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HI
I know everyone says to use a 2mm mhg when turboing a 5mge.
I was wondering if there would be any improvment if someone used a normal (stock) 7mgte head gasket on a turboed 5m?
I can get a new one cheap, so if it will work good (im not looking for insane boost, want to get 230-250rwhp) then will this be good, or will there be no improvement over having a 5m head gasket?
Also, what is the thickness of a stock 7m head gasket?

THANKS
 

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Stock thickness is 1.5mm....

A MHG is a nice safeguard against a BHG, esp under boost conditions.

Improvements??? Not really, esp since a 1.5mm will raise your compression, you want to lower it, on a turbo application.
 

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I'm using a 7mgte HG on my 5mgte. I wasn't going to put the money into proper machining for a MHG. The feel of a 5m HG was very flimsy when directly compared to the 7m HG (and I did pop my 5m HG just prior to Vegas...but I was overboosting too with a dead wastegate actuator, and detonating)

On MkIII's, it's generally accepted that the stock HG and head torqued to at least 72ft/lbs is good out to 12psi boost. Some have run more, but I consider this a safe limit. On a later 5m, this should be good to just under 10psi (roughly the same effective compression ratio)....unless detonation is present, then all bets are off.
 
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