Head bolts: how to identify torque to yield bolts

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MostMint
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Head bolts: how to identify torque to yield bolts

Post by MostMint »

DF54356A-6DE2-4023-BB00-AC19846B5F7C.jpeg
On the bottom is a bolt I removed from the engine. On the top is a new torque to yield bolt.

How can I tell if the one on the left is torque to yield?

I have a 1995 gen 1 small block Chevy with a cast iron block and cast iron heads and for decades that combination used reusable head bolts. Now they want to sell me the TTY bolts but I want to reuse the factory head bolts assuming they are standard bolts and not TTY. Thoughts ?
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]
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wxo
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Re: Head bolts: how to identify torque to yield bolts

Post by wxo »

I've read several sources on the web who have stated that GM started using TTY head bolts in 1996. I've also read where the TTY bolts have the integrated washer.
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MostMint
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Re: Head bolts: how to identify torque to yield bolts

Post by MostMint »

Thanks WXO. Upon further reflection I realized the bhe bottom bolt is marked. This indicates it is a grade 8 which would not be torque to yield

https://www.youtube.com/watch?v=e3AU-a2Jm8U
[quote="Basement Paul"]Is that a mint rocketship on the hood?? :shock:
-BP[/quote]
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