Topic: 69 427 L71Cylinder Head Casting Lettering
in Forum: C3 Engines
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Hello,

I removed the valve cover from the left cylinder head and saw this cast into the head,
"HI-PERF"
Does this casting correspond to the correct head for a L71 435 HP engine?
Thanks for any replies!,
Mike
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SHELBYVILLE, TN - USA
Joined: 7/5/2002
Posts: 3942
Vette(s): 1976 L48 auto
1978 L82 4speed
1994 LT1 6speed
1978 L82 4speed
1994 LT1 6speed
just doing a quick online search,
|UPDATED|1/28/2017 1:36:41 PM (AZT)|/UPDATED|
cast# year port chamber engines
14081052...85-87...oval...OPEN...366T, 427T, 454 Truck, Marked "HiPerf"
14092359...86-90...oval...OPEN...366T, 427T, Marked "HiPerf"
14092359...86-90...oval...OPEN...366T, 427T, Marked "HiPerf"
check your casting numbers, if you can post them on here, or you can look them up to establish when yours were made. I got this info from
http://garage.grumpysperformance.com/index.php?threads/closed-vs-open-chamber-big-block-heads-and-casting-s.3960/
the two i pasted there was about 2/3 down the page just above the pictures of the dome piston...
hope that helps :)
|UPDATED|1/28/2017 1:36:41 PM (AZT)|/UPDATED|

Moderator
Duncanville, TX - USA
Joined: 11/8/2003
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Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
Need the casting number AND date....."Hi Perf" is irrelevant.
Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Thanks for replies!
I will look at the head again to gather the needed information.
I had an unexpected repair on the wife's Subaru yesterday afternoon that delayed any further posting. rear brakes and rotors shot, replaced in our heated garage, cozy warm!
Mike
According to my black book the casting number you are looking for is 3919840 for a '69 435hp cast iron head. The casting date should be anytime before the engine build date stamped into the pad up to six months prior. Not a BB expert, but it looks like the casting number in your pic is behind the third rocker from the rh side (#5 intake). The casting date looks like it's just to the left of the #1 intake rocker. Take a peek and let us know what you see. Nice car !!
John Sigmund

valkman57@sbcglobal.net
NCRS Member 61302
NW NCRS Chapter Member

Duct tape is the new Black !!
Head Casting Number, 3964291
According to this site I am legit!!
http://www.nastyz28.com/bbcmenu.php

|UPDATED|1/29/2017 2:56:13 PM (AZT)|/UPDATED|

Moderator
Duncanville, TX - USA
Joined: 11/8/2003
Posts: 20214
Vette(s): #1-1974 L-48 4spd Cp Med Red Metallic/Black deluxe int w/AC/tilt/tele./p/w-p/b/
Am-Fm/map light National/Regional/Chapter NCRS "Top Flight"
#2-1985 Bright Red/Carmine Cp.L-98/auto
Member: NCRS, NCRS Texas, Corvette Legends of Texas
Can't make out the first letter, but if it is an "E", it is May 3, 1968....if it is "F", it is June 3, 1968. As long as the date is BEFORE engine build date, yer golden.


Joel Adams
C3VR Lifetime Member #56
My Link
(click for Texas-sized view!) NCRS
"Money can't buy happiness -- but somehow it's more comforting to cry in a CORVETTE than in a Kia"
Hey Mike - just doubled checked 3 different sources and they all point towards the 3919840 number I originally posted for a '69 L71. I also see your reference to the NastyZ28 site. Not sure why the descrepency, but welcome to the world of Corvette "matching numbers". I also found reference to your casting number 3964291 on another website that you might want to check out, www.minuit10.net. They show that casting as '69/'70 427 but do not list it as an L71 435hp application. Same rectangular port, big valves as the 840 casting but the size of the combustion chamber is slightly different. Yours might still be correct, like I said I'm certainly not a BB guy, definately worth more research. The casting date you posted is either E or F 3 8, which equates to a May or June 3rd, 1968. Those dates would be correct for a relatively early (Aug thru Dec '68 engine/car build date of a '69 car. Since the head casting numbers are just one piece of the puzzle, have you ever researched your block casting and engine stamp pad info ?? They should give you further clues as to your L71.
John Sigmund

valkman57@sbcglobal.net
NCRS Member 61302
NW NCRS Chapter Member

Duct tape is the new Black !!
in Forum: C3 Engines
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