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Discussion Starter · #1 ·
Had to replace the pistons in a race only 6/71 Blown Dart 434 due to to much timing retard. It has MLS head gaskets and has been together 3 years with numerous 1/4 mile runs. I'm on the fence about weather I should reuse the head gaskets or not. They look good but?
 

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High risk, the gasket has been crushed by its original installation. This crushes the raised embossing which is the part doing the sealing. To some extent extent the embossing springs back when the clamp load is released but not to its original contour. That holds especially around the fire ring where the heat of combustion anneals (softens) the steel. This is especially critical on engines like the SBC where there is the hot spot between the center cylinders caused by the adjacently placed exhaust valves. A failure here, especially, on a blower or juiced motor usually leads to flame carving a ditch through the head or block material or both between these two cylinders.

For a street motor that doesn’t see track time and is not using supercharge or nitrous youre likely to get away with it because the engine isn’t running hard and combustion pressures, heat and temperature are moderate. But for an engine with power adders and is raced this is an invitation to seriously expensive troubles.

Bogie
 

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Race it, Don't rice it!
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Some of the MLS gasket don't have the printo seal or embossing so we need to to know which ones you have. You'll need to make sure the RA finish is right and the faces are still flat.
Likely your ok, honestly, I hate doing things twice and the $200 isn't a lot for the insurance of not doing it again.
 

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Discussion Starter · #4 ·
High risk, the gasket has been crushed by its original installation. This crushes the raised embossing which is the part doing the sealing. To some extent extent the embossing springs back when the clamp load is released but not to its original contour. That holds especially around the fire ring where the heat of combustion anneals (softens) the steel. This is especially critical on engines like the SBC where there is the hot spot between the center cylinders caused by the adjacently placed exhaust valves. A failure here, especially, on a blower or juiced motor usually leads to flame carving a ditch through the head or block material or both between these two cylinders.

For a street motor that doesn’t see track time and is not using supercharge or nitrous youre likely to get away with it because the engine isn’t running hard and combustion pressures, heat and temperature are moderate. But for an engine with power adders and is raced this is an invitation to seriously expensive troubles.

Bogie
I'll get new ones and rest easier. lol
 

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Discussion Starter · #5 ·
Some of the MLS gasket don't have the printo seal or embossing so we need to to know which ones you have. You'll need to make sure the RA finish is right and the faces are still flat.
Likely your ok, honestly, I hate doing things twice and the $200 isn't a lot for the insurance of not doing it again.
No markings to tell which ones I have so I'll just new ones.
 

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More for Less Racer
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If it was to make the next round at a race...clean and copper coat and go with it knowing you can tear it back apart later.

Refresh build though, I'd put new in.
Save the old to the trailer if in good shape, just for an at-track emergency repair if you run for decent dollar amounts.
 
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