I was thinking if you think of the v8 engine as 4 v twins. It fires 2-1 then 8 skip 7 then 4-3 then 6-5 then 7. 3 of the v twins fire the same. Which cylinders is it that they switch when they change the firing order?
Railguy

 

4/7 and 3/2, it supposedly aids the fuel charge on the longer manifold runners and relieves some crank stress at higher rpms.

 

If you figure it takes 2 revs for all 8 cylinders to fire that's 720 degrees. Devide that by 8 is 90. So in the firing order are all cylinders exactly 90 degrees apart or does it vary.
Railguy

 

I guess it would have to be 90 degrees as the distributor cap is evenly spaced. Railguy

 

It is a 90 degree block, so, yes, every 90' of crank rotation there is a power pulse.
Four per turn
Eight per full two-turn cycle.

 

V8, Boxer 8 or inline 8, they all have 90 degrees between firing.
The Buick V6 of the '60s and early '70s had an odd sound and very lumpy idle because the cylinders were in two banks at 90 degrees and needed a 60 (or 120) degree angle for even firing. But the engine was based on a V8 design.
Further development with a redesigned crankshaft evened out the firing pulses, and the engine was a very sturdy, robust unit, improved still further by the addition of a balance shaft around 1992.

Four, six or eight cylinders have been the mainstay of passenger car engines for many years, Six and eight cylinders made for a smooth running engine, four was acceptable for the smaller engines of European cars. Citroen offered a twin in their quirky 2CV model, Daihatsu a three in the Charade in the '70s, A few cars in Europe have three cylinder engines as an option for bargain basement models. VW made a five cylinder engine, first available in some Audis. Five cylinder diesels are nothing new, but this was claimed to be the first gasoline unit for general sale.
The Dodge Viper V10 was possibly also a first. V12s have been around for decades, excelling for smoothness rather than raw power, V16s last saw any kind of volume production pre WW2 I believe.

Roger.

 

nice synopsis there Rustman.

I once had a Saab 93 (?) three cylinder TWO STROKE car engine

That's a sloppy bucket of weird engineering right there.

I have had the 3-banger 2-stroke inline motorcycle also.

 

A few eastern European cars had 2 stroke engines as well, cheap and simple engines for low paid working proles I suppose. I believe quite a few cars had 2 stroke power between the world wars, and some post war "Bubble Cars" from Germany might also have had them.
But emission regulations have consigned them to history now.

Roger.

 

I WAS going to say that some outboards are still two stroke, but then I looked at Mercury's website, and there are none, so now I am not sure.

 

Maybe chainsaws or weed whackers are available with 2 stroke engines. how about snowmobiles?.
2 stroke lends itself to engines that need to work when tilted over or even upside down, such as a chainsaw.

I think the Tuk-Tuks in India have 2 stroke engines, I'm not sure if motorcycles with 2 strokes are still on sale in the UK, our emission regulations are more lax for two wheel vehicles.

Roger.

 

Since this dissolved into a 2 stroke discussion, nothin sounds off like the GMC 71 series diesel 2-strokes. I believe they went from 2 cylinders up to 12, including a 3 cylinder version.

 

Detroit diesels are 2 strokes.
Railguy

 

GMC/Detroit are the same engines. I heard they used the Detroit name so GMC engines would be accepted in other truck makers rigs.

 

The idea was to improve fuel milage through reducing engine friction. The cost was only one possible firing order. Only beginning with 4 cylinders were different firing orders possible. Because of this, the 3s run rougher.
The later Charades came with four-bangers. I now drive one of the smallest Daihatsus with a three-banger:

 

Trouble was they didn't really show any significant benefit over similar size and output fours. Possibly fractionally better mileage, but barely noticable.
My step daughter has a Daihatsu Sirion with a three cylinder engine. She bought it because it was a small car at the right price. She has mentioned that on longer trips the ragged engine beat gets annoying after a while.

Roger.

 

I bought mine in the Netherlands and drove it over a thousand kilometers home. I didn't find the engine annoying, throughout the entire trip. Rather, the harsh ride. Your step daughter's is the same basic engine still produced for Toyota and installed into small Peugeots and Citroens.
Her Sirion rolled off of the same production line with the Subaru Justy, unless it's the wagon pictured below, in case she has trouble finding parts or getting service.
Toyota bought out Daihatsu and then completely abandoned the brand in Europe, to the point where no loyalty to loyal customers would longer be recognized. At that point, if possible, I'm completely boycotting their products. Getting certain bits for mine is a nightmare. Direct shipment from Malaysia and Japan is either impractical or even impossible, in the case of Malaysian aftermarket, unless I visit them personally