Any Mechanically Minded here...Radial Engines question..

Sponsored Links
AdamW said:
Any idea why radials always had an odd-number of cylinders?

Or why inline engines always have an even-number (apart from those rather uncommon 3- and 5-cylinder engines)?
something to do with vibration and opposing forces?the bmw straight 6's are super smooth but some v8's can seem a bit lumpy.
 
ohmygodwhathaveyoudone said:
Or why inline engines always have an even-number (apart from those rather uncommon 3- and 5-cylinder engines)?
It would be more accurate and concise to say that inline engines don't always have an even number of cylinders.
 
Sponsored Links
Apologies for posting a topic then seeming to disapear..had a busy time at work followed by a couplke of public hostelry sessions.. :LOL:

Anyway, great feedback Guys, thanks. From what I understand the Rotary engines that Mazda use do produce a lot of power for their size, but in relation to similarly powerful inline a V engines they drink fuel at an amazing rate..as well as oil..

I was thinking that perhaps you could produce a small radial engine, sa total of 2 ltr, and lay the cylinders flat with the rotating shaft in the middle, this could then be geared onto a shaft placed at 90 degrees to the cylinders to tranfer the power, via a gear box, to the drive wheels.

I'll have a hunt about as I seem to remember that the FW190 (Focke-Wolf) had an engine of similar capacity to the Merlin, but drank less fuel and coolant in the process, which is why it's range was higher than the Spits and Hurricanes.
 
Softus said:
It would be more accurate and concise to say that inline engines don't always have an even number of cylinders.

Even better if I had written "inline engines seldom have an odd number of cylinders". ;)

Or if I had wanted to be an engineer about it: "All inline engines should have an even number of cylinders". :p

Do you have an answer to the question by any chance?

something to do with vibration and opposing forces?the bmw straight 6's are super smooth but some v8's can seem a bit lumpy.

Well, that was the first thing I thought of. But, all you do is space them evenly. A radial with 6 cylinders should be smoother than one with 5, surely?

And with a straight it's very easy: instead of having 4 cylinders with 90 degrees between phase, have 5 cylinders with 72 degrees. Smoother.

It just seems to me that at some point people arbitrarily decided that car engines should have an even number of cylinders.
 
Back
Top