2.2 v. 2.4 pistons

[tharbert]

Can anyone verify the visual difference between a 84mm 2.4T piston and an 84mm 2.2E piston. My guess is that the higher compression 2.2 piston is domed where the other is not?

Assuming this is an 84mm, does the dome definitively mean 2.2E?

Are there other measurements to verify?



Is it better to buy p/c's or can honing the jugs and replacing the pistons be as reliable? That is, as long as my OEM jugs are still serviceable...

Thanks in advance!

[304065]

what is the mahle number underneath

[356RS]

You can measure the piston "h" dimension. In other words the length of the skirt. The 2.2T Mahle is 11.5mm and the 2.4T Mahle is 8mm.

[tharbert]

All I have is a picture. I'm trying to positively identify as the owned doesn't sound too sure.

I think the casting number is: 34V51C021

[tharbert]

I was googling cross reference numbers for Mahle pistons and entry from the technical board had the answer.

It appears what looks like a 3 is probably an 8. According to tom1394racing's post, 84C51 is indeed a 2.2E.

So, are these a straight swap that will accept wrist pins and all? Pros? cons? Other considerations?

[tom1394racing]

Here's some pics showing the valve pocket and dome differences for 2.2 and 2.4 pistons.





The 84V51 is the 2.2E version.