Two Notch Blocks

chuckl

Well Known Member
Cecil, Would I be correct to say that all 348 truck blocks and all 348 passenger car blocks have a single combustion chamber notch? Also, what engines have a double notch? Truck only? What year(s)? Was it to reduce compression? Valve relief? Lot of bad info out there. Thanks--Chuck
 

oldskydog

Well Known Member
Supporting Member 10
Truck blocks were double notched until they came out with the 333 heads with the combustion chambers. That was in 62. Once the 333 heads were in use, the blocks only needed one notch since the rest of the combustion chamber was in the head.
58-61 truck -double notch
62-65 truck-single notch
 

Phil Reed

Well Seasoned Member
Supporting Member 10
I told you Chuck!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

Chuck asked me about this yesterday and I told him.................get ready for this..................CECIL would know!!!!!!!!!!!!!!!:clap:clap:dance:dance
 

rstreet

Well Known Member
Supporting Member 17
Cecil:
If you do a book please include your irrigation system design and the filing system for your barn
robert
 

chuckl

Well Known Member
Truck blocks were double notched until they came out with the 333 heads with the combustion chambers. That was in 62. Once the 333 heads were in use, the blocks only needed one notch since the rest of the combustion chamber was in the head.
58-61 truck -double notch
62-65 truck-single notch

Thanks Cecil. Inquiring minds need to know.:bang Using the same crank, pistons and heads, would the compression ratio of a double notch block be the same as a single notch block combined with a combustion chamber in the head. In other words, is the chamber volume in the head (333) the same as the volume of one of the notches? In 62, by going to the 333 head, did the CR remain the same?
 

Don Jacks

Well Seasoned Member
Supporting Member 3
Chuck,the compression stayed the same at 7.75 to 1,that much we know,what we will need to know is did the piston stay the same.If so,then it might be safe to assume that the extra notch would account for the same as the combustion chamber in the 333 head.I have heard that the double notch block has rather poor combustion charistics for a performance application.
 

oldskydog

Well Known Member
Supporting Member 10
Chuck,the compression stayed the same at 7.75 to 1,that much we know,what we will need to know is did the piston stay the same.If so,then it might be safe to assume that the extra notch would account for the same as the combustion chamber in the 333 head.I have heard that the double notch block has rather poor combustion charistics for a performance application.
:thinkThanks, Don, you saved me the embarrasment

of having to say "I don't have a f***** clue"
 
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