Why not more 5 cylinder cars?

[AgaBoogaBoo]

I was thinking how most people either have a 4 or 6 cylinder engine and remembered that Volvos use lots of 5 cylinder engines. (Forget about 8 for this discussion)

Why don't more car manufacturers use 5 cylinder engines? Why does Volvo use 5 cylinder engines instead of 4 or 6?

 

[SunnyD]

5 cyl gives smoother engine characteristics over a 4, but better gas milage over a 6, and power output is someone in between. However it's a different timing system which most motor companies don't want to deal with since they use the same engine/power plant for several different models of car (ie: existing 4cyl engine designs).

Not to mention it's more expensive to manufacture.

 

[CrackRabbit]

I'm no mechanical engineer but i think its because they are a pain to balance and keep smooth. Its also the reason you dont see many Inline 6 engines, my AMC has an inline 6 its the epitomy of unsmooth.

CrackRabbit

 

[Actaeon]

GM uses some Inline 5's. They are used in the Trailblazer and a few other trucks.

I have a few reasons for why its not so mainstream (v6s are probally easier to produce, take up less room with a 3x2 configuration, and probally put out more power anyway), but I really don't know the specifics.

 

[PlatinumGold]

Originally posted by: CrackRabbit
I'm no mechanical engineer but i think its because they are a pain to balance and keep smooth. Its also the reason you dont see many Inline 6 engines, my AMC has an inline 6 its the epitomy of unsmooth.

CrackRabbit

hmmm, i always thought Inline 6's were more balanced than V6's.

of course if you want to talk balance, the Boxer engines are the most balanced of all.

 

[kag]

Originally posted by: Actaeon
GM uses some Inline 5's. They are used in the Trailblazer and a few other trucks.

I have a few reasons for why its not so mainstream (v6s are probally easier to produce, take up less room with a 3x2 configuration, and probally put out more power anyway), but I really don't know the specifics.

I believe the Trailblazer/Envoy/Bravada comes with an inline-6 engine pumping 270 or so HP.

BMW doesn't produce V6, only inline 6s... and I don't think BMW is known for their rough engines
And the M3 is also an inline 6 and it produces 333 HP... more than any production V6 that I can think of on top of my head.

 

[vi edit]

GM uses some Inline 5's. They are used in the Trailblazer and a few other trucks.

It's an inline 6 in the Trailblazer/Envoy and an I5 in the Canyon/Colorado small pickups.

As for why not do it? Dunno. Probably because it's just simply easier to refresh an existing engine that's been in service for a couple of decades than it is to redesign and start fresh.

 

[jeece]

Audi too made 5 cyl. engines. And I guess other manufacturers did some too.

The only reason I can think of is the odd number of cylinder, making the engine to run less smooth (because of the 4 strokes being distributed among 5 cylinders).

I don't say it's an absolute fact, it's just my theory.

 

[Pepsi90919]

Originally posted by: vi_edit

GM uses some Inline 5's. They are used in the Trailblazer and a few other trucks.

It's an inline 6 in the Trailblazer/Envoy and an I5 in the Canyon/Colorado small pickups.

As for why not do it? Dunno. Probably because it's just simply easier to refresh an existing engine that's been in service for a couple of decades than it is to redesign and start fresh.

i thought it was the 4.3 V6 in the blazer

 

[vi edit]

i thought it was the 4.3 V6 in the blazer

Old Blazers/Jimmy's yes. The redesigned Trailblazers/Envoy's/Bravadas that came out three years ago or so have the new 4.2L I6.

 

[her209]

Why not more rotary engines?

 

[notfred]

Originally posted by: her209
Why not more rotary engines?

They fall apart way too quickly.

 

[vi edit]

Originally posted by: her209
Why not more rotary engines?

Outside of specialy sports cars they aren't practical. High HP + 0 torque = not fun driving on most highways and in town stop & go traffic. It's a purpose built engine. And that purpose wasn't to be put in your Mom's minivan or Camry.

 

[Demon-Xanth]

I-5's don't have any odvious advantages. I-6s are inherantly smooth, they don't need extra balencing that the other engine configurations have. A rough I-6 probably has NO balencing, whereas a V6 without tons of balencing would tear itself apart.

 

[CtK]

my friend use to have a Acura Vigor and that had a 5 cylinder engine
it was quite smooth

 

[Kremlar]

High HP + 0 torque = not fun driving on most highways and in town stop & go traffic.

I wouldn't say ZERO torgue, but torque certainly isn't a rotary's strong point. No fun to drive though??? Where does that come from?

They fall apart way too quickly.

Bull.

 

[HiTek21]

Originally posted by: CtK
my friend use to have a Acura Vigor and that had a 5 cylinder engine
it was quite smooth

the 2.5 TL was basically the same as the vigor just rebadged like the legend was rebadged RL

 

[Rage187]

Acura Legend was 5 cylinder AFAIK

 

[SunnyD]

Originally posted by: notfred

Originally posted by: her209
Why not more rotary engines?

They fall apart way too quickly.

Uh, I believe due to the absence of lots of little moving parts that are inherent in inlines and V's, rotaries actually last LONGER.

 

[Colt45]

My old Audi had a turbocharged I-5.

supposedly the idea was the economy of a 4, power of a 6.
I dont think the economy part worked.

 

[Triumph]

There's really not much point in an I-5 nowadays. You can do everything you need to do with a I4, V6, or I6. As someone said, there's just no obvious advantage of an I5.

 

[Nebor]

I i5 is just a cool Volvo thing. Keep in mind that the inline 6 is a dying thing. Only Volvo, and BMW still produce them, as far as I know. Jaguar has gone to a v6, Saab only has i4s, Audi is all v6s... Volvo's 2.9l i6 and BMWs 2.3l, 2.5l, and 3.0l are all that remain of the i6...

BTW, Volvo's i5 can put out 333hp in the S60r, so it's nothing to discard.

 

[zixxer]

It is a turbocharged engine thing. Look at saab and volvo. iirc it has to do with gaining boost at lower rpm's or something

 

[Howard]

Originally posted by: her209
Why not more rotary engines?

Very low thermal efficiency.

 

[Howard]

Originally posted by: armatron
It is a turbocharged engine thing. Look at saab and volvo. iirc it has to do with gaining boost at lower rpm's or something

What the hell?