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cig20 01-30-2013 08:27 PM

bb heads
 
found a leak doing a leakdown test
pulled heads to replace head gaskets
are gm castings 353049 heads with alum lunati rockers any good
thought i would have valve job done while off
anything i should have done at the same time of work being done on heads?

brian becker 01-30-2013 08:40 PM

head
 
049 and 781 are chevys best early oval port heads Mild cleanup under the valves is worth alot for the effort if your looking for more power

brian becker 01-30-2013 08:42 PM

head
 
forgot to add bigger valves help a bunch also

endeavour32 01-30-2013 09:25 PM

Make sure you have the heads pressure checked. I didn't on my last set and found out later the guides were leaking water. So I had to rip the top half of the engine down in the boat because I wanted to save a few buck. Learn from my mistake.

cig20 01-31-2013 08:40 AM

does anyone know the spec of these heads ? or where i can find them

Budman II 01-31-2013 10:10 AM

Here is some info I found on the web a couple years ago. I think it is reasonably accurate. It lists the 049 casting as having 122cc chambers.

Chev Big Block V8 Cylinder Head Casting Numbers
CASTING#.....YEAR...PORT TYPE.....ENGINE SIZE
330864.....68-84...oval...OPEN...396, 402, 366T, 427T, 454 Truck
330865.....68-84...oval...OPEN...396, 402, 366T, 427T, 454 Truck
330866.....68-78...oval...OPEN...366T, 427T
330867.....68-73...oval...OPEN...427T
336765.....68-78...oval...OPEN...427T
336768.....73-76...oval...OPEN...427T
336781.....73-85...oval...OPEN...454, 118cc chamber, 256/114cc ports
343771.....68-86...oval...OPEN...366T, 427T, 454
343772.....68-86...oval...OPEN...366T, 427T, 454
343783.....70-76...oval...OPEN...454 Truck
346236.....75-87...oval...OPEN...454, 120cc chamber, 225/116cc ports
352625.....70-76...oval...OPEN...454 Truck
353049.....73-84...oval...OPEN...454, 122cc chamber, 255/119cc ports
366765.....74-78...oval...OPEN...427T
473328.....68-69...oval...OPEN...366T
3856206....65-66...oval..CLOSED..396, 97cc chamber
3856208....65......rect..CLOSED..396/425hp, 109cc chamber 396/375hp "Z-16" Chevelle
3856213....66-82...oval..CLOSED..366T, 427T
3856260....68......oval..CLOSED..396 Truck
3872702....65-66...oval..CLOSED..396, 427, 98cc chamber
3873858....65-67...rect..CLOSED..396, 427, 109cc chamber
3876875....77-85...oval...OPEN...427T
3904390....67......oval..CLOSED..396, 427, 98cc chamber
3904391....67......rect..CLOSED..396, 427, 107cc chamber
3904392....67......rect..CLOSED..427, Aluminum, L88, L89, 107cc chamber
3904393....68-76...oval...OPEN...366T
3908952....67......oval...OPEN...427, "M.Truck", Marine
3909802....67......oval..CLOSED..396, 427, 101cc chamber
3917215....67-68...oval..CLOSED..396, 427, 101cc chamber
3917219....68-85...oval...OPEN...366T, 427T
3919840....67-69...rect..CLOSED..396, 427, 107cc chamber
3919842....68-69...rect..CLOSED..396, 427, Aluminum L88, L89, 107cc chamber
3931063....68-69...oval..CLOSED..396, 402, 427, 101cc chamber
3933148....69-84...oval...OPEN...'69 396/265hp, 366T, 427T, 112cc chamber
3933149....68-76...oval...OPEN...427T, 122cc chamber
3935401....68-76...oval...OPEN...427T
3946074....69&71...rect...OPEN...'69 427 L88, ZL1, Aluminum, 118cc chamber '71 454 LS6, "round exhaust port"
3964290....69-70...oval..CLOSED..396, 402, 427, 454, 101cc chamber Large or small hex spark plugs used
3964291....69-70...rect..CLOSED..396, 402, 427, 454, 109cc chamber Large or small hex spark plugs used
3965198....68-69...oval..CLOSED..396 Truck
3975950....68-70...oval...OPEN...396, 402 Truck, 366T, 427T
3986133....68-85...oval...OPEN...366T, 427T, 454 Truck
3986135....69-73...oval...OPEN...366T, 427T
3986136....68-84...oval...OPEN...366T, 427T, 454 Truck
