Just trying to clear some things up ...

Now, to my understanding there's 2 ways to increase displacement. Either stroker kit or boring out the cylinders. Is that correct?

If I can continue .... with a stroker kit, your basically increasing displacement by lengthing the cylinders. And that's why the rod/stroke ratio decrasees? Is that correct?

Now with the latter ... by boring out the cylinders your increaseing the displacement. What are the side effects besides the strength of the walls?

Why would people stroke a motor over boring it? I think Enydn has some 84 (??) pistons that would make a 1.8 a 2.0 liter motor ...

Thanks

 

It's a matter of choice. B20 blocks are easier to find than 88-91 Prelude cranks, IMO. I've been itching to do a b20 w/ 84.5mm pistons and a 95.0mm crank. 2130cc displacement. some ITR cams. rev it to 8000.. see you in my rearview. lol.
but basically, back to stroke vs. bore...

by what i've seen and heard.. take two motors.. equal displacement, equal compression, etc.. give one a small bore and big stroke, and give the other a big bore and small stroke..

the stroked one will make more low end and have some serious peak torque... but the torque will drop off more dramatically as you rev it higher and higher..

the bored one will see a similar torque/power band of the stock motor.. only higher by 10-15 everywhere. this motor will also make more high end torque because the pistons are at TDC longer. perfect example is a b16a vs. a LS/VTEC..
put some spec B or jun3 or whatever in the b16a.. the b16 might not make gobs of torque.. but the torque basically "keeps" itself up, whereas the LS bottom will start to diminish in torque past 8000, and my guess is.. by 9200 or so, the motors will be making the same torque.

if you study some dyno graphs you'll be able to see the difference even between a 87.2mm gsr/itr stroke and a 89.0mm b18b stroke.

larger stroke makes mad torque but loses steam quick.

another point of rod/stroke ratio comes to mind.. the longer the rod and the higher the ratio, the better. look at the b16b. with the geometry of that motor, i'm sure 10,000rpm is feasible. nice long rods, tight stroke..

bottom line is.. its your call. if you're gonna be rebuilding the motor every season, go all out with bore and stroke increase. for reliability.. i'd stay with stock crank and bore increase.