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| | | | Joined: May 2008 Posts: 194 Shop Shark | | Shop Shark Joined: May 2008 Posts: 194 | Asuuming you take a delco V8 distributor out of the engine and then put it back in and was one cog left or right of the original position what difference would that make?
Right I know it would either be retarded or advanced depending on which way you were off but if you then go a re-time it and get it back to 8 degrees BTDC is it OK?
Or is it not really at 8 degrees BTDC and is just faking you out?
I assume that it is still OK but that the position of the distributor is just rotated more one way of the other to get it back to 8 degrees.
Or is it just always going to be wrong?
Byt the way the 1957 shop manual says 8 degrees BUDC. What is BUDC (Before ? Dead Center) versus BTDC (Before Top Dead Center)?
On a V8 what is the easiest way to get #1 cylinder to TDC and know that you are there without removing valve covers?
Pull all the plugs and then can you turn it by hand or with a wrench or will it still be to hard to turn?
| | | | | Joined: Jul 2004 Posts: 5,708 'Bolter | | 'Bolter Joined: Jul 2004 Posts: 5,708 | svwilbur,
You are right on in your thinking...if you install the distributor a tooth off either way, it doesn't make a bit of difference as long as you can rotate the distributor enough to make up for it. The vacuum advance usually limits this rotational travel as well as the cut length of the plug wires. Sticking it back in the 'right' spot is for your convienience...so you have equal rotation either way.
I'm not sure what your manual is trying to say! There is Before Top Dead Center, BTDC and Top Dead Center, TDC and After Top Dead Center, ATDC, but that about covers all the bases.
If you chalk the timing mark on the crank pulley, pull #1 plug and tap the engine over with the coil wire removed, you will hear air rush out of the plug hole and you will see that chalked timing mark rolling up to the timing tab. When it on 0 degrees, that is TDC.
Stuart | | | | | Joined: Feb 2002 Posts: 12,029 Cruising in the Passing Lane | | Cruising in the Passing Lane Joined: Feb 2002 Posts: 12,029 | Before Upper Dead Center is the way the factory viewed it  Bill | | | | | Joined: May 2008 Posts: 194 Shop Shark | | Shop Shark Joined: May 2008 Posts: 194 | Thank you both for your quick answers to my questions!
That will help save me some work. | | |
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