Can I just check.... looking at the photo / image you posted 3 weeks ago with the 2 pistons sectioned through, is a 16v piston dished - as shown in the image? I thought from memory they were flat across the top??
Hi, this post is very interesting.Yes the 16v piston is dished, just not as much as the 8v, like the picture suggests
I'm doing the same calculations as i have a project motor 8v to be bored to 89mm to accept Nissan pistons (from for example 240SX) that are in all other ways compatible but have 1mm lower compression height (distance piston pin to top of piston) and I will be using reworked 1.5 105HP heads that have the same valves as the 1700 8v heads but are almost flat where the 1700 heads have a compression chamber, it's like the same puzzle as yours and in the end I think I will have to do the measuring with paraffin.
This may help.
I've made a note that the id of a 16V gasket is 88.15mm. Compressed gasket thickness I have as being 1.4mm at 65lbs/ft
Cylinder head capacity is 28.8cc
With these figures you should be able to back calc the capacity of a 16V piston
On my rallycar engine we had pistons out of block by 0.37mm
I reckon on a std bore for every 0.1mm the piston is above / below the block the CR will change by 0.11. Standard CR is 10.1:1
Hi, very neat work!Ok.... so recent progress.
I took the 8v pistons to the engine builders and had them cut to represent the 16v pistons - if that makes sense.
Here is an 8v piston that has been machined to take a 16v valve configuration. Was unbelievably expensive to have this done - but considerably cheaper than buying completely new pistons. Any thoughts......