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Discussion Starter · #1 ·
I picked up a 1965 Tempest that had a 326. The last owner had sold the original engine and let go of all the brackets and pulleys. A Chevy 350 conversion was started, never finished. I found a 326 engine to go back in.
Just with no brackets or pulleys. My plan is to add A/C at some point down the line but main concern is getting it up and running first. I want to do the pulleys now as if I had A/C instead of changing out pulleys later.
I found set of 65-66 brackets and a set of 67 pulleys for A/C car.
Also aftermarket pulleys which state they work for 64-68 so I am guessing that is for short water pumps.
So one would think that 67 pulleys would also fit on 66 brackets. And it appears the A/C belts runs separate from all other pulleys but the diameter of the pulleys is different. Some information I have gathered is to use all pulleys from the same year. Which is probably over kill though I do not want a shelf full of unused pulleys
Any first hand information would be greatly appreciated.
 

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Cameo Ivory 1967
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I don't know for sure, but I can tell you that there are many threads on this forum, created by members struggling with PULLEY ALIGNMENT. i'D WAIT FOR A PARTS PRO TO COMMENT. Sorry for the caps lock
 

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sure I will chime in ..
first... buy a GTO restoration guide ,,, 40.00 to your door
its a BIG help
I am not near my books till tonite for pictures
but
67 starts the 67-70 pump n pulleys and last year of the 6 bolt crank pulley
66 67 use and interchange some of the other 2 pulleys
ac and non ac pulleys dont mix
those early ac diameter original pulleys are gettin tough to find
the part number and diameters are listed in the book

scott
 

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you just need to dedicate yourself to the year you want it to
look like for the final product.. each year isbasically unique in their own ways
to the trained eye ...
some parts transfer to the next or previous years with revisions
ac pulleys are ac only
non ac non ac only
you want 65 stuff correct ??
 

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Discussion Starter · #8 ·
I found some interesting information with my searching.

All of the timing chain covers from 1964 to 1979 will bolt up and interchange with any motor from those years. However, you must use the matching water pump, pulley and crank pulley and brackets to avoid alignment problems with the alternator and/or power steering pump and A/C. All of the water pumps from ‘64-‘68 will interchange. These pumps have eight bolts and measure 3-5/8” long (from base to water pump pulley flange). The casting number for ‘64-‘65 is 9772716 and for ‘66-‘68 it is 4782482. The matching pulleys are 2” in height. From ‘64-‘67 Pontiac used a small diameter (5.25”) six bolt two-piece harmonic damper and from 68-79 a large diameter (6.75”), one piece four bolt damper was used. In ’69 Pontiac changed to an 11-bolt water pump but the early ’69 was different from late ’69-on. Early ’69 engines used a pump that measured 4” long (casting# 9796351) and the pulley was 2-1/4” in height. From late ’69 to ’79 only one pump style was used, it measured 4-1/2” long and there are at least two different casting numbers used: 482138 and 488296. Always use the correct diameter and style crank pulley to match the water pump pulley. The non-A/C cars used smaller crank pulley and a larger water pump pulley and the A/C cars used a smaller water pump pulley and a larger crank pulley. Also use the same series timing chain cover and balancer to properly line up your timing marks. The same timing chain cover was used for both ‘64 & ‘65 and had just a simple pointer. These were cast with number 9773371. The timing cover used on ’66 and ’67 employed a small timing scale marked -4, 0, and +6 and is otherwise identified as casting # 9783130. The ’68, ’69 and ’70 timing covers look very similar with timing marks of 0-6-12 degrees BTDC and accommodated the large diameter damper. The ’68 timing cover casting number is 9790347 and uses the 8-bolt water pump. The ’69-‘70 timing cover casting number is 9796346 and uses the improved 11-bolt pump. For ’71 and later the timing cover timing tab is marked from 4 degrees after to 12 degrees BTDC and is graduated all the way to 16 degrees BTDC. As compression ratios were lowered to 8:1 and lower there became a need for increased initial advance. Casting number for this cover is 482883. 71 and later crank and water pump pulleys are about 1/4” taller and the accessory brackets are set out to match. The 71 and later heads have an extra bolt hole in the front of the head toward the intake side that the alternator bracket uses. There is not enough meat in older heads to drill and tap the hole so it makes it hard to use the 71 and later brackets if you are using the earlier heads. To use the accessory brackets from the 70 and earlier engines with the 71 and later damper and timing cover and water pump you need the 68-70 crank pulleys and the late 69 and 70 water pump pulleys.
Many of the pulleys have the part number stamped on them.

These are the pulleys I plan on using 9782679 WP, 9782704 A/C add on, 9782680 CP
 
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