V-4

[riff_raff]

shrek,

There are millions of V4 sportbike engines.

And, of course, there's also the V5's:

[CMSMJ1]

I wouldn't say there were millions - only Honda seem to persist with them for road bikes..

Mine is an NC30 - revs to 15,2000 rpm and is lovely. A real little diamond.

For cars the packaging is not so much of an issue and IL4 is the ideal solution.

My step dad had a Lancia Fulvia with a V4 - that was a nice motor..

edit for spelling..

[ISLAMATRON]

ahhhh the beauties of the rotary

[010010011010]

Mine is an NC30 - revs to 15,2000 rpm and is lovely. A real little diamond.

15,2000 rpm! Wow

would there be anybenifits of making a 1200cc v8 out of two 600ccc straight 4's?

or would a normal straight 4 1200cc engine be more powerful

[flynfrog]

ahhhh the beauties of the rotary

the fuel consumption, or the egts. or the emissions or the rebuild times?

[tok-tokkie]

Mine is an NC30 - revs to 15,2000 rpm and is lovely. A real little diamond.

15,2000 rpm! Wow

would there be anybenifits of making a 1200cc v8 out of two 600ccc straight 4's?

or would a normal straight 4 1200cc engine be more powerful

A V8 has been made in Australia for motorcycles from straight 4s
Drysdale http://home.mira.net/~iwd/

I think there is another one also in Australia

[modbaraban]

Behold the power... (all there is of it) of the rear-engined V4 ZAZ 965 "humpy" (the Fiat 500-like) and 968 / 968M (the NSU-like) of 1960-70s.

http://en.wikipedia.org/wiki/Zaporozhets

[youtube]http://www.youtube.com/watch?v=k0SEilw38PU[/youtube] [youtube]http://www.youtube.com/watch?v=spSBdz076ko[/youtube]

made in Ukraine

[010010011010]

A V8 has been made in Australia for motorcycles from straight 4s
Drysdale http://home.mira.net/~iwd/

I think there is another one also in Australia

Cool

any idea of power or torque figures for them?

[ISLAMATRON]

ahhhh the beauties of the rotary

the fuel consumption, or the egts. or the emissions or the rebuild times?

none of those(except for maybe emissions) is ever a problem for me in any of my rotary build & tunes... but this is not the thread for that discussion

[TauToadmiester]

Huge topic but here are some non mentioned aspects:

F1 Engine design is all about packaging, frictional losses, vibrations, center of gravity and of course power and economy (especially in 2010), etc.

Much of F1/ultra performance engines are about frictional losses via metal scraping (piston rings etc) and turning (camshafts, cranks) and pumping losses via oil circulation and presence (dry sump, less losses) and obviously piston air/fuel flow. This is attacked by 1 ring pistons, bearing types and surface tech, and lubrication technology, (many more ways) etc. Frictional losses can exceed the increase of HP with an increase of RPM's, as well as they turn rotational energy into heat!

Engine design also must consider the primary and secondary vibrations and how the engine is mounted and what is mounted/connected to the engine.

Primary vibration is the 'mass' balance vibrations, secondary vibrations are the power pulse vibrations, further vibrations are ancillaries (pumps, chains, etc) also contributing to the total vibrations. These are important because of solid chassis mountings, vibrations can damage the block or ancillaries systems,etc.

ALL the engines in F1, at least since the turbo days, use a 180 degree crank which means a V-10 is 2 I-5 engines with a shared crank, a V-8 is 2 I-4's with a shared crank, the V-12s 2 I-6's, etc.

Nascar/road cars use a 90 degree crank and 90 degree bank angle which allows perfect primary balance but the power pulses (secondary vibrations) (piston firing) are very uneven (720/8 degrees), as you can easily hear, and the uneven power pulses are damped easily by the engine mounts since the primary balance is 'perfect'.

Whereas the F1 180 degree crank uses the V angle (crank counters) to minimize the vibrations (not perfect but not bad) for the chassis and transmission's sake, which I believe is about 72 degrees these days, (remember the 120 degree V-10 Renaults driven by Button that Flavio finally canned). Thus the F1 has piston firing more evenly spread across the 720 degrees.

The reason for F1 using 180 degree cranks is the exhaust scavaging (previously mentioned) (both positive and negative pulses to assist in fresh gas inhalation/mix or exhale of spent gases via the other pistons) is simpler. The 180 degree crank gives the engine that F1 harmonious howl sound (evenly spaced piston firing).

The reason for the intense amount of exhaust 'wiggling' and twisting is to achieve equal power (and all the above sympathetic scavenging/pulsing help) to all pistons and simply packaging (it must fit from in here!).

It is this exhaust tuning, lower friction/pumping losses, all the cylinder head/piston tech, etc that gives the F1 engine the ability to rev so much higher than say Nascar.

But even though Nascar and F1 engines make about the same HP, the displacement is much different, there is much more dynamic mass in the Nascar, thus a Nascar engine could never (probably) spin to even 15,000, let alone to the 21,000 rpm of F1 (2006) (or close to this), simple physics not an insult to Nascar.


PS: It took F1 many years to spin to 20,000 rpm and probably $$ billions total!

Just 1 man's opinion! Sorry if I mislead or outright lie!

(Don't you wish a politician would say/admit that!!)

[GrndLkNatv]

shrek,

There are millions of V4 sportbike engines.

And, of course, there's also the V5's:

Heck they make a ton of them in the two stroke version, OMC/Johnson/Evinrude/Yamaha and even Honda does in a 4 stroke version, all for boats.

http://www.boatmotors.com/motorparts/in ... 698&flag=2

[Terrible3]

Why hasn't anybody built a V-4 and why

All Subarus rally engines are flat-4
Thats a V at 180°

A flat 4 and a 180* v 4 are completely different. The crank shaft design being the main difference.

[DaveKillens]

But to answer the question an I4 is a much better configuration for a 4 cyl engine. Its much less complex and cheaper to build. Its most of the time easier to package.

I believe that is the correct answer. Let's face it, almost every automotive 4 cylinder engine is designed for small cars or light use. You're not going to see one in a Lincoln, or Bugatti. So since the design of the 4 cylinder engine is to be optimized for a small car, it will also have to be as cheap as possible.
If you don't believe me, just stand on the side of any street and count the number of small, cheap, 4 cylinder cars that go by.

And if you are going to build an engine as cheaply as possible, an inline engine is cheaper than a V configuration.

[xpensive]

A flat 4 and a 180* v 4 are completely different. The crank shaft design being the main difference.

Can someone please xplain the above, was a Ferrari "flat-12" of the 70s not just a 180 degree V-12?

[timbo]

A flat 4 and a 180* v 4 are completely different. The crank shaft design being the main difference.

Can someone please xplain the above, was a Ferrari "flat-12" of the 70s not just a 180 degree V-12?

Apparently it was Flat-V engines.