Images for a 455 Pontiac GTO heads

November 03, 1975 is the casing date of the Pontiac cylinder heads Rich shown.
Early production 1976 model year cylinder heads.
They look like 101 cc 6X cylinder heads from the combustion chamber side. 350- 400 ci heads.
I own a set of 6H 1976 455 heads. kinda of boat anchor heads for race use....engine only had 200 HP that year, high point of slow smog 70's era, but last year for a Pontiac 455.
Keep them for a restoration project or if someone is restoring a 1976 455 TA & needs them.

Most important....the Center 2 exhaust port photo shots not shown.....Be casted in large digits....6X or 6H
Get them....
Value ? no valves. $50 to 100 each is what I would pay.
Will they make 600 Hp on a 428, NO. lots of porting work to be done. Only an expert can do correct & cost you $2,000 - 3,000.
Was done in the past with low Po Poncho heads, few will do it these days with aftermarket aluminum heads available but they cost $$$$, $3,000 to $10,000 for a pair. Depends how much HP you want. 500 HP or 1,500 HP without ( normally aspirated) a blower or Twin Turbos added. Possible to build up to 4,000 HP from a Pontiac v8 in theory these days. Just need over $100 k to do it... :mrgreen:
 
6H heads have 124-128 cc chambers I recall Rich.
I CC'd my 6H heads in the past. I had to refill the 100 cc Burette. Then continue CC'ing.
455 engine in 1976 had just 7.6 :1 compression that year.
 
Looking at the photos Rich again this morning,
Someone has taken the Smog era Pontiac heads & cut them for .530" P.C. Style Valve stem seals.
Pontiac engines all used s small O-ring style valvestem seal in the special stamped steel retainers used dtock. Along with Stamped steel umbrella splash shields between the spring & retainer.
Quick way to ID Low Po heads at a glance in a pile of junkyard heads.

Just the 1959-62 SD389,
1961-63 SD 421,
Ram Air 2 Ram Air 3 & RAM AIR 4, & RAM AIR 5,
& 1973-74 SD 455
HAD THE P.C. Perfect Circle design valvestem seals factory inatalled.
High Rev Applucation 6K rpm & over.
Pefect Circle invented the 1st positive valvestem seal.
Pre Teflon & Viton seal era.
 
The 421HO, 428HO, 455HO, 400HO & 350HO & 428 Police car had PC Seals too.
 
Brian, There is a lot of Pontiac parts in my area. I share a membership in the Salvage Network and that opens up all the inventories of the salvage yards. Included are about 10K private guys and pickers supplying to eBay vendors. The problem is these private guys will look you in the eyes and lie. If you are 95% sure what they have is not right, these guys will use that 5% to their advantage and convince you other-wise. I really need some sort of Pontiac Book like the Corvette books for casting/parts numbers.
 
chromebumpers said:
Brian, There is a lot of Pontiac parts in my area. I share a membership in the Salvage Network and that opens up all the inventories of the salvage yards. Included are about 10K private guys and pickers supplying to eBay vendors. The problem is these private guys will look you in the eyes and lie. If you are 95% sure what they have is not right, these guys will use that 5% to their advantage and convince you other-wise. I really need some sort of Pontiac Book like the Corvette books for casting/parts numbers.
Click to expand...
I know Pontiacs like Grumpy knows a Big Block Chevy inside out & C3 & C4 Corvettes.
I grew up around Chevy guys. All told me Pontiacs were Shitboxes & never going to be worth squat.
I got the last laugh.
Blew thier dooes off street racing too.
Just bring me with you. I love adventures.
Going to Kentucky for Glens 85 Corvette driveability issue was fun.
Short time together we talked a lot.
I know how to play Poker & Win Richard.
 
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