L36 Head Casting # 8134--Interesting info added...
#1
Senior Member
Posts like a Corvette
Thread Starter
Join Date: Jan 2007
Location: San Diego, CA
Posts: 1,451
Likes: 0
Received 0 Likes
on
0 Posts
L36 Head Casting # 8134--Interesting info added...
Been referencing this thread since ordering up a set of used heads:
http://www.bonnevilleclub.com/forum/...t=head+casting
They come in, and lo and behold they are neither 2261 nor 4781, but are casting # 8134
Anyone know anything about that casting number?
EDIT: I can say that they DO have the injector bosses in the tops like the 4781 heads, but probiing inside the intake port, I find they do NOT have the injector "pocket" of the 4781 heads.
http://www.bonnevilleclub.com/forum/...t=head+casting
They come in, and lo and behold they are neither 2261 nor 4781, but are casting # 8134
Anyone know anything about that casting number?
EDIT: I can say that they DO have the injector bosses in the tops like the 4781 heads, but probiing inside the intake port, I find they do NOT have the injector "pocket" of the 4781 heads.
#5
Senior Member
Posts like a Corvette
Thread Starter
Join Date: Jan 2007
Location: San Diego, CA
Posts: 1,451
Likes: 0
Received 0 Likes
on
0 Posts
I am 99% certain it says 8134. That is backed up by looking at the online product catalog at Rock Auto, which says their OEM replacement head for a 1998 Buick LeSabre Limited is a replacement for casting numbers 2261, 4781, or 8134.
I guess I'm mostly just wondering whether these castings are newer, older, have any known issues, whatever...anyway, they are supposed to be off a 2000 Grand Prix.
I guess I'm mostly just wondering whether these castings are newer, older, have any known issues, whatever...anyway, they are supposed to be off a 2000 Grand Prix.
#6
Senior Member
Posts like a Corvette
Thread Starter
Join Date: Jan 2007
Location: San Diego, CA
Posts: 1,451
Likes: 0
Received 0 Likes
on
0 Posts
Originally Posted by firebuick
are these for porting and to match youre LIM
-Use these heads as a guide to port another LIM more perfectly
-Polish all the runners inside the heads
-Smooth and blend the bowls
-Smooth the chambers (using some spare valves to shield valve seats)
-EVER SO SLIGHTLY port the exhaust ports (but NOT the intake ports)
-Three angle valve job (at a shop)
-Undercut valves 25 degrees (at a shop; if machinist says it'* OK)
-Mill 0.020 inches off deck (at a shop; if funds allow)
-Put on LS6 (or CompCams 105#, if funds allow) springs and CompCams retainers
-Put on 1.85 intake / 1.80 (or 1.60, depending on test results) exhaust modded stock rockers
I've removed the valves and inspected these heads for: warpage in the mating surfaces, play in the valveguides, scoring on the valvestems and inside the guides, condition and runout in valve seats, and for cracking between valves, and they've both passed all the tests. Time to buy some more stuff
#7
Senior Member
Posts like a Corvette
Thread Starter
Join Date: Jan 2007
Location: San Diego, CA
Posts: 1,451
Likes: 0
Received 0 Likes
on
0 Posts
Anyone?
Perhaps I've made an L36 discovery here, if the 8134 casting number--like the earlier style 2261 head but unlike the '98-'99 4781 casting--does not have the injector hole "pocket" in the intake.
Perhaps I've made an L36 discovery here, if the 8134 casting number--like the earlier style 2261 head but unlike the '98-'99 4781 casting--does not have the injector hole "pocket" in the intake.
#9
Senior Member
Posts like a Corvette
Thread Starter
Join Date: Jan 2007
Location: San Diego, CA
Posts: 1,451
Likes: 0
Received 0 Likes
on
0 Posts
Here are the same heads, cleaned and purtied up:
I'm still curious though; does anyone know whether this 8134 casting number corresponds with a certain year range?
I'm still curious though; does anyone know whether this 8134 casting number corresponds with a certain year range?
#10
Senior Member
Posts like a Corvette
Thread Starter
Join Date: Jan 2007
Location: San Diego, CA
Posts: 1,451
Likes: 0
Received 0 Likes
on
0 Posts
Here'* some shots of those 8134 L36 heads, with the intake and exhaust runners and bowls polished up a bit (though not ported):