Diameter of harmonic balancer? - Timing problem

[limey66]

OK, I'm sooooo close to getting my 289 2V V8 started in my '66. Whilst setting the valve clearances I noticed that I only have TDC marked on the balancer, and that is very feint. I've picked it out with some yellow paint, and the pointer on the timing chain cover, but I need to know where 6deg BTDC is, and there's no marks.

Had I thought about it, I could have measured the pulley so I can draw up a scale, but now I'm an hour's drive (each way) from the car until next weekend. Anybody know the outside diameter of a bone stock balancer, so I can draw me a scale and stick it on?

 

[jerry S]

OK, I'm sooooo close to getting my 289 2V V8 started in my '66. Whilst setting the valve clearances I noticed that I only have TDC marked on the balancer, and that is very feint. I've picked it out with some yellow paint, and the pointer on the timing chain cover, but I need to know where 6deg BTDC is, and there's no marks.

Had I thought about it, I could have measured the pulley so I can draw up a scale, but now I'm an hour's drive (each way) from the car until next weekend. Anybody know the outside diameter of a bone stock balancer, so I can draw me a scale and stick it on?

can't you just get a timing tape? Regarding TDC, just because your timer points there doesn't mean it is there. I relied on this on my stock balancer and was more than a few degrees off. I got a piston stop and found out where the real TDC was (in the neighborhood of the scribed mark but not even close enough for government work). Get a tape and a piston stop. it's a 15 min job tops.

 

[D.Hearne]

Each degree is about 1/8" apart, 6 degrees BTDC should be about 3/8" to the right of TDC ( looking at the motor from the front of the car) Most small blocks run better set at 8-12 degrees BTDC though, depending on your motor's octane requirements. Sometimes you'll need higher octane, with more timing.

 

[FORCED2DV8]

Each degree is about 1/8" apart, 6 degrees BTDC should be about 3/8" to the right of TDC ( looking at the motor from the front of the car) Most small blocks run better set at 8-12 degrees BTDC though, depending on your motor's octane requirements. Sometimes you'll need higher octane, with more timing.

Yeah I agree, Sometimes the best timing isnt always on a mark, so get something to make a refence off from and go from there.

 

[10secgoal]

Tape would work. Or you could find TDC and use an adjustable timing light. That way you only need the TDC mark

 

[limey66]

can't you just get a timing tape? Regarding TDC, just because your timer points there doesn't mean it is there. I relied on this on my stock balancer and was more than a few degrees off. I got a piston stop and found out where the real TDC was (in the neighborhood of the scribed mark but not even close enough for government work). Get a tape and a piston stop. it's a 15 min job tops.

OK, timing tape sounds like a good way to go, but don't I need to know the diameter of the pulley / balancer so I get the right tape, or does it come in different spacings for various diameters in one pack?

I'm getting the feeling that 6 degrees is a little too retarded, I'll be using 96 RON unleaded, what do you suggest?

 

[jmenke]

you could try to tune the engine using vacuum instead of timing marks.
this usually gives better results, as the pressed on wheels of the harmonic balancers can be off.
adjust the distributor to the highest vacuum reading at idle, adjust later as needed to keep from pinging while driving and accelerating

 

[jerry S]

OK, timing tape sounds like a good way to go, but don't I need to know the diameter of the pulley / balancer so I get the right tape, or does it come in different spacings for various diameters in one pack?

I'm getting the feeling that 6 degrees is a little too retarded, I'll be using 96 RON unleaded, what do you suggest?

unless I am mistaken, and I frequently am (You know my motto; "Often in error, never in doubt"), your stock balancer should be 6 3/8" in diameter. The tape from Summit for your application is $5.95. If you want to save on Summit's international handling charges and mailing costs ($34 for a $5.95 part), you can have it sent to my wife's hotel in portland and she can mule it back on Nov. 18th with the rest of her consignment of parts I am having her bring back for myself. I would then drop it in the mail to you ordinary postage from the NL to UK. I don't know how fast you need it though. PM me if interested.

the part number is SUM-163594

 

[limey66]

Thanks for the kind offer Jerry, but I was hoping to do something for this weekend - hence I was hoping to knock something up on CAD.

Anyway, NPD list the balancer as being 6 5/16" diameter, so what's 0.0625" between Stangers?

Any more ideas on what I should be setting my timing at anyone?

 

[D.Hearne]

Thanks for the kind offer Jerry, but I was hoping to do something for this weekend - hence I was hoping to knock something up on CAD.

Anyway, NPD list the balancer as being 6 5/16" diameter, so what's 0.0625" between Stangers?

Any more ideas on what I should be setting my timing at anyone?

Generally the more timing, the better, start at 12 degrees BTDC and go from there. If it pings, back it off till it stops. If it doesn't, add more till it does, then back off some.