Cast Intake 3866922 any info pls

[opelitis1]

Morning gentlemen!  Came across a 3966922 sbc cast iron intake and need some (any) info on this unit..  Also what is the proper carb. for this non-spreadbore intake....  Date on it is A9 5 meaning Jan 9th 1965???   Thanks!  T.

[JohnZ]

3866922 is an iron intake used on '62-'65 283 and 327 in full-size, Chevy II and Chevelle; it accepts the old Carter WCFB or the old Rochester 4-Jet.

[opelitis1]

Believe I have the Rochester 4-Jet and in which case, where the heck is an identification number on the unit...  I don't have a metal tag that must've accompanied the carb prior to my owning it...  Were these in fact good carbs, (4Jets and or  Carter WCFBs)
What kinda HP figures did these 283/327 engines with the above carb/intake setups put out wayyy back then???  Thanks!!  T.

[JohnZ]

Generally, the base 4-barrel 283's and 327's were 230 and 250hp. The Carter WCFB's were 390CFM, and were used on all '55-'65 Corvette base engines, and on many passenger car applications. Don't know much about the "4-Jet" - it was the predecessor to the Q-Jet, and wasn't in production very long.

[CNorton]

Over the years of NHRA Stock and Super Stock racing I've encountered both the WCFB and the 4-Jet carburetors on a variety of cars.  The WCFB came in a variety of sizes depending on the application.  The smaller ones off the Corvette dual quad motors between 1956 and 1961 were only good when used as a pair.   I've seen the larger ones that came on the 1963 and 1964 Corvette, 250 horsepower, 327 engines support Super/Stock combinations in the range of 550 horsepower.  4-Jet's were available in a variety of applications including some rather larger sizes, especially on late 50's Caddys.  Generally, the 4-Jet, when set up correctly, is capable of supporting an extraordinary level of performance but they usually require an enhanced manifold to fully realize their potential.  I've seen back-to-back tests of a '66 283 that picked up 3 tenths of a second when the stock manifold was swapped with one from a 300 HP, 327 with only jetting changes.

c

[opelitis1]

Thanks JohnZ and CNorton!!  Believe I have a Rochester 4 Jet, 4 distinct tubes coming out of air horn at 45 degree angles..  Is there a code on the unit to help de-cipher exactly what it is??  There is no metal tag associated with the carb, maybe after a cleaning the lad did not re-apply it..   Gonna look up the parts numbers for the 300hp 327ci iron intake and keep my eyes open for one to show itself..  Will try 'n get more info ex the seller and if okay I'll post it???  Possible it came from a SS racer up here???
Ted

[CNorton]

The four brass tubes are indicative of a 4-Jet.  As I recall, that carburetor had a stamped tag affixed to one of the float bowl screws.  The tags were very flimsy and to find one in primo condition would be a long shot.  Be careful using that carburetor on a 327, 300 horsepower manifold.  The 300 horse version came with an AFB and the base won't seal unless you use an adaptor or a combination of base gaskets for both manifolds.  There will be a huge vacuum leak unless you take that into consideration.  I've seen it done with gaskets but an adaptor is a cleaner installation.  Remember that I mentioned NHRA Stock Eliminator?  The whole 4-Jet-on-a-300 horsepower-manifold application is a huge anomaly in the rule book that led to the mix/match situation.  That's a story for a different forum and another day.

c

[JohnZ]

Yup, sounds like a 4-Jet; photo below is a typical Carter WCFB.