Thread: Piston Identification

Well they are not 8.13:1 pulled the top of a 8.13:1 3.9Ltr and these are less volume so probably 9.35:1 but i`ll measure at some time and also note the deck height for both .

Probably not but .........

Does anyone know the piston volume of a 9.35:1 4.0ltr , i have what a 8.37:1 is ?

I would also like to know the Piston volume of 8.13:1 (or whatever the ratio is ) 4.6Ltr and the 9.35:1 piston volume if anyone happens to know ?

Also the piston deck height of a 4.6Ltr , i have it for a 4.0Ltr 8.37 ?

Also ,also does anyone know of a reason not to use Earlier Exhaust valves from 14 bolt ERC 0216 heads in later 10 bolt HRC 2479 Heads ?

Although the HRC Heads from 4.0/4.6 Engines have smaller combustion chambers the valve dimensions are similar ( though not sure on the stem/guide clearance yet ) but the earlier valves are flat across and not concave so will give less volume so tiny higher ratio ?

Thanks

Peter

Hepolite 23874 suits 3.9 with a comp ratio of 9.35:1.
Comp height: 47.3mm
Bowl depth: 3.32mm
Hope this helps.