Big Block 4 bolt valve covers

[Longknife]

I recently purchased a car with a 76 440 truck engine. I just discovered that the valve covers were the early 4 bolt type. Although he said stated "The heads have been milled .030, port matched and had the bowls blended, and had a valve job" he never stated he replaced the heads. Where these only used in the early '60s? would they all have the same casting #? THNX. LK

 

[pnora]

I recently purchased a car with a 76 440 truck engine. I just discovered that the valve covers were the early 4 bolt type. Although he said stated "The heads have been milled .030, port matched and had the bowls blended, and had a valve job" he never stated he replaced the heads. Where these only used in the early '60s? would they all have the same casting #? THNX. LK

Pull a cover and get the casting number. 4 bolt valve covers will still bolt on a 6 bolt head. Getting the casting number will tell the story.

 

[Lefty71]

There were various casting numbers for the heads back then too.... 4 bolt for passenger cars ended in '63 and they went to the 6 bolts ones until production ended in '78 or so. Hard to know for sure why, but I'd bet someone wanted to bump up the compression since all those old heads were closed chambers. I'd pull the covers and post up the casting number.....maybe you just scored some max wedge heads??!!

 

[Builderguy]

No proof of this, but my understanding is that B/RB motors changed from 4 bolt to 6 bolt pattern valve covers in '65. Others probably know more on this than I.

 

[pnora]

No proof of this, but my understanding is that B/RB motors changed from 4 bolt to 6 bolt pattern valve covers in '65. Others probably know more on this than I.

Point is the poster could have 6 bolt heads under the 4 bolt covers. That's why he needs to pull one and get a casting number. Otherwise its just a guessing game.

 

[33 IMP]

I think Lefty71 nailed it.
If they are 4bolt heads when you pull the covers, you'll find 63 or earlier heads, with aluminum rocker stands, and heads with closed chambers, most likely used to bump the compression up from the 7.5 to 1 a late 440 really is.
Port flow won't be as good as later heads, and unless they were changed, they'll have smaller valves.
They won't be maxwedge heads. If they were, you'd KNOW!

 

[Big Bad Dad]

No proof of this, but my understanding is that B/RB motors changed from 4 bolt to 6 bolt pattern valve covers in '65. Others probably know more on this than I.

My 64 Plymouth has 6 bolt valve covers.

 

[turbine68rt]

RB Valve Covers

 

[turbine68rt]

4 bolt VC heads are 1958-1963. Dozens of casting numbers, they even made these with 1.95 intake valves. Wanna see a photo, I have a pair.

In the '63 model year there were both. Here's a pic I posted in another thread of a '63 with pedestal rockers and 6 bolt heads.

 

[Lefty71]

RB Valve Covers

Very cool info.... link saved!!

 

[Builderguy]

Yea Hah, I am now a member of the RED "X" club on a topic that I said others probably know more about. Tough crowd!!!! LOL

 

[Lefty71]

Tough crowd!!!! LOL

Msybe hes sayin, for one, he doesnt know more than you??!!
More likely a simple fat fingered mistake??

 

[Longknife]

Thanks For the info!