HOW MUCH BOOST WILL SAFELY HOLD AN STOCK HEAD GASKET ON A EVO IX

 

Buschur, STM and numerous other shops only run stock. I've seen 48psi hold fine on the stock head gasket....

I as well run stock

 

Daaaamn..... So 25 psi won't hurt anything, or have any issue, like over heating.

 

The head gasket will hold its the head bolts that tend to be the problem. If you plan on boosting more than 25 psi then upgrade the head bolts

 

im just thinking 25 or below no more than that!!! im gonna tune my evo but i was thinking below 25 if possible

 

Tune Below 25 psi?? You must not like power lol

 

Its not about air pressure, its more about air volume.... 25psi on a stock turbo is a hige difference from 25psi on 42r

More volume= higher cylinder pressure

 

Its not about air pressure, its about detonation. Detonation is what lifts a head.

 

Detonation will waste a head gasket for sure, and the engine components-- you need to rethink your air pressure statement . If that was the case then you could run infinite amount of boost without detonation and you would be fine---which isn't the case. The old formula cars used to run solid blocks--heads welded on or machined as one piece due to turbos. Detonation would have engine parts all over the ground at 15-20k rpm---that rarely happened. The guy who posted the response with headbolts has the rt idea--its preperation for the intended use that keeps things together along with quality parts and attention to detail.

 

I never said it was about air pressure (boost). Im talking cylinder pressure. All these things play a role in it, even detonation.

 

Lets say someone is doing a build ............

Larger intercooler to cool the intake charge – to avoid detonation
New fuel pump and new injectors to keep the engine rich – to avoid detonation
Bigger turbo to move more air but also more efficient (less heating) – to avoid detonation
Head studs to hold the head down – in case of detonation
Forged pistons – in case of detonation
Run race gas or switch to E85 – higher octane to avoid detonation
Have a tune – adjust programming for the most power while avoiding detonation
Logging software or a flashing light on the dash – to warn the driver of detonation

 

This is correct.

 

745whp, stock head gasket....

 

Correct, I don't tune customer cars over 27psi unless they have upgraded head studs.

Technically you are both right. Cylinder pressure will pop a head gasket but usually only if it doesn't have upgraded head studs. On built motors if you run high timing at peak tq (=high cylinder pressure) then you run a higher chance of blowing the gasket as well. Also the larger bore motor you go with plays a big roll in how much cylinder pressure your car will take before the head gasket decides it wants to let go. On Built motors, a 2.0 for example we can run 4-5* at peak tq with no problem with the head gaskets. On the 2.4s that have the 87mm bore I don't like to go above 0-1* at peak tq. On my personal car I actually run -1*.

At the same time, detonation is one of the biggest reasons for raising the head. The best fix for that... A good tuner

Mikey

 

X2 ^ you know your stuff Mikey. Listen to this guy... When is that site gonna be up and running?