Possibly a bit OT or NT....

I am not very educated about engines. I know the basics of how one works, but that's it. Anyways...

Take the current MINI engine. Now double the number of cylinders, but make them half as large. So now you have 8, but they are smaller so they fit in the same space.

Compare that engine to the current engine. What effect, if any, would take place?

 

you would not be able to just divide the size of the bore in half and then multiply by 2. it just won't work. you would need a crazy design for the crank to work... anyways it won't work sorry!

were you asking just to see what would happen if you had a small bore 8 cyl. engine???

 

The purpose of an internal combustion engine is to convert chemical energy (gasoline) to heat energy (combustion) and then to mechanical energy (turning the crank shaft).

Because the heat energy is produced by controlled explosions in the cylinders, the mechanical energy comes in pulses as each cylinder goes through its cycle (4 of them) of intake, compression, ignition and exhaust. These pulses are noticed as vibration or roughness. The fewer cylinders an engine has, the rougher it will feel as the individual pulses of energy will occur at greater intervals. Therefore, if all other things are equal (engine displacement in your question), a 4-cylinder engine will feel (and sound) rougher than an 8-cylinder will. Also, there may be an increase in mechanical energy due to having twice the number of inputs (pulses) per revolution of the crankshaft; but probably not since the displacement of each cylinder is 1/2 the size of the 4-cylinder engine and so the amount of gas (chemical energy) used is the same in both engines.

This is (of course) theoretical and there would probably be more energy loss in the 8-cylinder engine from increased friction (more moving parts) and the effect of reversing the direction of the reciprocating parts (pistons, valves, etc.)

So... short answer - a different exhaust note and smoother running. I am not an automotive engineer, so take the answer with that in mind.

 

never heard of a 1.6l V8.

Doubt it would work. Whats the smallest V8 out there?

289 Ford? (just short of 5l)???

 

Chevy had a 262 and a 265cid small block.

 

Still a far cry from 1.6l V8 ... thats like a 4.5l

 

The 289 is not close to the smallest. How about the 260 Ford, the215 al. Olds from the early 60's (latter used in BL and Roots cars and Morgans) If you want small try a 5.65 cu. in. supercharged v8. Chec it out at http://www.topspeed.com/cars/car-new...e-ar10379.html

There are many smaller ones tha the 289.

Motor on

 

Figure Indy cars and F1 are running (or were) V8s in the 3.5 to 3.0 range. Granted they are also running 10k to 19k rpms.

But as far as a very small V8 goes, it just would not work. There is a line between function and friction.

 

Actually, F1 racing engines in the early to mid 60's were 1.5l and were mostly V8 configurations. The Lotus 25 was powered by a Coventry-Climax V8 of 1500cc displacement and when installed in Colin chapman's most perfect (IMHO) chassis it won the F1 World Championship in 1962!

There is no physical reason that V8 engines have to be as big as we 'Mericans are used to seeing them, but it would be pointless to try for "small" when the inherent balance and smoothness of a V8 will allow for nearly obscene numbers of cc's of hydrocarbons beng burnt (incompletely) and then spewed into the atmosphere!

Engine power is mostly a function of the conversion of chemical energy to mechanical energy (see my earlier post on this). Therefore, there are 2 basic paths automotive engineers can follow to increase H.P. at the flywheel: 1. burn more gas (the classic American approach) or 2. burn the gas more efficiently (the rest of the world's approach since at least the 70s). The goal is the same - convert as many BTUs as possible into BHPs (Brake Horse Power). It's all in the combustion of gasoline.

 

no one in their right mind would do a 1.6l v8.

sure, you could probably rev it to 12krpm, but it would make no torque. if you have seen a set of 1.6l pistons, you you will know what i mean.

it would be like a giant RC car engine. the pisons would be an inch and a half around, and you would probably want to cut the stroke in half also.

Whats all this talk about small for?

theres still no replacement for displacement.



^---Lawman Boss 429

 

What were the F1 engines when they were turboed 1.5 putting out 1000 hp in qualifing trim?

 

What he said ...

There ain't no substitute for cubic inches ...

all those wussie I4s needing SC or Turbo

 

Mazda used to have a 1.8l V6 - smallest production V6. Given that it's out of production, I'd call it a failed experiment.
In NA form, size = power, #cylinders = smoothness

 

Not only did the Coventry-Climax 1500cc engine (the FWMV) power Lotus to a world championship, but it also powered the Cooper T51-Climax in Formula Junior (wow! I invoked the hallowed name of Cooper! And yes, the same Cooper our cars are named for). And those engines were all "normally" aspirated. There's nothing wimpy about small displacement when it is accompanied by smart engineering.

 

GM also has 260c.i.d. V8's... or 4.3Liters for you metrically-minded folks. One interesting tidbit is that GM also makes 4.3 V6's. If you do the math, you'll find that the cylinder volumes are the same as that of a 350 V8. that's because they took a small block and cut off two cylinders - wallah - the 4.3 V6!

 

Basically, I guess. Getting a bit techincal on me there though. I figured smoothness would be a result of more pistons. When I thought of it I imagined a sine wave. With more pistons you have a higher frequency. But I wasn't sure what would happen with power, torque or anything else.


Displacement and cubic inches.... Ok, so displacement is the total volume of the air/fuel mixture. So by making the pistons concave, or increasing stroke length (stroker engine?), you increase the displacement. Right? I assume making the cylinders a bit larger in diameter (boring over?) has the same affect.

Makes sense. More air/fuel, the greater the bang and power and so on. But what if you made the pistons convex to compress the air/fuel tighter while using the same amount of air/fuel?

Edit:
I just thought about that a bit and realized that this is basically what the supercharger does.

 

I could imagine a short strove high reving small V8 (1.6 for arguement sake) being an excellent engine in a Locost kit, however the $$$ to desgin such a thing would rapidly turn it into a Highcost kit car.

 

Can you spell .... HEMI?

 

Exactly........no substitute for engineering. Cubic Inches are over rated....

 

There are a couple of 2.8ltr V8's created from Hayabusa 1.3lts i4's running.



They push out 375hp at 10,000rpm, normally aspirated....

Take a look at http://dpcars.net and check out the atom section

 

With the right technology, it would be great! A light, high strung monster. But if you run it on pump gas, you would need a good amount of turbo. NA, you would need a lot of nitrous, or run it on race fuel...could be fun though. The F1 engines are rediculous. Insanely small, and spinning 20K rpm. Although...for the cost of an engine like that, you could probably buy a few MINIs.

http://www.formula1.com/insight/tech...fo/11/467.html

 

While we're talking about F1s...there needs to be an unlimited F1 class...with no limitations. Let's see what happens when they can liquid cool breaks, add traction control...etc. It would be interesting to see how fast they could go.

 

Until half the field dies in the first race.

 

So, instead of VTEC's, could we put this V8 in a classic mini? oooh!!

 

Assuming you can find a gearbox in your price-range - it would not be a cheap option, but it would utterly rock !