Gn1r third generation heads....14 bolt...what power level?

[Nakamichiman]

What power level will gn1r heads support before cracking......They are third generation heads? Anybody have any experience with them......I've been told they have been on cars in the 8's but not confirmed.....

 

[Nakamichiman]

They are not the latest generation....not sure if the newest ones are 5th or 6th....