74 l82
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Intermediate
Joined: Jan 2012
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74 l82
I just tore down my 74 L82 for a rebuild, my vin is for a L82.My engine builder says everything looks all orignal I have correct matching numbers on block pad. The heads are 333882 and date code work, they have the 1.64 and 2.02 valves but no screw in studs and no guide plates. Has anyone seen this before ?
Race Director
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Drifting
Joined: Apr 2008
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From: Lewisburg WV
thegazman
Chevy made a 333881 head 1974-75 with screw in studs and valve guides with 2.02/1.60 valves. Wouldn't this be the heads they put on an L-82.
Last edited by thegazman; Jan 27, 2012 at 12:35 PM. Reason: correct date
Instructor
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From: colonia New jeresy
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Melting Slicks
Joined: Jul 2009
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Al Colvin's CbtN identifies that some 74 L82 882 castings were built/machined as the early 881's , with the 2.02 valve and screw in studs/guides. I have bone stock 74 Z 14Kmiles, very late production car, 882 heads cast late june, with 2.02 valves and w/Hi speed valve train these also still had the good heavy castings the machine shop told me, I had them overhauled last year.. ,. Matter fact from my observations the 882 /big valves and high speed valve train show up most of the time on cars built after the first of the year more time than not. I keep a eye on the Z28 engines for 74. Generally I see 881 show up in 1974 cars built in the fall of 1973
I would say you heads are L48 that have been been reworked, never seen a HI PER set ( out of an original 73-74 L-82/Z28) of cast 882 HEADS without the high speed valve train. I believe as AL Covin points out , they went to 882 castings for both applications of L-48/L-82 for the better part of 1974 , no reason to cast more 881's as a seperate item with tons of 882 blanks on the shelf already.
I recently found a set of DEC 74 cast 882's with all the goodies .
I would say you heads are L48 that have been been reworked, never seen a HI PER set ( out of an original 73-74 L-82/Z28) of cast 882 HEADS without the high speed valve train. I believe as AL Covin points out , they went to 882 castings for both applications of L-48/L-82 for the better part of 1974 , no reason to cast more 881's as a seperate item with tons of 882 blanks on the shelf already.
I recently found a set of DEC 74 cast 882's with all the goodies .
Last edited by LS4 PILOT; Feb 1, 2012 at 09:37 AM.
Le Mans Master
Joined: Dec 2003
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From: Fremont CA
Original heads would have guide plates and screw in studs. Your heads could be reworked or if your not too particular about originality, pitched in favor of heads that will net you 30-50HP increase. The late open chamber heads flow well but don't have great combustion chambers. Even a set of Vortecs would give you a decent boost in HP.
Advanced
Joined: Sep 2008
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From: Marion Iowa
My 74 L82 was built in December 73. Now I am curious what version of heads are on the motor as my car is very original.
Where is the 6 digit number stamped on the heads? Can it be seen with the heads mounted on the engine?
Thanks
Dave
Where is the 6 digit number stamped on the heads? Can it be seen with the heads mounted on the engine?
Thanks
Dave
Melting Slicks
Joined: Jul 2009
Posts: 2,091
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The casting number and its casting date are found on top the head under the valve cover , you can't miss em. They were cast into the head ( raised digits , not stamped)
Last edited by LS4 PILOT; Feb 1, 2012 at 09:39 AM.
