What does the V in an engine specification stand for?

[Tiamat]

Originally posted by: PottedMeat
valves

how do you get fuel + air and exhaust in and out of the cylinders - valves

lol up until this time I thought it was Volts and never understood why cars had 16 volt or 24 volts. Now, makes so much more sense as valves!

 

[TitanDiddly]

Originally posted by: spidey07

Originally posted by: Truenofan
yeah and there also v6/v8's(Ferrari, lambo's) that have 5 valves.

I thought volvo was big on 5 valves per cylinder?

Or maybe they use a lot of 5 cylinder engines. Can't recall.

My engine has 3 valves per cylinder with variable valve timing. This allows a strong/flat torque curve, with just a small HP increase once the vtec kicks in yo.

Volvo does use some 5-cyl engines.

I used to own a Mercedes diesel with a 5-cylinder.

 

[imported_Truenofan]

VTAK YO! i have something similar to that on my engine, under normal driving, its 4 intake ports, and 4 exhaust ports, when i floor it and go above say, 3/3.5k rpms it opens up to six ports and gives a little more peak power.


edit: removed stupidness on my behalf.

 

[franksta]

Originally posted by: cardiac


An oddball is the Ford 6.8 liter V-10 found in the F-250/F-350 truck line. It has 3 valves per cylinder....


Bob

The 5.4L in the F-150 and the 4.6L in the Mustang are both 24 valve motors.

 

[Demon-Xanth]

If you want something that'll really blow your mind, look up how a two cycle engine works. A piston engine w/o valves.

 

[spidey07]

Originally posted by: Demon-Xanth
If you want something that'll really blow your mind, look up how a two cycle engine works. A piston engine w/o valves.

Meh, much easier and simpler design if you ask me.

It's so simple it's beautiful actually. Air, fuel, fire, compression = explosion.

 

[Harabec]

I'd like to point out something interesting.
Yamaha came out with their Genesis engine back in the 80's (in the FZ750). A then-high-tech Inline-4 with 5 valves per cylinder.
They stayed with that configuration on their higher capacity I4's for about 20 years until recently.
The new YZF-R1 has 16 valves - and it is more powerful than the previous generation R1.

BTW, the latest supersports are nearing 1:13 CR, with the ZX-6R having a 1:13.9 CR!

 

[jagec]

Originally posted by: spidey07

Originally posted by: Demon-Xanth
If you want something that'll really blow your mind, look up how a two cycle engine works. A piston engine w/o valves.

Meh, much easier and simpler design if you ask me.

It's so simple it's beautiful actually. Air, fuel, fire, compression = explosion.

Except that you throw away a decent bit of your power and a decent bit of your fuel out the exhaust, and you don't do a good job of getting all the exhaust out of your mix before the next power stroke. Easier and simpler, yeah, elegant, sure, but the 4-stroke is a lot better once you get to any reasonable size.

 

[SlicedBread27]

Originally posted by: Demon-Xanth
3 valves is a compromise between complexity and cost. Since it's easier to get air out than in.

Correct me if I'm wrong, but I think 3 valves lets you fit 2 spark plugs per cylinder which can improve fuel efficiency as well. I'm pretty sure MB stuck with 3 valves/cylinder on a lot of their engines for this reason.

 

[jagec]

Originally posted by: SlicedBread27

Originally posted by: Demon-Xanth
3 valves is a compromise between complexity and cost. Since it's easier to get air out than in.

Correct me if I'm wrong, but I think 3 valves lets you fit 2 spark plugs per cylinder which can improve fuel efficiency as well. I'm pretty sure MB stuck with 3 valves/cylinder on a lot of their engines for this reason.

My motorcycle has 4 valves and 2 spark plugs per cylinder.

 

[AMCRambler]

Don't the Cadillac Northstar engines have 4 valves per cylinder? Pretty sure I remember reading they had 32 valves.

 

[DivideBYZero]

Originally posted by: jagec

Originally posted by: SlicedBread27

Originally posted by: Demon-Xanth
3 valves is a compromise between complexity and cost. Since it's easier to get air out than in.

Correct me if I'm wrong, but I think 3 valves lets you fit 2 spark plugs per cylinder which can improve fuel efficiency as well. I'm pretty sure MB stuck with 3 valves/cylinder on a lot of their engines for this reason.

My motorcycle has 4 valves and 2 spark plugs per cylinder.

The Alfa TwinSpark motors are 4 valve, 2 plug config, too.