Who can ID these pistons?

[75Carrera]

My wrench called me over today to show me the tops of the pistons in my 3.2. They have obviously been replaced with what he thinks are "JB" pistions. Can anyone identify these from this picture? If so can you determine what compression they would be? I have to assume they are some sort of upgrade but don't anything else about them.

[jmz]

think he meant J&E not JB. They make alot of aftermarket pistons. No way I can guess at compression but they appear to be failry high domed but not crazy. ...probably in the low 9's :1 compression ratio but that needs to be measuerd by the engine builder not some guy looking at a one dimensional picture on the computer screen.

[75Carrera]

You're right JMZ,
They are J&E pistons. I just looked at their site and sent them an email asking if they can ID them for me. They are either 9.5 or 10.5 since that looks like all they offer. They are nicely domed and cut deep for various cam and valve requirements so my 964 cams or even "S" cams should be just fine.
Good eye... Thanks

[jmz]

they offer any combination ratio you want. they could be anything. check for ID numbers under them.

[75Carrera]

I would like to avoid pulling the cylinders or tearing it down any further if that's reasonable. I had to have the motor pulled to chase a ticking sounds in the values over #4. Turned out to be the valve guides. So far I've found I needed to send the heads out for a complete refresh and just paid over $300 for an aftermarket fan housing. The parts and labor along with costs for re-doing the heads ($620), grinding the cams ($275) and (hopefully nothing else too major) will come to well over $3000. If these pistons are going to work with the 964 cam profiles and be somewhat better than stock 3.2 pistons all is cool. If there's a reason to consider the particular specs on these pistons for some possible conflict with the cams or something else, please clue me in. Sounds like you have some P-smarts. I certainly want a great 3.2 motor in the end.

[David]

Just check the valve clearance by tighting the adjusting screw by the amount of clearance you feel safe with and SLOWLY turn the engine over. If there's no contact, you have enough clearance. From the looks of it that shouldn't be a problem.

[JeremyD]

Doubt you would have a Valve to piston clearance issue with 964 cams and JE pistons - they typically use deep valve pockets.