03 mcs 15%sc, 2% crank , WMW cat back , custom cai , gutted precat , I also ported and polished the TB and gasket matched all the intake bits also the exhaust manifold . Was running about 16 to 17 psi . Eight months ago I bought a junk yard block and a rebuilt head . Had the head thoroughly checked at a machine shop .Car was running great.


About a month or so ago started getting weird coolant issues . Sometime low coolant sometime too much coolant . I knew what was comming . A few days ago I noticed a smell of exhaust fumes in the coolant resv when I opened it . On my way home yesterday the cooling system pressurized enough to blow a radiator hose . Looks like I'm doing another head gasket and this time I'd like to bullet proof it .


1 Anyone know why it only lasted 8 Mos. Too much boost for stock gasket,??
2 Recommendations please on a stronger gasket if that would help or any other upgrades

 

Assuming the head and block surfaces were good (flat) and you followed proper head tightening procedure I'd say the head gasket ain't up to the task.

Years ago before turbo-charging was a thing turbo-charged or supercharged engines were often machined to accept small diameter wire o-rings to seal the cylinders with the gasket having to deal with just keeping the oil and coolant sealed. Then aftermarket gaskets became more common.

You sure the boost control is not letting the boost get too high?

 

There's no boost control that I know of . I was getting 15lbs before the rebuild and 17 after . I didn't have the block checked but it came with a head attached and when I disassembled it the gasket looked good . I used a different head that was rebuilt at a head shop . I dread doing another head gasket so Im considering using this
https://www.fusionsealers.com/mobile-version/index.htm

 

Don't use any sealer. Fix the head gasket right. This means replacement.

Be sure the head and block are flat. I used a Snap On precision straight edge and feeler gauges to determine if the head or block needed machining. Check the block and head surfaces the long axis and short axis and corner to corner for any twist.

Added: Forgot to mention that the head/block and gasket can be ok but the head bolts or studs are not up the task of keeping the head down against the extra pressure of the added boost. It ain't the boost pressure but the increase in combustion pressure generated that is the problem.

With other engines it is quite common to go aftermarket high strength head bolts/studs.

 

[scrolled to far, responded to wrong thread]

 

I hope you changed the head bolts when you replaced the head gasket......... those bolts are torque to yield bolts