3993820....71......oval...OPEN...402, 113cc chamber, 255/114 ports
3993820....71-84...oval...OPEN...454 Passenger and Trucks, 113cc chamber, 255/114 ports
3994026....71......rect...OPEN...454 LS6, 118cc chamber
3999241....72......oval...OPEN...402, 454, 113cc chamber
6272292....70-78...oval...OPEN...402, 454
6272990....70-up...rect...OPEN...454 service replacement, used on some MKIV crate engines, 118cc chamber
10045427...........rect..........Pontiac/Chevy Aluminum, 91cc chamber Large Port, race
10049875...........rect..........Pontiac/Chevy Aluminum Small port, race
10051128...........rect..........Bowtie, Aluminum 72cc chambers Symmetrical ports
10051129...........rect..........Bowtie, Aluminum "raw" casting, Symmetrical ports
10052902...........oval...OPEN...MkIV, 427T
10101140...91-up...oval..CLOSED..Gen.V 366T, 427T
10114156...91-up...oval...OPEN...Gen.V & VI 454, 118cc chamber
10141279...96-up...oval..CLOSED.."Vortec 7400", 100cc chambers
10487052...77-90...oval...OPEN...366T
12363391...96-up...oval...OPEN...Bowtie, Aluminum, Signature Series, fits MKIV, Gen.V, Gen.VI, 110cc chamber
12363401...96-up...rect...OPEN...Bowtie, Aluminum, Signature Series, fits MKIV, Gen.V, Gen.VI, 118cc chamber
12558162...01-up...oval..CLOSED..Gen.VII,"Vortec 8100", 8.1L, 496, truck
12560241...98-up...oval..CLOSED.."Vortec 7400", 100cc chambers
12562932...91-95...oval...OPEN...Gen.V, truck crate motor, 118cc chambers
12562934...00-up...rect...OPEN...Gen.VI 502 Marine 14011077...69-up...rect...OPEN...Aluminum, fits MKIV, "C-port" 118cc chamber, also sold as a "solid" head
14044861...84-96...rect..........Bowtie, Aluminum, MkIV, "raised runners", 1st design, 105cc chamber
14044861...96-up...rect..........Bowtie, Aluminum, Signature Series, fits MKIV, Gen.V, Gen.VI "raised runners", 2nd design, 115cc chamber
14044861...84-96...rect..........Bowtie, Aluminum, MkIV "raw" casting of "861" MKIV 1st design
14081045...78-87...oval...OPEN...454
14081052...85-87...oval...OPEN...366T, 427T, 454 Truck, Marked "HiPerf"
14092359...86-90...oval...OPEN...366T, 427T, Marked "HiPerf"
14092360...86-90...oval...OPEN...454 Truck, "peanut" round ports
14096188...70-71...rect...OPEN...454 service replacement, also used on later Mark IV LS-6, LS-7 and 454 HO crate motors, 116cc chamber
14097088...91-up...rect...OPEN...Gen.V 454/502 HO, 118cc chamber
24502585...97......rect..........Olds/Chevy, DRCE 2, Pro Stock aluminum, for blocks w/4.900" bore spacing
25534404...04......rect..........Olds/Chevy, DRCE 3, Pro Stock, aluminum, for blocks with 4.900" bore spacing
T = Tall deck
Oval includes both "peanut" (also called "round") ports and large oval ports

cig20 01-31-2013 10:18 AM

thanks
with that being said what cam would be in the motor ?

endeavour32 01-31-2013 01:11 PM

Are they the factory heads? I think GM stopped putting the 049/781 on engines in the early 80's. I'm guessing here but I'm pretty sure you have a 330 engine, so its a small cam (213/217 duration). Now if someone swapped the heads your cam could be anything.

cig20 01-31-2013 08:43 PM


Originally Posted by endeavour32 (Post 3859048)
Are they the factory heads? I think GM stopped putting the 049/781 on engines in the early 80's. I'm guessing here but I'm pretty sure you have a 330 engine, so its a small cam (213/217 duration). Now if someone swapped the heads your cam could be anything.

and no way of telling what cam without pulling engine? and thats not happening this year

endeavour32 01-31-2013 10:46 PM

If you can measure your lift, we might be able to give you an idea of what you have. The 454 Mag and 330 engines have different lift. What year are the engines?


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