Boost pressure.. how much?
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Boost pressure.. how much?
Hey guys, i'm not really sure if this has been beaten to death yet or not. I'm pretty sure it has, but i didn't find anything in my quick search.
How much boost can the stock head gasket hold?
i was going to go with a 3mm gasket but then thought i would just be filling that void with more air and fuel and not getting much more power for the price. I do intend to fully build the motor next fall/winter but i'm just getting the new feeling out me and kind of trouble shooting the setup i have now.
Also, i was only going to run 8psi to be on the safe side, but decided to get closer to 10.. peaks 9.7 or so according to the AEM truboost.
also, not sure if it matters to the question, but i did studs.
TIA
-Craig
How much boost can the stock head gasket hold?
i was going to go with a 3mm gasket but then thought i would just be filling that void with more air and fuel and not getting much more power for the price. I do intend to fully build the motor next fall/winter but i'm just getting the new feeling out me and kind of trouble shooting the setup i have now.
Also, i was only going to run 8psi to be on the safe side, but decided to get closer to 10.. peaks 9.7 or so according to the AEM truboost.
also, not sure if it matters to the question, but i did studs.
TIA
-Craig
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Joined: Feb 2010
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From: NY
I wouldn't say a ton more but you'll be fine at 10psi. Common consensus is 12-14 psi to be safe on stock compression. Btw if you have e85 available to you don't build the motor, Today I actually started to finish assembling my built motor and if I had todo it all over I'd just find a healthy f20c do head studs and run e85 and plenty of boost and would have saved a lot of money. Currently I'm just shooting for limits on pump gas which should be around 520-540whp, anyway sorry for the long story just trying to edumacate you from my experiences 
-Chris
-Chris
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Joined: Oct 2007
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From: Mooresville, NC
Op didn't specify pump gas from what I can tell. Asked what boost limit the oem head gasket can take which has been proven to be MUCH more than 10 psi.
If on pump gas many would say 14 psi or so would be a good safe limit.
If on pump gas many would say 14 psi or so would be a good safe limit.
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Stock hg can hold 20-25+, that's not the right question, the right question is how much boost can the motor take before it starts detonating and you run out of timing retard to compensate for it. That depends on the fuel your running. Pump, 12-15psi. Some have a different idea of what they consider safe.
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Joined: Jul 2009
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From: Roswell
My car was running 16 psi for a while and now 15.3 psi. I believe the comfortable limit on 93 is somewhere around 12-16psi. Boost is not what is actually going in but the back pressure of what isn't going in. It's really hard to say what a safe pressure is as there are so many variables to consider like elevation, temp, octane, turbo size, manifold, etc,etc.
