Displacement Question?

j0nes

The Courteous Asshole
Driver
I am not to literatured into engine displacement bore and stroke and such things and I was wondering if anyone could just give me the cliftnotes version of it, and no this will not be a how to put stickers w/o air bubbles thread.

I was a little confused today when I was looking through one of the magazines and saw an add for a stroker kit and saw that the KA actually puts out a higher displacement than the SR.

BC BRIAN CROWER STOKER KIT

KA24: 102mm Stroke, 91mm bore and puts out 2.65L of displacement
SR20, 91.0mm Stroke, 89mm bore and puts out 2.31L of displacement

I was always under the impression that a higher displacement usually meant more hp and that bore was for piston size...if im mistaken please correct me its why im asking...
 
displacement is the CCs (cubic centimeters) of the combustion chamber at BDC (bottom dead center). multiply the displacement of one cylinder by the number of total cylinders to get the collective displacement of the engine.

1,000 cc's = 1 liter.

bore is the diameter of a cylinder.


stroke is the travel of the piston from BDC to TDC

no offense with the basic explanations..


i can get the exact formulas for displacement, stroke and bore out of my notebook, but i'm sure you can find them through google if you needed to.
 
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thanks im just confused on why the KA has all higher stats than the SR if the SR is the motor that is most highly used
 
-Sr is more used because its 86X86 (bore stroke) with an 8.5/1 compression. Stock boost is 7psi. Around 205 crank. KA is 86mm bore X 96mm stroke. 9.5/1 compression. N/A 155 crank.
 
omg you just opened a can of worms about as bad as the kat vs sr shit.... sigh... wait till the ca people get in here then all hell is going to break loose.

the main reason that people use the SR's are

the pistons are better designed to with stand more power.
the sqaure stroke(or closest to it) is very stable. 91x89

thats about the biggest points. unless someone wants to add too these.
 
^^^i thought that SR was 86X86. And CA's are garbage. There are like 4 in the country that Idle. We should have left the sub-2-Liters to honda.
 
lol im not trying to start a motor battle and the reason the ca wasnt listed was because it wasnt in the add so therefore i didnt bother to research it. but yea wait till nook sees that last comment
 
^^^i thought that SR was 86X86. And CA's are garbage. There are like 4 in the country that Idle. We should have left the sub-2-Liters to honda.

You're garbage for even saying something like that


but your right SR bore and stroke is 86X86


Jones original question is derived out of the statement "there is no replacement for displacement" and if the KA has bigger potential for displacement increase than why is it not used more.

Mostly because SR's are JDM tyte. Most people Don't want to do internal work to a motor right off the bat. They want a good powerful reliable motor thats easy to install and easy to get parts for.
 
actually i think the answer to these will be ... the ka24DE has a bigger displacement because is a bigger engine..
"...KA24: 102mm Stroke, 91mm bore and puts out 2.65L of displacement
SR20, 91.0mm Stroke, 89mm bore and puts out 2.31L of displacement."
KA24 block can be bored to a certain point where is still realiable and since the engine is 2.4 liters you can add a little more up to 2.65 without compromising the walls. and sr 20 is 2.0 liters so to get to 2.65 will be probably imposible because you could thinned it that much without the posibility of no more space available..

maybe that is the answer .....maybe not... lol but at least i tryed..lol
 
actually i think the answer to these will be ... the ka24DE has a bigger displacement because is a bigger engine..
"...KA24: 102mm Stroke, 91mm bore and puts out 2.65L of displacement
SR20, 91.0mm Stroke, 89mm bore and puts out 2.31L of displacement."
KA24 block can be bored to a certain point where is still realiable and since the engine is 2.4 liters you can add a little more up to 2.65 without compromising the walls. and sr 20 is 2.0 liters so to get to 2.65 will be probably imposible because you could thinned it that much without the posibility of no more space available..

maybe that is the answer .....maybe not... lol but at least i tryed..lol

Yep thats about right
 
ah ok that def makes sense to me, now i understand it...which is good to know lmao!
 
i have to agree ca's are not garbage i even considered getting one at one point and still do.
ya i completely agree with you
i was saying oh man because here goes the war on which motor is best
i like the ca!
i wouldnt mind having one
 
the ca is like any motor you maintain it and it will last, baby skyline motor is what its more like anyways lol
 
I do not like the BC Kits, there nice but with that long of a stroke its basically a drag only motor, the engine wotn rev wroth a shit even with there balanced crank.
the KA would be the best 4 cyclinder motor nisssan has ever made if the motor was squared and turbo. IMHO.
 
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