View Full Version : Fan Pully, Z28 versus Big Block
12-29-2002, 01:03:00 PM
I have 1970 LA build sheet(there are NO Norwood 70 Buildsheets) that shows under Box 22/Fan pulley the code BV. I am also looking at my ORIGINAL Z-28 pulley that is stamped 3947824BV. Now I'm looking at 70 Assy manual page UPC Z-28 sheet A 6 and its shows fan pulley as part # 3976060. Now I also have two different 1970 L-78 LA build sheets that show a AP code fan pulley in Box 22, hoever my 70 Assy manual on page L-78/A7 shows the same 3976060 for the pulley. Can someone explain why assy manual shows same # for L-78 and Z-28 and then its a differnt # from
the 3947824BV that I have. I have another person with a 3995647AP that says its for 69 302, 70 Z28/454 & 71/72 Z-28.....please respond if you have these pulleys and an accurate source of facts.....Chuck Sharin/Rainy(but not Snowy)Seattle
12-30-2002, 12:09:00 PM
dont have an answer for you but my 70 has the 3947824bv pulley.car was 3rd or 4th week of june.
12-30-2002, 08:56:00 PM
Chuck, Don't know if this helps, but I have a
71 manual.UPC Z28 Sheet6K-1, shows fan pulley
# 3995647. However in the revision record,
this sheet was cancelled 8-14-70. I also have
a 70 Van Nuys build sheet showing BV code for
12-31-2002, 04:10:00 AM
This "Models thru 1975 chassis and body parts catolog" dated April 1983.......shows in group 1.062 ....72-74 All w/Sp. H/Per.(350) ........ 3995647
The Two Lines above this entry has ......
70-71 All w/Sp. H/Per (350,396,454)
neither of these two entries have any part # behind them.....WHY IS THIS??? Were they out of inventory by this 1983 printing....had it become discontinued.....anybody working in Chevrolet parts know how to explain these parts catologs?????
12-31-2002, 11:50:00 AM
Chuck- on my 1971 Z the pulley is 3995647 AP. My build sheet shows CG AP in a box labeled 'CRANK & FAN PULLEY'. The box number is gone but looks to be in the low 30's on this 1971 build sheet.
12-31-2002, 02:15:00 PM
Joey, So your 71 Z with the AP pulley is as the parts book says and the 69 and 70 Z's had the BV pulley .........now I just either have to check my own or hear from someone confirming that the AP was also on a 70 L-78........however I already have TWO buildsheets (LA) calling for AP fan pulley in Box22 (of build sheet).......MY NEXT QUESTION IS...What is an NOS in the Box AP pulley "worth" on average.....someone. anyone
12-31-2002, 05:43:00 PM
Camaro Parts book effective May 1981
3770245 67-68 302
3906656 67 396/375 HP-DUAL GROOVE
3905995 68 327,350 AND 396/325 OR 350 HP
3932456 69 302
3995640 69 396/375 HP SUP 3976060
330556 69-70 307,327,350,EXC Z28/ AND 396/325 OR 350 HP/EXC AC SUP 3989305
3995631 70 307,350 EXC/Z28/AND 396/350 HP/AND 400 WITH AC/SUP 3976059
3995647 70 350/Z28/AND 454
330556 71-72 307,350/EXC Z28/AND 400 EXC AC/ SUP 3989305
3995647 71-74 Z28 EXC AC
330556 73-76 305,307 OR 350/EXC Z28 EXC AC
4spd Z28's owned '68,'71,'77new,'78new,'80new,70 still,daily driver 87 G/N.
Home Page on 1970 Z28
Chevy's Baddest Toys
12-31-2002, 06:56:00 PM
chuck, i have looked at a lot of cars, and talked to a lot of owners, so i go by the 90% rule. if 90% of cars have it i take it as correct. 70' LS6 and L78 camaros, novas, chevelles etc.. all came factory with the 3976060AP water pump pulley. i have never seen this pulley on a small block car.(Z28).my L78 has the 6060 pulley. my 70' Z28 has the 3947824BV water pump pulley. i have an NOS in the box 3995647AP pulley, which i beleive is the over the counter replacement pulley for either of the above.once again, don't take this as gospel, its just what i have seen. hope this helps .mike i have also seen the 647 pulley on 69' cars. take it for what its worth and make your own decision. parts got put on whatever they were needed, so there is NO absolute.
1970 Z-28,1970 ss 350 SURVIVOR ,1970 SS396 L78,1972 SS396
[This message has been edited by THNDER (edited December 31, 2002).]
01-02-2003, 08:25:00 AM
I have heard that the early L78's, and LS6's had the 3947824BV fan pulley. Most of them came with the 3976060AP pulley. If you are in need of a 6060AP pulley, let me know. I know someone who has one, but he wants $300 for it. Let me know before this weekend if you anyone is interested in it. I will see him at the swap meet in Indy this weekend.
01-02-2003, 10:11:00 AM
Chuck- you referenced the 70 assembly manual RPO Z28, sheet A6 with regards to this pulley. On this page, it lists the pulley as item #1. Look at page revision note #5 which is attached to this pulley......
Sorta adds in an interesting twist, huh?
09-15-2003, 03:07:00 PM
Coming back to this subject as I now have received the N.O.S. "AP" pulley I bought some time ago along with other parts. I can report that dimensionally the AP and the BV pulleys are the same. The BV 3947824 is made internally a little different to be stronger and is heavier compared with the AP.
Interesting to me how my Jan 70 L-78 comes with an AP pulley (which is considered newer) and my July 70 Z-28 eng V0729CTB comes with the "older" BV pulley.....Anyway one or the other is correct....If this ever comes down to judging it will be confusing...but I do agree with Mike's 90% rule.
The old USCC had surveys from ALL the Misc Camaro owners stating what components were on your eng etc.....We need to compile these facts again.......
see ya, Chuck
09-16-2003, 11:22:00 PM
Here are the part #s off all the brackets on my L-34 motor;
3969917 Main A/C bracket
3969912 Rear lower A/C bracket
3969910 Rear upper A/C bracket
3969916 Front A/C compressor bracket
3969911 Rear A/C compressor bracket
3967423 Rear P/S bracket
3967420 Front P/S bracket
3976059 AO W/P pulley
3937787 AC Crank pulley
1970 RS/SS 396
32,100 Original Miles