I'm building a new motor for the autocross car this winter and the class I run in only allows stock rebuilds. 1st overbore, head and block shaved to factory spec. I also run header and CAI. Most of the cars in the class are the same as my CRX Si so competition is very close and I'm looking for every advantage I can get.

My question is about rod and main bearings. Is there any advantage to building a motor with slightly bigger clearances around the bearings? Will this free up any power? I'm basically thinking about going one size thinner on all the bearings if there is an advantage. The car is nationally competitive so I'm at the point where I'm looking for tenths of a second and every little bit counts. How much longevity will I be giving up if I go with the bigger clearances? TIA, I look forward to the advice.

 

I set mine to the wide side on Hondas spec. It supposed to reduce friction a bit.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chiovnidca &raquo;</TD></TR><TR><TD CLASS="quote">I set mine to the wide side on Hondas spec. It supposed to reduce friction a bit.</TD></TR></TABLE>

Yeah, that's kind of what I was thinking. I'm just trying to decide if I can safely go outside the spec and if there are any gains to be found by doing so.