prepping for ncrs judging - after-market fuel pump needs to be replaced with "original" "AC" - judging manual shows part # 6440568 - apparently no longer available except as remanufactured part - I've seen some part #s 6440658 associated with this engine - help! - what is correct AC part # and anyone know of a source? many thanks!
-
-
Re: 68 327/350hp fuel pump?
Steven----
The AC type 40658 was the fuel pump used for all 1968-69 small block applications. Once-upon-a-time, this pump was available from GM under GM #6417337. However, that pump was discontinued in August, 1971 in favor of the AC type 40709, GM #6470110. This pump is the one actually used in PRODUCTION for most LT-1's. The 40709 is configured considerably different than the 40658, but it will SERVICE the 68-69 small block applications satisfactorily.
Since the 40658 was discontinued so long ago, many folks have come to think of the 40709 as the correct pump for 68-69 small blocks. It's not, though; the 40658 is the correct pump.
Curiously, although the 40658 was discontinued through the GM parts system so long ago, it remained available through the Delco parts system for at least 25 more years. In fact, I purchased a bunch of these things [none for sale]from a Delco dealer at a Corvette show about 10 or 15 years ago for a very low price. They were even the "AC logo" versions.
Both the 40658 and the 40709 are now discontinued through both the GM and Delco parts systems and I don't know where to get any. A 40658-equivalent pump is available from Airtex, though. Of course, it lacks "AC" logo and "numbers", but it's pretty much the same configuration as original.In Appreciation of John Hinckley -
Re: 68 327/350hp fuel pump?
Joe: wow! that's an amazing display of knowledge, and really helps me .. thanks for taking the time to post this info ..Comment
-
Re: 68 327/350hp fuel pump?
Check out Paragon 11534 part #. It has AC logo and part # 40709 on it. $155.Comment
-
Re: 68 327/350hp fuel pump?
In January 1994 I purchased 4 NOS AC fuel pumps for $5 each but none were in AC boxes at the NCRS swap meet in Cypress Gardens. I got them cheap because the seller could not identify them but I could. All had the "AC" casting and all were stamped "DI 40658". I believe the "DI" is a date code where "D" = April and "I" = 1969. I no longer have any of them.
Like Joe has stated, the GM part # is 6417377 and according to Chevrolet Parts History they were discontinued in August 1971. They were used on 1968 Corvettes w/327 and 1969 Corvettes w/350 (base engines).Comment
-
Re: 68 327/350hp fuel pump?
Steven-----
The Airtex part number is 40709. However, from what I can tell, while it uses the same number as the Delco 68-69 replacement pump, it is configured like the 40658. There were 2 basic differences between the 40658 and the 40709. These are:
1) The valve chamber on the 40658 is much shorter than the valve chamber on the 40709. The valve chamber is the cylindrical extension of the base between the base and the inlet nipple;
2) The angular relationship between the inlet nipple and the outlet fitting is different between the 2 fuel pumps. However, the outlet fitting is in the same relative position for both pumps so that the steel fuel line originally used for 68-69 small blocks will fit either pump perfectly.
Pump pressures and capacities between the 2 pumps are similar.
By the way, Airtex was the actual manufacturer of these pumps for Delco and GM after the AC Division ceased the manufacture of all mechanical fuel pumps in the very early 1980's. Just about any mechanical fuel pump that one purchases from GM or Delco today will be of Airtex manufacture.In Appreciation of John HinckleyComment
Comment