engines.inline vs v's vs boxer/flats

[brendan89]

hi guys...noobie here...
i would appreciate if some sifu can help me better understand the characteristics of rpm,hp and torque on different variation of engines.

1.)whats the difference of an inline 4 and inline 6 of the same cc.
for this case, sr20 and rb20.

2.)of the same cc..can somebody explain the difference of v's, flats and inlines..
their characteristics in terms of hp,torgue and rpm.
for the sake of argument..
i use these engines..(6a12 vs 4g63 vs ej20) all of them being dohc..

or perhaps recommend me a book. :)

 

[papagoines]

hi guys...noobie here...
1.)whats the difference of an inline 4 and inline 6 of the same cc.
for this case, sr20 and rb20.

Maybe dis one I can answer... I can't remember when or who told me but torque curve has something to do with the piston size, irregardless of numbers... the bigger they are.. the lower the torque/power peak arrive in the rpm range.. or something like that :hmmmm:

Based on my experience as a kei-car lover, there always debate whether going 3cyl vs 4 cyl ... all 660cc turbo DOHC with 4 valve per cylinder... and both engine came from the same chassis which is Daihatsu Mira L502

EF-RL
3 cyl turbo
4 valve per cyl
Bore = 68mm
Stroke = 60.5mm
Max.power (Net) = 64 ps (47.07 kw) / 6800 rpm
Max.torque(Net) = 10.7 kg*m (104.93 N*m) / 4000 rpm

JB-JL
4 cyl turbo
4 valve per cyl
Bore = 61mm
Stroke = 60.5mm
Max.power (Net) = 64 ps (47.07 kw) / 7500 rpm
Max.torque(Net) = 10.2 kg*m (100.03 N*m) / 4000 rpm

As you can see the 3cyl one achieve the same peak hp but at lower rpm range.... and the torque peak is higher in the same rpm range....

I think I've also seen debate of putting SR20DET vs RB20DET in a Cefiro... person favors nice fat torque should use SR20DET, person favors high peak hp should opt for RB20DET... or so the argument goes...

sorry for trolling your thread... just sharing what I know, correct me if I'm wrong

p/s: one thing for certain though, more cylinder it gets more smooth it can rev up ....

 

[brendan89]

Maybe dis one I can answer... I can't remember when or who told me but torque curve has something to do with the piston size, irregardless of numbers... the bigger they are.. the lower the torque/power peak arrive in the rpm range.. or something like that :hmmmm:

Based on my experience as a kei-car lover, there always debate whether going 3cyl vs 4 cyl ... all 660cc turbo DOHC with 4 valve per cylinder... and both engine came from the same chassis which is Daihatsu Mira L502


As you can see the 3cyl one achieve the same peak hp but at lower rpm range.... and the torque peak is higher in the same rpm range....

I think I've also seen debate of putting SR20DET vs RB20DET in a Cefiro... person favors nice fat torque should use SR20DET, person favors high peak hp should opt for RB20DET... or so the argument goes...

sorry for trolling your thread... just sharing what I know, correct me if I'm wrong

p/s: one thing for certain though, more cylinder it gets more smooth it can rev up ....

haha, its ok keep trollng.
i see. that makes sense as far as str8's are concern.
so for low rpm, 4 pistons yield greater torque..as compared 2 inline 6 counterpart of the same cc..
i noticed that in sr20s vs rb20s spec sheet...
rb20's from r32 skylines 215ps@6400rpm and 264 Nm @ 3200rpm

sr20 redtop from s13 silvia 91-93 202hp@6000rpm and 275 Nm @ 4000rpm
which is about right
however,

sr20 redtop from pulsar gti-r 90-94 227hp@6400rpm and 280Nm @ 4800rpm
howcome?
means to say, pulsar gtir>skyline r32?

 

[papagoines]

If i'm not mistaken, GTI-R's SR20DET is tuned more aggresively for example bigger injectors, bigger turbo, and quad throttle body... befitting its homologation to enter WRC's Grp A (source: https://en.wikipedia.org/wiki/Nissan_Pulsar_GTI-R

Maybe that's the case?

haha, its ok keep trollng.
i see. that makes sense as far as str8's are concern.
so for low rpm, 4 pistons yield greater torque..as compared 2 inline 6 counterpart of the same cc..
i noticed that in sr20s vs rb20s spec sheet...
rb20's from r32 skylines 215ps@6400rpm and 264 Nm @ 3200rpm

sr20 redtop from s13 silvia 91-93 202hp@6000rpm and 275 Nm @ 4000rpm
which is about right
however,

sr20 redtop from pulsar gti-r 90-94 227hp@6400rpm and 280Nm @ 4800rpm
howcome?
means to say, pulsar gtir>skyline r32?

 

[brendan89]

If i'm not mistaken, GTI-R's SR20DET is tuned more aggresively for example bigger injectors, bigger turbo, and quad throttle body... befitting its homologation to enter WRC's Grp A (source: https://en.wikipedia.org/wiki/Nissan_Pulsar_GTI-R

Maybe that's the case?

yeah wei.
these pulsars make great sleepers.
no show all go :p