B16A2 rebore needed for new pistons?

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Junior Member
Hey whats up guys?

It's the first time I've posted on this site, but I've been reading up on here for the last few years. I live in the UK and am a proud owner of a 1999 Civic Jordan (limited edition B16A2 powered EK4 Sunlight Yellow hatchback with yellow/black leather interior).

Anyway I am building the engine for boost on stock sleeves, and have recently purchased some CP 9:1 cr 81mm pistons and Eagle rods. I'm only shooting for 300whp and am also building the head with Skunk2 valvetrain and intake manifold.

My question is should I have purchased slightly oversized 81.25mm or 81.5mm pistons and have the cylinders rebored to ensure a better bore, or will I be ok with the stock 81mm? The motor has 95,000 miles on it, and runs strong. No problems with it. A lot of people have told me I shouldn't have purchased stock size. I am hoping I can get away with a hone. Is is true forged pistons expand with heat and require a slight rebore anyway?

I'm really hoping someone can answer these questions for me as you guys have been doing this for years, and here in the UK although we have a big Honda scene we are still catching up! I'll be using Hondata S300 and running a GT28RS.