dishing mahle 94mm pistons

[JIMP]

I have a street engine, n.a.  going to 1914cc from 1.6, , I have the 94mm mahles, std comp height (K70401), as I need cc to lower the compression, how deep can I cut a dish on the crown without being dangerous? Comp will be just below 9:1, I suggest a 70mm circle dish on the crown?, but how much deep would be OK?

Thanks in advance

Dimitrios

[dragvw2180]

 A suggestion would be to add a copper head gasket like we use on turbo engines . They make them in different thicknesses .

[Martin S.]

Why such low compression? I have 9.4:1 in a 1776 with stock 34pict and muffler, which runs great on regular crappy gas. 

[JIMP]

Hello, thanks for inputs, i know that shims would be the easy option, but I just need to maintain something from that squish area, so I need to do it the harder way,

Martin I'm with you actually, you're right, but this specific one will go on a heavy car -bus T2- and the owner also has a heavy foot, so I\m thinking to give it some extra chances to survive!

anyway was thinking for a dish at 70mm x2mm depth, if just someone can verify that this is good or let us with a pretty thin crown, as I measure it the crown will end in like 3mm thick after dishing,

Friendly

Dimitrios

[Martin S.]

I still wouldn't do it. Simply back off the timing until it doesn't ping for the gas you're using and it won't be a problem.
Regardless, my turbo needed a dish and I believe it was cut .070" (1.8mm) using AA slipper skirt (the cheap ones).

[RaptorLou]

[ Attachment: You are not allowed to view attachments ] most pistons are made thicker on top to allow  valve relief. Measure the thickness. These are 94 compression with hi wrist pin CP's
Back in the day I routinely took .100 off Mahle pistons. [ Attachment: You are not allowed to view attachments ]
Lou

[Joel Mohr]

Hemi cut....

[JIMP]

Ok thanks a lot for inputs and pics, I made finally a 2mm deep dish, I hope it holds and will not have problems, the compression came to 9,1:1, that's with an fk8, so I think it wont be a problem,

again thanks a lot for helping

Friendly

Dimitrios