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Discussion Starter · #1 ·
After spending all morning reading up on head gaskets and head gasket failures I was wondering a few things. First let me give some background:

MY00 2.5 RS-T. I blew up the stock pistons. I replaced the rods and pistons with forged low compression (8.5:1) replacements. I later found out that the replacement pistons were designed defectively, and needed to be replaced. This past weekend the new pistons went in the motor. Upon inspecting everything it appears the prior set of aftermarket pistons were slightly making contact with the heads, as there were marks on the piston tops and the heads. The valves were fine. In looking at the new pistons, when they are at TDC they are not flush with the block. They actually stick out past the end of the block a small amount (haven't measured it yet). We noticed this after taking all of the pistons out, so I don't know if these stick out further or not than the set I took out.

I would assume that the pistons hitting the heads, would explain a lot of the noise I was getting that everyone was attributing to common "noisy forged pistons".

In reading I have found several references to "stacking" head gaskets, i.e. using two 99+ head gaskets on each side.

My questions are:

Has anyone here actually used multiple head gaskets on each side? What is the expected durability of such a setup?

Do the stock pistons (or anyone who has aftermarket pistons) fit flush with the block or extend past the end of the block a hair? I haven't seen a stock block to compare this to.

I would like to prevent the pistons from hitting the heads, for obvious reasons. So I trying to gather more information.

Thanks,
 

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Discussion Starter · #9 ·
I am going to try a thicker copper head gasket to compensate for the amount the pistons stick out of the block. They stick out about .025" so the head gasket just needs to be about twice as thick as stock to allow the proper clearance.

I realize that this is not the correct way to deal with it, but after 7 months of fighting with the vendor to get this far, I am not willing to wait for several more months for the vendor to try and help me.

I should have the gaskets by the weekend and the motor back in the car. I will let people know how this works, as I have found out I am not the only one with this problem...

Thanks for the suggestions everyone.

Aaron
 
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