Difference between I4 and V4...

[Pastore]

Saw it in another thread and I never knew there was a difference... Can someone explain it to me?

Oh, and BTW, I did run a search on Google and didnt find anything useful...

 

[vi edit]

Ummm, I4 would be four cylinders in a straight line, V4 would be two sets of cylinders meeting in a "V" configuration.

Typically, "I" configurations yield more effiencient use of the engines which in turn produces better torque and horsepower specs.

 

[jaybert]

wow, why did you post this like 6 times??

 

[Pastore]

i didnt mean too... i hit post thread and it didnt freakin go...

 

[SSP]

Itchy fingers.

 

[snakesnfrogs]

Nobody that I'm aware of still makes a V4---Saab used to, but that was probably at least 20 years ago

 

[Pastore]

so all new engines are inline 4's?

 

[Colt45]

<< so all new engines are inline 4's? >>



all that i know of at least..
there is still some boxsters though..

 

[geno]

<< so all new engines are inline 4's? >>


yes

Colt reminded me, Subaru does have a Flat 4, they call it the Boxer. It's just like a V 4 except for the cylindars are at a 180* angle.

 

[goodoptics]

anybody remembers that the older Mazda RX7 has rotary engine? I think it's a 4-cylinder one.

 

[CattyKathy]

how come u have some many of this thread? I have a I4

 

[geno]

<< anybody remembers that the older Mazda RX7 has rotary engine? I think it's a 4-cylinder one. >>


The rotary engines aren't broken down into cylindars. They have rotars, which the RX7's engine has 2. There are higher performance versions of the Rotary engine that have 3 rotars, I don't know if Mazda has gon any higher yet...

 

[Noriaki]

<< Ummm, I4 would be four cylinders in a straight line, V4 would be two sets of cylinders meeting in a &quot;V&quot; configuration.

Typically, &quot;I&quot; configurations yield more effiencient use of the engines which in turn produces better torque and horsepower specs. >>

Precisely. Inline configs yeild less 2nd and 3rd order vibrations (which are just wasted energy). Bigger engines like V8s and most 6 cyls are Vs because having that many cylinders in a row would make an extremely long block. The V config lets you make a shorter (although wider) block.

There are some I6s floating around, and they have kind of funny shaped blocks, they look kind of long and narrow.

But yes Vi is exactly correct, inline is better than a V, it's just kind of doesn't fit with a lot cylinders inline.


Mazda stopped producing the RX7 and with it the Rotary engine. Because so few of them were built (relative to the amount of cars Mazda produced I mean, it's not that the RX7 was a rare car, just the only one with Rotary), maintenance was very expensive, because not many people have the skills to work on rotary engines, and parts are less common.
So Mazda finally disconintued it, and stopped building rotary engines.
Insane volumetric effeciency though, the RX7 has a 1.2L engine or something insanely low like that.

Very nice car though.

 

[Demon-Xanth]

Jeep still uses a straight 6, as does the new Chevy Trailblazer engine, and Dodge's diesel. Straight 8s were only used in extremely high end cars back in the 20's and 30's. The blocks were quite heavy and quite long. An advantage of the V configuration is a lighter block due to it having less outside wall space. There were some W engines (3 banks of cylinders) and radial engines, but I think those stayed in tractors and aircraft.

And when dealing with the displacement of rotary engines, you effectively have to multiply the displacement by 8/3 to get the effective displacement (since the rotar is in multiple stages of the otto cycle at any given time)

 

[geno]

Noriaki, the new RX8 (successor to the RX7) will have a Rotary engine as well

 

[Doggiedog]

Lots of cars have inline sixes. BMW, MB, Lexus to name a few.

There are V4 engines made for motorcycles though I can't recall any made for cars. Perhaps there may be some Japanese microcars that use V4s.

 

[Windogg]

VW is going to release some &quot;W&quot; engines soon.

Inline engines are also more balanced. The cylinders move up and down rather than out at an angle like V engines. The firing order, especially in V6s, of the cylinders plus rotation of the crank shaft can lead to harshness. This is one of the reasons why higher end luxury and performance cars prefer I6s rather than V6s.

 

[Noriaki]

Cool I didn't know there was goin to be an RX8
I thought that line was just dead.

Have any links or anything about it?

 

[freebee]

I think the flat-4s seen in Porshes and Subaru's are referred to as H-4. In terms of layout, this is probably the best because it allows the engine to be mounted lower (with a corresponding lowering of the center of gravity) as well as a longitudinally. (which for front driven vehicles allows for equal length driveshafts.)

 

[Kntx]

V type engines can be just as balanced as L type. Most V6's arn't because they are based off V8's (90 degree angle between the banks). L4s are not inherently balanced and require counter weights. L6's are, As are V6's with a 60 degree angle between the banks (Nissan VQ).