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asking why a str8 6 is better than a v6 is a valid question imo.

I have read auto books that refer to the V as "VEE". Basically it depicts the orientation / configuration of the engine - V shaped and equal cylinders on each side v6 = 3+3, v8 = 4+4, v10 = 5+5, v12 etc...

I dont know how or why the straight configuration is intrinsically better though..[or if it is]...

red900...i suppose u're rite in that instance, but i have seen videos with pistons 1,3,4,6 all at tdc together, specifically, a supra's six. so if u say 1 is on compression n 6 is on exhaust, i assume that 3 and 4 would be the same?

so basically, you get 2 cylinders on compression n 2 on exhaust am i right?? i'm confused...

if pistons 1 3 4 and 6 are at TDC all together it's because something in the motor has gone horribly horribly wrong :(

generally, firing order on an inline six is 1, 5, 3, 6, 2, 4, but remebering that they are paired together, so that 1 and 6 are at the same position in the bore as each other, 2 and 5, 3 and 4 so on. it's the camshaft that determines whether or not each piston at TDC (Top dead centre, or the highest point in the bore) is actually at it's compression stroke or exhgaust stroke.

remember folks, it's Compression, Ignition, Combustion, Exhaust (Or Suck, Squeeze, Bang, Blow if thats easier to remember :D)

The V means the motor is in a V shape, with 3 pistons on each side. this makes it easier to fit in small engine bays, but the downside is they vibrate and therefore engine harmonics is poor. This can be compensated with a balance shaft or a bloody big harmonic balancer on the front to soak up the vibration. it also takes a lot more machining to make and can be expensive.

an inline motor, all pistons are in a line one after the other. an inline motor is very bulky and needs a long engine bay. but vibration is minimal, except with big revs, when the crank can actually start to flop around like a skipping rope. again a harmonic balancer is used if the motor is prone to this. (modern motors dont usually have this problem anymore, it's mainly old motors with big crank journal spacing that did this)

Ok, so we all agree that the inline 6 is a very well balanced sweet sounding motor.

But don't ya just love the sound of a V8 ??? I love the growl (and the sound of the V8..........let see who gets that ?)

Why does the V8 sound (to me) better then an inline 6 ?

Don't get me wrong , when my turbo spools up and that R33 induction noise is happening, I get a half wood - But it goes to 3/4 wood when I hear a sweet V8 (like a Soarer that has been worked a bit - nice)

PS - I'd still beat them all off the line but........

Guest RICE ROCKET

Hmmmmm I have no doubt that what your all saying about the str8 6 is better but I have seen some nice moving V6 Twin turbos, and mummu do they move. What do you think the 300ZX runs? 3 litre quad cam 24 valve EFI V6 Twin-turbo. Can anyone honstly tell me that there is something in this puppy that isnt better than a straight six. An RB26DETT yes but a 2JZGTE.....well letz not go there.

Well, its a bit general to say a straight 6 is "better", it may have more inherant smoothness, but that can certainly be designed in or out of an engine too.

The ultimate power/torque/rev trade off is mostly determined by the bore/stroke and head design.

A long stroke straight 6 won't rev higher than a short stroke V6.

The reason that almost every manufacturer uses v6 is that the engine is so much sorter - so better handling/packaging in the car. Long engine, hanging over front wheels = understeer prone.

Originally posted by RICE ROCKET

Hmmmmm I have no doubt that what your all saying about the str8 6 is better but I have seen some nice moving V6 Twin turbos, and mummu do they move. What do you think the 300ZX runs? 3 litre quad cam 24 valve EFI V6 Twin-turbo. Can anyone honstly tell me that there is something in this puppy that isnt better than a straight six. An RB26DETT yes but a 2JZGTE.....well letz not go there.

The 300ZX uses a V engine to get the nose lower and the engine bay shorter, to help improve handling and aerodynamics. This is a high powered high speed sports car remember, not a grand tourer.

It also has 3 litres to play with, to give it a slight edge over the RB engines in the power stakes. If it were only 2.5 or 2.6L, the RB engine would crap all over it in power and revability. It would still have a slight advantage in the weight and size distribution though.

Edit: Also for some reason, V engine designs seem to be easier to get cleaner emissions out of. Holden's ECOTEC is a prime example, when compared to Ford's inline 6. Also, the next generation of Skylines is going to the V engine design, primarily due to emissions.

A couple of questions thats slightly off topic,

W12 n W16 engines, are there any for sale in Australia?Has anyone here driven them? I've read on the VW web page that the exhaust noise generated is absolutely insane....

and...

Has any car company made a V4? And would there be any savings in making one?

V4's exist in motorcycles, mostly for weight distribution and balance. They're sort of a compromise between an inline 4 (front-heavy and wide) and a twin (narrow and good weight balance, but less power and revvability). There isn't much point to having them in cars because inline or boxer 4's are compact enough to fit in a square enough configuration anyway, in most small cars. A boxer can probably do everything a V can but with better balance characteristics.

Btw, V and boxer engines are generally more expensive to make than inline engines, because they have 2 cylinder heads.

I think...and correct me if I'm wrong..... The "V" style also has a lot to do with the "Torque" of and engine. If you understand torque then you will see why the "V" shape would aid torque. Inline engine's have good balance (as we know) therefore allowing them to rev higher.

But...

Then we get in to bore size and stroke, and then it gets all weird again.

The RB engine was designed with one thing in mind.... Rev's. The compromise was low torque, hence the addition of the turbo (or 2). Those who drive GTS-T's will realise that the turbo was placed there to aid Torque. hence why the spool is early and aids the most between 3 and 5,000 rpm. At the top of the rev band the turbo flow match (i think). that also show's why the turbo's fail at high boost, they wern't designed for that much heat and flow.

I could be wrong in a lot of what i've said here, i'm going off thing's I've learn't over time about car's. The best way to understand would be to talk to your local Mechanic. I'm sure over a Beer at the pub, they'll tell ya all aobut it.

Cheers

Loz

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