Small Block Cylinder Heads 'Stock Specs'
Small Block Cylinder Heads
CC's / Port Volume / Size / Flow
1966 - 1967 {273} Casting #2658920
Heart-Shaped Combustion Chamber
Factory CC Level..........................62.0 to 65.5 CC's
Recommended Minimum CC's......57.3 CC's
Intake Port Gasket Size...............1.05" x 2.07"
Exhaust Port Gasket Size.............1.14" x 1.59"
Intake Valve................................1.78"
Exhaust Valve..............................1.50"
Intake Bowl Size.........................1.53" {86% of Valve}
Intake Port.................................125 CC
Exhaust Port...............................61 CC
Intake Flow...............................160 CFM @ .450" Lift
Exhaust Flow.............................107 CFM @ .450" Lift
Intake-to-Exhaust Flow.............64.8%
Small Block Cylinder Heads
CC's / Port Volume / Size / Flow
1968 - 1971 {340} Casting #2531984 'X-Heads'
Open-Shaped Combustion Chamber
Factory CC Level..........................65.0 to 69.0 CC's
Recommended Minimum CC's......63.5 CC's
Intake Gasket Port Size..............1.16" x 2.27"
Exhaust Gasket Port Size............1.25" x 1.75"
Intake Valve..............................2.02"
Exhaust Valve............................1.60"
Intake Bowl Size........................1.75" {87% of Valve}
Intake Port Size........................160 CC
Exhaust Port Size.......................70 CC
Intake Flow.............................215 CFM @ .450" Lift........221 CFM @ .500" Lift
Exhaust Flow...........................140 CFM @ .450" Lift........142 CFM @ .500" Lift
Intake-to-Exhaust Flow....................65.5%..............................64.1%.............
Small Block Cylinder Heads
CC's / Port Volume / Size / Flow
1970 {340 T/A} Casting #3418915 'J-Head'
Open-Shaped Combustion Chamber
Factory CC Level...........................68.0 to 73.0 CC's
Recommended Minimum CC's.......63.5 CC's
Intake Gasket Size.......................1.16" x 2.27"
Exhaust Gasket Size.....................1.25" x 1.75"
Intake Valve................................2.02"
Exhaust Valve..............................1.60"
Intake Bowl Size..........................1.75" {87%}
Intake Port Size...........................157 CC
Exhaust Port Size..........................73 CC
Intake Flow.................................213 CFM @ .450".........220 CFM @ .500" Lift
Exhaust Flow...............................146 CFM @ .450".........148 CFM @ .500" Lift
Intake-to-Exhaust Flow.......................68.8%............................67.3%..........
Small Block Cylinder Heads
CC's /Port Volume / Size / Flow
1968 - 1974 {273 & 318} Casting #2843675
Open-Shaped Combustion Chamber
Factory CC Level.........................67.0 - 68.5 CC's
Recommended Minimum CC's.....60.6 CC's
Intake Gasket Size....................1.05" x 2.07"
Exhaust Gasket Size..................1.14" x 1.59"
Intake Valve..............................1.78"
Exhaust Valve............................1.50"
Intake Bowl Size.......................1.53" {86%}
Intake Port Size........................127 CC
Exhaust Port Size........................61 CC
Intake Flow...............................160 CFM @ .450" Lift...........162 CFM @ .500" Lift
Exhaust Flow.............................107 CFM @ .450" Lift...........109 CFM @ .500" Lift
Intake-to-Exhaust Flow......................66.8%...................................67.1%..........
Mope-Kid D-3
Results coming u,,,,,,,,,,,
Casting #530006671
1992 - 2004 {318 Magnum} Casting #53006671 {Also Casting #'s 671/466/714}
CC's / Port Volume / Size / Flow
Closed-Chamber Combustion Chamber
Weight......................................62 lbs.
Factory CC Level.......................60.0 to 66.0 CC's
Recommended CC Level............60.0 CC's
Intake Port Gasket Size.............1.18" x 2.18" (Actual Port Size = 1.08" x 2.075"}
Exhaust Port Gasket Size...........1.08" x 1.80"
Intake Valve..............................1.920"
Exhaust Valve............................1.625"
Intake Bowl Size.......................1.65" {86%}
Intake Port Volume...................153 CC
Exhaust Port Volume...................64 CC
Intake Flow..............................193 CFM @ .450" Lift........199 CFM @ .500" Lift
Exhaust Flow............................147 CFM @ .450" Lift........149 CFM @ .500" Lift
Intake-to-Exhaust Flow......................76.5%..............................75%..............
(Trouble posting pics, will try again)
I have a very early, first year 340 bare block with caps. Spring of 2021 I had it fully checked out, had one cylinder sleeved on the original bore, machined .030 over, align bored, etc, etc Have the receipt from Domhoff’s in Harmony, PA. Cast in June of 1967, this has to be one of the very first 340 blocks to come out of the Foundry. I found the #’s at the deck surface just beneath the left head, but the #’s at the back of the block (vin?) isn’t real legible and there are no #’s at the pan rail. A super-find for someone doing a period correct ‘68 Dart or Barracuda resto. I do not have a crankshaft but a friend has one that may be willing to part with for a reasonable price. I’m asking $2500 for the block and will be more flexible if you’re interested in the heads...
Also have a pair of bare X heads. These were checked out, but no machine work done. No valves or springs, but I do have rocker shafts and adjustable rocker arms and maybe a set of cup pushrods. Asking $700 for the heads....available only if I sell the block.
I don’t want to ship, but may consider delivery to Chry/Carlisle
I’m just north of Pittsburgh. Just off Interstate 79 and PA Turnpike. 30 min from I-80.
Thanks FABO!
