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Helllo

so there are a few people who know my story, but to sum it up, i have an N1 block thats already at 87mm bore size (40 thou over). There is some damage to cylinder 1 and to reuse it, it would require re-boreing it out to 87.5 (60thou over). Ive been told by some people that this is a big no go, as the block gets too hot under load and will crack, however i've also been told that the HKS / Tomei stroker kits specify an 88mm bore to be used (80 thou over).

Does anybody have any experience with boring out an N1 rb26 to this size ? Keep in mind, this will be used for a fair bit of track work. Any comments/feedback ?

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Helllo

so there are a few people who know my story, but to sum it up, i have an N1 block thats already at 87mm bore size (40 thou over). There is some damage to cylinder 1 and to reuse it, it would require re-boreing it out to 87.5 (60thou over). Ive been told by some people that this is a big no go, as the block gets too hot under load and will crack, however i've also been told that the HKS / Tomei stroker kits specify an 88mm bore to be used (80 thou over).

Does anybody have any experience with boring out an N1 rb26 to this size ? Keep in mind, this will be used for a fair bit of track work. Any comments/feedback ?

You have 2 options keep the 87mm bore size on 5 pistons bore out no1 to 88mm and sleve it down to 87 or bore them all out to 88mm and sleve them down to 86mm or 86.5mm

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