[axsaxoman]

[QUOTE=dannygti;5800897]Leon cupra R make 13psi standard.. I'd consider nowadays 10psi to be low boost.

Dozens of people have run 14psi on standard internals with no issues. Make of that what you will.. Noone would warranty or guarantee this but from past experience it can be done[/QUOT]
Leon will have either forged pistons as std and they will be totally dif design to a non boosted piston with different size rings and crown thickness etc

this is the main reason that you fit forged pistons , made from different material ,different design ,differnt piston rings and stronger crowns .
I laugh to myself when i see people getting all wound up about comp ratios and fitting decomp plates etc ,when its not the answer .
to the basic problem .
I am quite sure with CORRECT ecu mods /ecu system you can run 7 psi on std comp ratio + std pistons with a turbo
we have done it many times with s/c cars ,so if turbo,s are a problem then it must be down to the way they are set -up and not comp ratio,or inlet temps are too high and the ecu is not compensating for the temp changes in ign + fuelling settings
eventualy they will fail ,due to the design issues .
making it low comp is not addressing the problem an just makes it dull when off boost,
it is just a bodge up to get round fitting proper ecu system and mapping it correctly for the boost level chosen.
and as for decomp plates --waste of money -just fit multiple mls h/gaskets done it maytimes with never a failure ,if you must use std pistons and want to lower the comp.
same goes for ARP h/bolts and nuts and using copper gaskets --the engine was designed to run strech bolts and ovetightening ,which is what you are doing with studs + nuts,as it does not allow for the expansion of the head when hot just stresses the block,and its a weak enough block to start with
I can hear the disbelief --ok then check your cam belt when cold + then when hot and see how much it tightens --that the head expanding ,which is why you use strech bolts to allow this to happen with overstressing the head fixing threads (the block) and to keep same tension on h/gasker when it cools down
its not as though you are running 4bar of boost +nitrous