A friend of mine has a Civic Type R (B16B) that is Turbo'd and recently picked up a couple blocks with cranks to build a forged bottom end with. Someone told him the cranks in these cannot be ground and have over size bearings installed. Is this correct? I've never heard of this. Input please.
Not many people have had success grinding Honda cranks and using oversize bearings. Supposedly they often have bearing issues. Supposedly this is because the nitride treatment on the crank journals is not very deep, and grinding it removes this hardened layer making the bearing more likely to spin.
That's just what I've read about it, no first hand knowledge.
My experience is that Honda cranks do not survive machining, even just in street use. Latest example in my life was a B18 Integra I bought for Chump. It had a bit of a rattle on startup, dropped the pan and found worn out undersize bearings. The rebuild didn't look to be terribly old. Found a used engine, rolled a set of standard bearings and rings into it, and it now has about 45 hours on it, with 3 class wins.
Between that, and a few other situations I've been involved in, no machining for me.
The cranks are durable enough not to wear out in street or racing use. The only thing I've seen that damages them is big-end bearing failure. If the engine has been starved of cool oil badly enough to suffer a big-end failure, what else is shot?
You can get oversized bearings, but like mentioned above, grinding the crank goes through the hardening layer and it costs more to re-nitride than buying a brand new crank from Honda (if you can get one)
Gotcha! Thanks for confirming guys.