454 Big Block Chevy Identification

jfields1357

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Hey everyone! I recently purchased an 84 Monte Carlo ss with a 454bbc swap. Im trying to figure out what gen block it is. The only number ive come across is
CDS 140 187
 

63Half-ton461

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1978 Monte Carlo 383 slammed
What casting number is at the back of the block?
 

63Half-ton461

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1978 Monte Carlo 383 slammed
215's are a closed chamber vette head, 3917215....67-68...oval..CLOSED..396, 427, 101cc chamber ....... 454 is not listed as an application. Any chance your motor could actually be a 427 ?
 

jfields1357

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3462361975-87454Open113cc.

This is the number I found on the heads. I will double check tomorrow just to make sure. From what i've read these heads are the peanut ports which is sort of a bummer.
 

63Half-ton461

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Yeah i was looking at a set a 236's a guy was selling about a month ago, the chamber looks like a 781 casting so im assuming 118cc, i would assume the 236's are a small port version of the 781.
I know Mortec says they are 113cc but i'm pretty sure that's incorrect

If you don't like the 236's look for a set of 148's or 875's they were made into the late 80's and are easier to find.
They are the same as 241 castings and work very well on the 454
I just scored a set of 875's for a 402 that i have and im running a set of big valve 241's on a 454 that im real happy with.
Your 454 is probably a truck motor it would be interesting to see what casting number is at the back of the block, try and maneuver a camera back in there an snap a picture to find out what the number is.
 

63Half-ton461

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hum so its a 14015445...454.......78-90...2 or 4 bolt, what color is it, orange, blue or black has it been repainted, if so what's underneath, orange would be earlier block, def a gen IV block .

Motor should run pretty good with those 215 castings, compression wise i think it would be at 9.5:1 with flat-tops,
 
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