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starin 07-16-2012 11:53 PM

Installed pontiac 350 timing gears wrong
 
Hi there all,

I really need some help please, i installed an edelbrock double roller timing chain set on my 1972 pontiac 350, its my first rebuild and i installed the cam gear with the dot at 6 oclock and the crank gear at 12 oclock like a chevy engine. I didnt realize that it should have been 12oclock on both. I ran the wires and stabbed the distributor with it on the number one cylinder and couldnt' figure out why the car was so low on power and would only idle decent when the timing was set at 18 degrees plus it got hot. Well with enough research i found out i put them in the wrong way.

I understand that i am now 180 out and should set my number # 1 cylinder in the traditional # 6 position. however what will my firing order be now? I need some help figuring this out so i can run my wires from the cap to the proper cylinders. Your help is greatly appreciated.

this is in a 1968 firebird with a pontiac 350 still using the original points distributor.

Thanks in advance!

cobalt327 07-17-2012 01:40 AM

Quote:

Originally Posted by starin (Post 1574489)
Hi there all,

I really need some help please, i installed an edelbrock double roller timing chain set on my 1972 pontiac 350, its my first rebuild and i installed the cam gear with the dot at 6 oclock and the crank gear at 12 oclock like a chevy engine. I didnt realize that it should have been 12oclock on both. I ran the wires and stabbed the distributor with it on the number one cylinder and couldnt' figure out why the car was so low on power and would only idle decent when the timing was set at 18 degrees plus it got hot. Well with enough research i found out i put them in the wrong way.

I understand that i am now 180 out and should set my number # 1 cylinder in the traditional # 6 position. however what will my firing order be now? I need some help figuring this out so i can run my wires from the cap to the proper cylinders. Your help is greatly appreciated.

this is in a 1968 firebird with a pontiac 350 still using the original points distributor.

Thanks in advance!

If you installed the timing set as you normally would (crank at 12 o'clock cam at 6 o'clock), cylinder #6 will be at TDC firing. The distributor rotates CCW (opposite of a Chevy). The firing order is 1-8-4-3-6-5-7-2. #1 is driver side, front.

A diagram is here.

All you need to do is either the reset the distributor by turning the crank until the TDC lines are lined up, remove cap and distributor clamp, lift and turn the distributor shaft/rotor 180 degrees from where it is pointing. It will be pointing at either #1 or #6 with the TDC lines aligned. Which ever it is, point the rotor to the other cylinder's terminal).

Or swap the wires, making:
Position 6 on the cap = #1
#5 = #8
#7 = #4
#2 = #3
#1 = #6
#8 = #5
#4 = #7
#3 = #2

Mr. P-Body 07-17-2012 07:35 AM

I know we've been "down this road", but it cannot be stressed enough. You did NOT install the gears incorrectly. You installed the the distributor incorrectly. "By the book", the settings are 12/12 for BOTH Pontiac AND Chevy. While it may SEEM "easier" to install them ar 6/12, it really isn't once you understand "where you're going". But when you DO put it at 6/12, rotor points to #6, as others have stated.

Please, this is not a point of "contention", but a point of service. I've seen more confusion over this specific issue on these "hobby" sites than any other.

Jim

T-bucket23 07-17-2012 01:12 PM

If it started and ran you are not180 out. As the others have stated as long as the dots are actually lined up the cam can be at either 6 or 12. If you are 1 tooth off that can cause power issues. I would double check everything else before taking it back apart.
Verify the timing pointer and damper TDC using a piston stop. Make sure the exhaust is not restricted, etc.

If you have the cam card you can check to be sure you are not a tooth off on the timing chain without taking it apart. Put a dial indicator on #1 intake and rotate the engine. Compare the cam card spec to the actual valve opening.

starin 07-17-2012 10:24 PM

well the car definitly starts and runs, but when i get on the gas it makes a lot of noise and theres really no power. I definitly put the cam gear at 6 oclock and the crank gear at 12 oclock. so right now the way i stabbed the distributor is with the rotor pointing at the number one cylinder driver side closest to the radiator and that is where my number one wire goes. Your it should start?

timothale 07-18-2012 07:23 AM

wire it by the book.
 
I had a Buick nailhead in my willys and put on a new Dist cap and Rotor, I had the Ford FE firing order and cyl numbering sequence memorized.( I worked for Ford) and wired it up the Ford way. It ran crappy but started and ran/ Some of the Cyl's were getting the correct spark timing. and of course some were not Number one and dist rotation were different but it ran.

