Just out of curiousity, I am planning on boosting the 5S and am wondering if it is worth opening up the engine just to change the head gasket to a metal one? I mean isn't there some benefit to keeping the engine sealed up? Is it worth just leaving it until it fails (if it does)?

Any idea under what pressure the non-metal head gasket would fail? I have tried searching for information on the topic of keeping the non metal gasket, but everywhere I read just says to put in a metal head gasket when going with a turbo.

Just looking for some feedback.
Thanks.

This post has been edited by WALKER: May 2, 2007 - 1:04 PM

there is no need to do it. its not really a weak point of the setup. so save your time and money and put it into a better tune and lots of dyno time. if it ever blows, then you can upgrade to a metal one.

good idea? yes
necessary? no

so if you have a few extra hours and ~100 dollars
it could prevent u from being stuck on the side of the road one day

metal Hg is a good thing to have, especially for higher boost.
There is no benefit to having a paper/fiber w/e gasket over a metal one.
ok i lied... i guess cost and installation. its also a good piece of mind.

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so are forged pistons, stronger rods, ems, etc...etc....etc... its not like the HG is the 5sfe's only weak point. i would rather stop any detonation from happening then to have a poor tune thats held together by a good head gasket.

when i had my 5sfte set up i had my stock head gasket on and it was fine untill it got weak and blew out between the 3 and 4 cylinders.... then i changed it to a metal one. at the time my engine had something like 170 miles on it with a mild rebuild (crank gave way before the turbo and thus was changed via a warranty company, all they did was pull the crank from the bottom or so it appear when i took the head off)

btw i was running around 12 psi at the time.

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I definately am not going to cheap out on dyno time or tune, as a matter of fact I am not planning on cheaping out on anything.

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What is the failure mechanism when it blows out? What do you observe when it occurs?

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who said anything about detonation? im not saying sacrifice one thing for another.
he asked whether or not its a good idea to have a metal hg. and it is in any light.

its not a somthing you HAVE to have, but, it is a good thing to have if your planning on running higher boost (12+ lbs) ofte, IMO.

if ur HG goes boom
your car will overheat...symptoms arn't always the same depends on the size of the leak. compression between the cylinders drops, excessive overheating = cracked cylinders

and lagos you keep trying to bring in weak point, trade off, blah blah....not the subject

plain and simple
is it worth changing out for a metal one? yes


This post has been edited by playr158: May 2, 2007 - 5:30 PM

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Ive got a metal head gasket for a newer 5s-fe if your interested. Its brand new and oem from toyota.

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I'll start by saying a MHG is stronger than a regular one.

BUT, there are reasons why you shouldn't change it right now.

Consider this

90% of the time an engine is sealed best from the factory, and pulling something to change a gasket that isn't leaking can lead to other problems [and the new gasket leaking].

For your engine [5SFE] if you do blow the HG and you do overheat [blowing the HG does NOT always cause overheating, though normally it does, it depends where it leaks to], it's very unlikely that you will crack or break anything [other than possibly warping the head].
Unless you do something such as keep running it hard.

Removing the head can cause it to warp [not likely unless you remove the bolts in the wrong order].

The regular HG should hold up fine for a while under low boost [6 PSI?] assuming you have detonation under control.

A MHG is more sensitive to variations in the sealing surface than regular ones. It doesn't conform as well to the surface. If it doesn't conform, it doesn't seal as well.

If it was my engine, I probably wouldn't replace it right now, I'd wait for a rebuild or it to blow.

If you don't replace it now, plan to have it blow at any time, and have the parts ready if it's your only car.

I'm not in any way telling you that MHG are bad, or that you shouldn't put one in your engine.
It's definitely not a bad idea.
I'm trying to inform you so you can make your own educated decision.

Thanks for all your thoughts.

I think it is best to keep it sealed up for now and I will be ready for when it blows and at that time will most likely get a complete rebuild and go for metal head gasket.

I just didn't think it would be worth it to pull it apart right now when it isn't leaking and there are no problems.