Long stroke motors don’t want revs. They make torque instead. Plus the KA’s head design isn’t the greatest for high RPM flow. Notice how they fall flat at 5,800?
If you want to build a high RPM screamer, I (and I feel dirty saying this) suggest an NA SR20DE … as long as you toss the valvetrain.
And put it in something smaller and lighter than an S chassis.
so you mean to say…high-revs and torque practically wont come hand in hand (as in the case of civics/prelude etc) or is it due to the oversquare nature of the engine? or did i just repeat myself??? ahhh gotta love working long nights inhaling propane lol
i have this possibly idiotic idea in my mind…how about de-stroke a kA24DE and increase compression?
haha adam its soooo true. any motor that revs to 9k all the time needs rebuilds quite often it seems! I figure the faster you have stuff spinning the faster you’ll have stuff breaking.
As far as motors that like to rev making torque. HP is simply a calculation of torque. The same torque at a higher RPM will make much more HP, oversquare engines dont like to rev because they have such a long stroke, however this long stroke allows them to make more power. Since they can’t rev, this power is seen mostly as torque (due to low rpm)
I hate the SR valvetrain. Such a peice of fucking shit. When i see KA valvetrain i get so jealous. WTF was nissan trying to do here???
The proper rod/stroke ratio should be used as well. A long rod engine should rev better then a short rod engine(assuming everything else is equal). Having longer rods increases dwell time at TDC and lessens piston acceleration.
Build a high revving rotary If you knew that at about 6k rpm the piston accelerates from a stop, past Mach 1, to a stop, and back again, you wouldn’t want a piston engine revving high ever again
I dont know the exact physics formula but i asked this back in grade 12 and basically the more weight you add the force on it goes exponentially up or some shit. so the heavier a motor, even at the same rpm the forces inside are not proportianally higher.
So say you have a 50% bigger motor that is about 50% stronger, well now you have like 4times more force on that peice that is only 50% stronger. so you cant rev as high anymore
this is the reason why displacement and forced induction are better in a crux…
revs increase the load EXPONENTIALLY
forced induction increases the load linerally…due to the angle of the piston to the crank and when power is being applied through the stroke of the engine…