T-bucket23 07-18-2012 07:36 AM

Quote:

Originally Posted by starin (Post 1574774)
well the car definitely starts and runs, but when i get on the gas it makes a lot of noise and there's really no power. I definitely put the cam gear at 6 o'clock and the crank gear at 12 o'clock. so right now the way i stabbed the distributor is with the rotor pointing at the number one cylinder driver side closest to the radiator and that is where my number one wire goes. Your it should start?

Sound like it is pinging. What kind of noise. Does it sort of sound like marbles rattling in a can.
As stated above, double check the firing order as well.
You could try kicking the timing back a few degrees if you dont find anything. I think you said you said you were starting at 18, go back to 12 or so and see if it gets better

WDCreech 07-18-2012 09:34 AM

Did you check the initial timing with the vacuum advance unhooked and the source plugged? If so what was it set at?

Bill

cobalt327 07-18-2012 10:39 AM

Something to check!
 
Quote:

Originally Posted by starin (Post 1574774)
well the car definitly starts and runs, but when i get on the gas it makes a lot of noise and theres really no power. I definitly put the cam gear at 6 oclock and the crank gear at 12 oclock. so right now the way i stabbed the distributor is with the rotor pointing at the number one cylinder driver side closest to the radiator and that is where my number one wire goes. Your it should start?

Be sure that the plug wires for #5 and #7 are correct at the distributor cap and at the spark plugs. The spark plugs and the distributor cap terminals are right next to each other- both physically and in the firing order. The Pontiac heads aren't as bad as a SBC for this because #5 and #7 spark plugs are separated by the center exhaust ports, but it is still a common occurrence. If they're transposed the engine will run, but it won't run well and it could be described the same way you are describing how your engine's running.

Then check and adjust the timing if needed. A performance advance curve is very important.

Mr. P-Body 07-18-2012 11:58 AM

Exhaust "between" 5 and 7? You're thinking of the Olds, not the Pontiac. The Pontiac has the same valve/port "layout" as small block Chevy, with a better intake port and a HORRIBLE exhaust port...

One thing not mentioned yet: Pontiac distributor rotates CCW, opposite that of the Chevy. Make sure the wires are installed accordingly.

Jim

AutoGear 07-18-2012 12:04 PM

Quote:

Originally Posted by cobalt327 (Post 1574501)
If you installed the timing set as you normally would (crank at 12 o'clock cam at 6 o'clock), cylinder #6 will be at TDC firing. The distributor rotates CCW (opposite of a Chevy). The firing order is 1-8-4-3-6-5-7-2. #1 is driver side, front.

A diagram is here.

Mr PBody;
Yes it was.

cobalt327 07-18-2012 12:43 PM

Quote:

Originally Posted by Mr. P-Body (Post 1574876)
Exhaust "between" 5 and 7?

I was looking at 3/5 and typing 5/7. My mistake.

starin 07-18-2012 09:39 PM

hi guys, to close the thread and help out anyone else that ever runs into this here is what i did. i basically took all the wires off, took cylinder # 6 spark plug out and spun the motor till it started compressing air and set it at tdc. then ran the wires from the # 6 cylinder and using it as number 1.

so now my firing order is 6-5-7-2-1-8-4-3 it now times at 12 degrees and runs decent. however i have another problem im going to post on a seperate thread.

Thanks for the help everyone.

cobalt327 07-18-2012 09:43 PM

Quote:

Originally Posted by starin (Post 1575051)
hi guys, to close the thread and help out anyone else that ever runs into this here is what i did. i basically took all the wires off, took cylinder # 6 spark plug out and spun the motor till it started compressing air and set it at tdc. then ran the wires from the # 6 cylinder and using it as number 1.

so now my firing order is 6-5-7-2-1-8-4-3 it now times at 12 degrees and runs decent. however i have another problem im going to post on a seperate thread.

Thanks for the help everyone.

Actually the firing order is still the same as it always was. To put it more accurately, you changed the location of terminal #1 on the distributor cap.;)

In any event, glad you got it figured out.

T-bucket23 07-19-2012 07:58 AM

Quote:

Originally Posted by cobalt327 (Post 1575052)
Actually the firing order is still the same as it always was. To put it more accurately, you changed the location of terminal #1 on the distributor cap.;)

In any event, glad you got it figured out.

This is correct, the firing order always starts on #1 cylinder.


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