What is my compression with L2316 pistons

[nm9stheham]

1.840 is direct from the FME catalog.

SRP pistons can be any height they wish to make them, I suppose.

 

[ir3333]

to answer your question, with stock 72 cc heads 9.6 :1

 

[Wyrmrider]

is that 72 cc measured or out of some book
did you say whose head?

nm maybe that way to get 0 instead of positive deck for closed chamber heads

 

[70aarcuda]

I have no idea...that is what there specs say....I only copied what they posted.

SRP can make pistons to whatever CH they want to....

NHRA was probably provided with specs from Mopar or someone who had a lot of pistons with 1.815 compression height....

 

[Cudafever]

Also remember that the wrist pin height will go up or down slightly, Depending on the Bore Side. Bore get bigger Pop up gets less to keep the Same Compression ratio.

there not changing it .040 tho...........maybe a typo

 

[ir3333]

Stock X or J's were usually 72 - 73.

 

[nm9stheham]

That is a good typical cc number for them

 

[ir3333]

a lot of guys think they are 68 cc and early 340's were 10.5:1 but i've never seen one.
If you cut those heads to 65 or 68 cc ( i can't remember) then you would be at the factory 10.5:1 rating and be NRA legal.

 

[Wyrmrider]

cc the heads first
I cc each end and then cut to the smallest chamber get them flat before chamber work and equalizing the chambers

 

[nm9stheham]

a lot of guys think they are 68 cc and early 340's were 10.5:1 but i've never seen one.
If you cut those heads to 65 or 68 cc ( i can't remember) then you would be at the factory 10.5:1 rating and be NRA legal.

I am pretty sure it is the 65 cc for NHRA and 10.5. I've worked out the numbers before.... lessee....yep... 66 cc does it with 5 cc eyebrows and 1 cc in the crevice area.

 

[Wyrmrider]

cuda fever must be thinking of stock replacement "compensated" pistons where they reduce the deck with increasing bore
The aftermarket performance industry is all over the place so you have to check

 

[70aarcuda]

nhra spec is 63.3 cc on the heads...

 

[yellow rose]

I am pretty sure it is the 65 cc for NHRA and 10.5. I've worked out the numbers before.... lessee....yep... 66 cc does it with 5 cc eyebrows and 1 cc in the crevice area.

And you can be almost 11:1 in an F or G stocker, which is a 73 340 car and I forget what else fits in that class. And the spec is for the piston as much as .054 out of the deck to get it.

 

[MerlinsMopar]

Iron heads cut to 62cc will put you at 10.2 comp with 0 deck.