, INTO the natural distributor rotation to advance it a bit, so it starts easier. snug up the dist. hold down bolt. Pontiac rotates distributor counterclockwise. if you have it pointed directly at #1, the timing is retarded, you want 10-15 degrees to start it quick. then you can time it with a light.
you can crank engine with no fuel to time it with light, before you even fire it.

4. if you want to do a check after dropping in the distributor, turn the crank 1 more revolution 360 degrees, the rotor tab should be pointed at #6, you are now on TDC #6. continue turning another revolution back to TDC #1.

5. when timing a Pontiac, you can attach the high voltage inductive lead to either #1 or #6, the timing will read the same either way. this actually helps because the timing indicator on the block is on the passenger side anyway. you can clip right onto #6, and have the +/- leads of the light going across top of radiator support to battery- with no timing light leads over the motor, dangling in the fan, pulleys, belts, carb linkage.

6. if you're looking for TDC #1 and you're turning the motor and see the EXHAUST VALVE just close on #1, you are at TDC #1 EXHAUST STROKE- and also at TDC #6 intake stroke. CONTINUE TURNING until the intake valve opens/closes on #1.

7. don't worry about the timing gear marks after you line them up. if they're lined up in the middle, that's good. however, before you go dropping in the distributor, if you had just put a new cam in, you should DEGREE THE CAM first. if you don't want to, then at least put a 2 degree offset advanced cam key in- because the chain gives up a degree almost instantly. this is why you really should DEGREE IT with a new cam, to the cam card.

[tom s]

Once you have the chain on,just put a cork in Pontiac number one,front on drivers side.Put a cork in the spark plug hole and rotate with breaker bar until it shoots across the garage.Tom

[GTO-relic]

thumb in the spark plug hole works too, but it pumps air on compression and exhaust stroke, just less on the exhaust stroke. watching the valve there's no miss.

[PontiacHO]

Thanks all. It’s amazing how quickly things get cloudy after being away from this so long. In the late seventies and until mid-eighties I turned wrenches at a Chevy dealership. Then 40 years since moved into another career. Built a big block Chevy around 2005 but that was a Chevy. A few differences in Pontiacs like the water pump plates, timing cover that has to be free of corrosion etc, valve adjustments (will use poly locks), different valve seat angles, opposite distributor rotation, blind head bolt holes, ported instead of live advance vacuum, and them hard to get to exhaust manifold bolts!! I love my Firebird and anxious to get it running like I want it to.

[OG68]

And don't forget the hidden oil gallery plug.

[GTO-relic]

Originally Posted by OG68

And don't forget the hidden oil gallery plug.

I know someone who got burned by that one, 40 years ago....Ford shop took the plug out, but didn't put it back in again, and put the outer small soft plug back in only. no oil pressure in the top end of motor at fireup. He told the shop he's coming down to throw the block through their front window.,

[steve25]

This is why with any shops built but untested motor even if you have to yank the Distributor out you do so to look down that hole and confirm that the pipe plug in there.

[OG68]

Last second check after completed engine is loaded in the truck

opps...

[pngoat]

I know that pontiac distributors rotate counterclockwise. Is that as viewed from the top (rotor) end?

[johnta1]

Yes.