Finally-pics…sorry !
Small Block Cylinder Heads
CC's / Port Volume / Size / Flow
1966 - 1967 {273} Casting #2658920
Heart-Shaped Combustion Chamber
Factory CC Level..........................62.0 to 65.5 CC's
Recommended Minimum CC's......57.3 CC's
Intake Port Gasket Size...............1.05" x 2.07"
Exhaust Port Gasket Size.............1.14" x 1.59"
Intake Valve................................1.78"
Exhaust Valve..............................1.50"
Intake Bowl Size.........................1.53" {86% of Valve}
Intake Port.................................125 CC
Exhaust Port...............................61 CC
Intake Flow...............................160 CFM @ .450" Lift
Exhaust Flow.............................107 CFM @ .450" Lift
Intake-to-Exhaust Flow.............64.8%
Small Block Cylinder Heads
CC's / Port Volume / Size / Flow
1968 - 1971 {340} Casting #2531984 'X-Heads'
Open-Shaped Combustion Chamber
Factory CC Level..........................65.0 to 69.0 CC's
Recommended Minimum CC's......63.5 CC's
Intake Gasket Port Size..............1.16" x 2.27"
Exhaust Gasket Port Size............1.25" x 1.75"
Intake Valve..............................2.02"
Exhaust Valve............................1.60"
Intake Bowl Size........................1.75" {87% of Valve}
Intake Port Size........................160 CC
Exhaust Port Size.......................70 CC
Intake Flow.............................215 CFM @ .450" Lift........221 CFM @ .500" Lift
Exhaust Flow...........................140 CFM @ .450" Lift........142 CFM @ .500" Lift
Intake-to-Exhaust Flow....................65.5%..............................64.1%.............
Small Block Cylinder Heads
CC's / Port Volume / Size / Flow
1970 {340 T/A} Casting #3418915 'J-Head'
Open-Shaped Combustion Chamber
Factory CC Level...........................68.0 to 73.0 CC's
Recommended Minimum CC's.......63.5 CC's
Intake Gasket Size.......................1.16" x 2.27"
Exhaust Gasket Size.....................1.25" x 1.75"
Intake Valve................................2.02"
Exhaust Valve..............................1.60"
Intake Bowl Size..........................1.75" {87%}
Intake Port Size...........................157 CC
Exhaust Port Size..........................73 CC
Intake Flow.................................213 CFM @ .450".........220 CFM @ .500" Lift
Exhaust Flow...............................146 CFM @ .450".........148 CFM @ .500" Lift
Intake-to-Exhaust Flow.......................68.8%............................67.3%..........
Small Block Cylinder Heads
CC's /Port Volume / Size / Flow
1968 - 1974 {273 & 318} Casting #2843675
Open-Shaped Combustion Chamber
Factory CC Level.........................67.0 - 68.5 CC's
Recommended Minimum CC's.....60.6 CC's
Intake Gasket Size....................1.05" x 2.07"
Exhaust Gasket Size..................1.14" x 1.59"
Intake Valve..............................1.78"
Exhaust Valve............................1.50"
Intake Bowl Size.......................1.53" {86%}
Intake Port Size........................127 CC
Exhaust Port Size........................61 CC
Intake Flow...............................160 CFM @ .450" Lift...........162 CFM @ .500" Lift
Exhaust Flow.............................107 CFM @ .450" Lift...........109 CFM @ .500" Lift
Intake-to-Exhaust Flow......................66.8%...................................67.1%..........
Mope-Kid D-3
Results coming u,,,,,,,,,,,
Casting #530006671
1992 - 2004 {318 Magnum} Casting #53006671 {Also Casting #'s 671/466/714}
CC's / Port Volume / Size / Flow
Closed-Chamber Combustion Chamber
Weight......................................62 lbs.
Factory CC Level.......................60.0 to 66.0 CC's
Recommended CC Level............60.0 CC's
Intake Port Gasket Size.............1.18" x 2.18" (Actual Port Size = 1.08" x 2.075"}
Exhaust Port Gasket Size...........1.08" x 1.80"
Intake Valve..............................1.920"
Exhaust Valve............................1.625"
Intake Bowl Size.......................1.65" {86%}
Intake Port Volume...................153 CC
Exhaust Port Volume...................64 CC
Intake Flow..............................193 CFM @ .450" Lift........199 CFM @ .500" Lift
Exhaust Flow............................147 CFM @ .450" Lift........149 CFM @ .500" Lift
Intake-to-Exhaust Flow......................76.5%..............................75%..............
(Trouble posting pics, will try again)
I have a very early, first year 340 bare block with caps. Spring of 2021 I had it fully checked out, had one cylinder sleeved on the original bore, machined .030 over, align bored, etc, etc Have the receipt from Domhoff’s in Harmony, PA. Cast in June of 1967, this has to be one of the very first 340 blocks to come out of the Foundry. I found the #’s at the deck surface just beneath the left head, but the #’s at the back of the block (vin?) isn’t real legible and there are no #’s at the pan rail. A super-find for someone doing a period correct ‘68 Dart or Barracuda resto. I do not have a crankshaft but a friend has one that may be willing to part with for a reasonable price. I’m asking $2500 for the block and will be more flexible if you’re interested in the heads...
Also have a pair of bare X heads. These were checked out, but no machine work done. No valves or springs, but I do have rocker shafts and adjustable rocker arms and maybe a set of cup pushrods. Asking $700 for the heads....available only if I sell the block.
I don’t want to ship, but may consider delivery to Chry/Carlisle
I’m just north of Pittsburgh. Just off Interstate 79 and PA Turnpike. 30 min from I-80.
Thanks FABO!
Finally-pics…sorry !
