Oversquare turbo diesel engine V.S. Undersquare turbo diesel engine

[HUMABOL KA]

i know na ang ideal for diesel engines ay undersquare to produce more torque, but i see some oversquare diesel engines as well,may advantage dn ba ito compared sa undersquare diesel engines?

[jick.cejoco]

I think you have it backward. Over square has longer stroke than the piston diameter for higher torque due to a longer crank throw but is not suitable for higher sppeds

[lowslowbenz]

For starters, here's a good read.

Stroke ratio - Wikipedia, the free encyclopedia

[niky]

No, oversquare has bigger bore than stroke.

Typically provide for more revs, but other factors affect this, also.

[jick.cejoco]

No, oversquare has bigger bore than stroke.

Typically provide for more revs, but other factors affect this, also.

Thanks, I stand corrected

[HUMABOL KA]

No, oversquare has bigger bore than stroke.

Typically provide for more revs, but other factors affect this, also.

un dn ang sabi sa mga nabasa ko sa ibang forums and sabi dn nila na an oversquare engine produces more peak hp power at high revs compared to an undersquare engine is that true sir?

[JR318]

i know na ang ideal for diesel engines ay undersquare to produce more torque, but i see some oversquare diesel engines as well,may advantage dn ba ito compared sa undersquare diesel engines?

Sir very technical na pu yung term nyu na UNDERSQUARE,OVER SQUARE for diesel engine ..

xenxa na pu paki paliwanag pu ng mabuti para sa amin na d nakakaalam..TY

[HUMABOL KA]

Sir very technical na pu yung term nyu na UNDERSQUARE,OVER SQUARE for diesel engine ..

xenxa na pu paki paliwanag pu ng mabuti para sa amin na d nakakaalam..TY

UNDERSQUARE= engine with a longer stroke but smaller bore
OVERSQUARE= engine with a shorter stroke but bigger bore

[HUMABOL KA]

Sir very technical na pu yung term nyu na UNDERSQUARE,OVER SQUARE for diesel engine ..

xenxa na pu paki paliwanag pu ng mabuti para sa amin na d nakakaalam..TY

Double post

[miked]

sa tingin ko e depende na iyan sa application. kung sa akin lamang e i would prefer undersquare than over. mas relaxed idrive ang undersquare lalo na sa hill climb with a heavy load.

pero kung need for speed ka e oversquare.

brader JR318, yung UNDERsquare e mas malaki dimension ng stroke kesa cylinder bore (diameter ng piston). ibig sabihin mas malaki ang buwelo ng piston during the power stroke.

kung OVERsquare naman e mas mabilis nyang tapusin ang apat na stroke sa isang cycle ("mas mabilis ang ikot ng makina")

may mga factors pa rin na makakaapekto sa bawat isa. kaso dudugo na ilong ko sa usapang iyon. hanggan jan na lang. hehe

[JR318]

sa tingin ko e depende na iyan sa application. kung sa akin lamang e i would prefer undersquare than over. mas relaxed idrive ang undersquare lalo na sa hill climb with a heavy load.

pero kung need for speed ka e oversquare.

brader JR318, yung UNDERsquare e mas malaki dimension ng stroke kesa cylinder bore (diameter ng piston). ibig sabihin mas malaki ang buwelo ng piston during the power stroke.

kung OVERsquare naman e mas mabilis nyang tapusin ang apat na stroke sa isang cycle ("mas mabilis ang ikot ng makina")

may mga factors pa rin na makakaapekto sa bawat isa. kaso dudugo na ilong ko sa usapang iyon. hanggan jan na lang. hehe

Salamat po brother MIKE, isa pang tanong sir yung oto kong hyundai SF3 oversquare po ba?
kasi sobrang tulin e jeje.TIA

[niky]

Doesn't really matter when talking about diesels, anyway.

Most modern diesels I can think of are either undersquare or massively undersquare. It's very difficult to make an engine that can withstand the stress involved when you rev a diesel past 5k rpm... so there's no real need to make an oversquare diesel.

[jut703]

As end-users, what matters is how the car drives - whether it's torquey, rev-happy, etc. Which is why people are better off seeing the horsepower and torque figures as well as the respective powerbands. But even then, paper specs don't always translate to real world performance so an actual test drive is still the best indicator of how an engine performs.

Unless you build your own engine you don't really have a choice regarding its bore and stroke. And even then, bore and stroke aren't the only things that define an engine's characteristics.