1969 - L/68 & L/71 correct pulleys

[Steve Antonucci]

Here are a couple of questions for the "numbers guys" here.

What are the correct pulley part numbers for both L/68 & L/71 equipped
Vette's in 1969? Also, what can I expect to spend to get original sets
of each? Are there any particular pulleys that qualify for the
"Holy Grail" award if you find them? Are repro's available? Are they
correct for judging purposes? Lastly, will I be resolved to Ebay to
find these pulleys? Thanks for any & all input.
Steve

[Joe L.]

Re: 1969 - L/68 & L/71 correct pulleys

Steve-----

You left out some important information as far as pullies are concerned. Factors like whether or not the car has A/C (L-68 only) and/or power steering affect this situation. In any event, there is some information which applies regardless in the case of big blocks.

The crank pulley is a 2 groove pulley of either stamped steel or cast iron construction. The stamped steel pulley was likely used for earlier L-71's. It was GM #3921923 and it's still available from GM. The cast iron pulley was likely used for later L-71s and it's GM #3863108. It's also still available from GM. I think that most L-68's used the latter cast pulley, but it's possible that some used the 3921923.

The water pump pulley for both L-68 and L-71 applications was GM #3889372. This pulley was discontinued from SERVICE in June, 1971 and replaced by GM #3995644. That pulley was also discontinued several years ago. The 3889372 is available in reproduction. Both pullies are 3 groove pullies.

The AIR pump pulley for both engine applications was GM #3925522. This pulley was discontinued years ago and is difficult to locate. It is available in reproduction, I believe.

The power steering pump pulley, if so-equipped, for both engine applications is GM #3878245. This is a cast pulley with 2 grooves. It's still available from GM and/or available in reproduction.

The alternator pulley depends on p/s

L-71 engine with p/s------GM #3829193

L-68 engine with p/s------GM #3883978

L-71 engine w/o p/s------GM #3844100

L-68 engine w/o p/s-------GM #3846180

All of the above pullies are GM discontinued, but are available in reproduction.

[Steve Antonucci]

Re: 1969 - L/68 & L/71 correct pulleys

Thanks Joe !

As always, a fountain of knowledge !! A few more items to cover.

1) You noted that the L/68 & L/71 used the same water pump pulley.
That seems strange. Didn't the L/71 - 427 use deep groove pulleys
like the rest of the Chevy line ( L/78 & L/72 ) w/soild lifters?
My research shows that all rectangular port engines ( 1969 ) used
the same cam ( less the L/88 & ZL/1 ). Do you agree?
2) Will I loose points for repro pulleys if judged?
3) What is the best venue to get original pulleys? Ebay? Corvette shows?
As always, many thanks.
Steve

[Joe L.]

Re: 1969 - L/68 & L/71 correct pulleys

Steve-----

1) The 3 groove pulley that I described is the only one ever used on a 1969 L-36, L-68, or L-71. However, earlier 1968 versions of these engines as well as 68-69 L-88/ZL-1 used a different set-up. These engines used 2 pullies sandwiched togther. The outer, single groove, AIR-drive pulley was a GM #3883235. The inner 2 groove pulley was GM #3848904. These pullies were also used on many small blocks and are the ones that some folks refer to as "deep groove".

2) Yes, all rectangular port 1969 big block engines, except L-88/ZL-1, used the same cam. The question is whether it was the GM #3863143 or the GM #3904362. I believe that the only difference between these 2 cams is the presence or absence of the rear journal groove, although some list different specs for the 2 cams. I believe that the 3904362 was used in PRODUCTION for all 1969 rectangular port big blocks, except those noted above;

3) IF the judge detects a repro pulley, then my guess would be that you'd lose points;

4) Both eBay and swap meets, Corvette-oriented and otherwise, are places to find original pullies.