I have a 1967 coronet with a 383 I did not build the engine I bought it like this When the number one cylinder is at TDC the zero mark on the balancer lines up with the pointer. But when I start the car the timing marks are so far advanced that they dont even come close to the pointer. On my timing gun it reads 22 degree of total advance but when you look at the the marks on the balancer it is far more advanced than the gun. The car runs sounds good and runs ok. Can the gear for the distributor be off one tooth? Or does this mean that whoever built the engine made a mistake and did not align the crank and the cam correctly? Or am I missing something ?
Thanks

 

Are you disconnecting your vacumn advance hose from the dist when you check timing? You need to. I run my 451 with about 20 degrees of initial advance. They seem to run better that way. Then when you rev the motor, it should move even further in the advanced direction. This is centrifugal advance kicking in. Run a total of about 38 degrees at 3000 RPM. You may need to get a timing tape to get the mark in the right spot on the balancer. Then when you rev it, that 38 * mark should line up with your tdc mark on your timing cover.

 

1 How did you determine that TDC is correct. If you didn't use something like a piston stop, or a dial indicator when torn down, you cannot make that assumption.

2 I don't trust "dial up" timing lights. With that said, you either need to degree your balancer, or buy timing tape for the correct diameter balancer

Degreeing a wheel does not have to be complicated. After determining TDC FOR SURE carefully measure around the OD of the balancer. Then figure how many "degrees per inch" around the wheel.

Figure how many inches 40* is, and CAREFULLY measure this from the balancer TDC mark using a flex tape. You can NOT make this first measurement with dividers. Use a small square and scribe to mark the wheel

Now you can go to dividers if easier.

Divide the TDC to 40* mark in half. You can easily check this from one end to the center. Mark this, your 20* mark.

Now divide the 20 into 10, and again, you can easily check this for accuracy

So now you have from TDC out to 40 in 10* marks. Now take your dividers, set on 10, and make one or two more marks out past 40 for 50 and maybe 60 That way, you can also check your vacuum advance

Last, you can establish 5* marks and add them in if you like

Scribe them several times, file the important ones deeper, such as 35 and 40, and probably 10, 15, 20

The current thinking with an engine with ANY kind of performance cam, even a "stocker" factory HP cam, is to run LOTS more initial than we used to.

You can run initial up in the 12-15, even 20* on some engines, so long as it does not "kick" the starter.

Idle the engine down as much as you can, and set initial timing for highest vacuum reading, or highest RPM idle. You will have to adjust the idle screws back down twice or more to keep things in reason. CHECK by starting several times, that it does not kick on the starter.

NOTE that reading. That is your new initial setting.

Then with the vacuum disconnected, experiment for best power band and high end. This is usually anywhere from 32-38, on some engines 40 depending on head design, compression ratio, camshaft, fuel quality, and a few other things.

Once you get that set, you need to go back and see where initial "landed". The difference in degrees between this last initial reading, and the first one you set, is the amount you need to change the curve in the distributor.

 

I did not build the engine. The way I determined if the motor was at TDC is I removed the valve cover on the number 1 side and turned the engine over until both the intake and exhaust valves were closed. I bought the harmonic balancer from 440 source it has clearly marked numbers. I have a MSD distributor it does not have vacuum advance. How do you use a piston stop? thank you

 

I also read about putting as much timing in as soon as possible. I have the MSD 8545 distributor I am running the silver springs and the red advance stop bushing which gives me all the advance at about 2800rpm.

 

I would bet that the 440 Source Dampner marks are wrong. I think I remember mine where backwards or upside down. With number one piston way down in the hole you screw you piston stop in the #1 sparkplug hole. Rotate your engine by hand clockwise until the piston hits the stop. Mark that postion on the dampner with a piece of tape. Rotate the engine counter clockwise until it the piston hits the stop again. Place another peice of tape at that spot. Your top dead center is in the center of the two peices of tape.

 

Brem is right. There is only a couple of ACCURATE ways to determine TDC, and watching the camshaft is not one of 'em.

The only accurate PRACTICAL way, ---and it's cheap, easy, and takes only a few minutes-- is indeed a piston stop

 

Thanks a lot you were right the timing marks were off by 17 degrees I used the piston stop and found the real tdc I am going to buy the timing mark tape so i can place it over my nice expensive harmonic balancer marks.
Thanks for the great advice and have a great day!

 

what if the cam was advanced or retarded how could you know that ?

 

???eh???

 

Only buy taking the timing cover off.

 

Hi Gorts, To accurately determine cam timing you need a degree wheel, a positive piston stop, a dial indicator, cam spec card, and a little knowledge with alot of patience. Also access to the lifter valley. The procedure is outlined in many of the car magazines from time to time. C Ya

 

got a nice one does the trick
jst waiting for some one to touch on that

 

My guess would be the wrong application.. Early 440 and later 440 when the changed the location of the water pump outlet I think Required different timing markers

 

Or Hecho en China.