D-Series Bore Questions.

[Jay7]

I wonder if there are any D-series Gurus on this forum. I've been doing alil research and I want to find out if anyone has openedup the bore of of a d-series motor. I have read that the stock bore is 77mm then other places read it is 75mm. I want to find out what the biggest bore anyone has used on a d-series. I want to take a stock d-series motor and try and pull out 200whp n/a out of it. Sounds like a hard tast but I personally think its possible with the vtec models. Anyone care to shead some light on the topic?

Jay7..

 

[phunky.buddha]

75mm is the stock bore for all D series engines. You can even look it up on Honda's own technical pages.

Bores have been taken as high as 80mm for the adventurous people, but most stop at 78mm or 79mm. Quite a few resleeved boosted D blocks are running 78mm bores.

If you want to get 200whp NA out of your D, I would suggest going with the largest bore you can stomach, dropping in a D17 crank and rods, then making absolutely sure that the bearings are spec'd out perfectly so you can still rev to 8000 on the longer stroke D17 crank.

With the right headwork and cam profile, you might be able to get there. Good luck.