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The question is... ----> http://www.skylinesa...-rotaries-suck/ :ph34r:

holy f**kbeans, just found that thread, mind = blown, only read 8 pages of it, but most of the story has been told, i assume the next 50 pages is just flame throwing

They do 0-100mph in around 0.7 seconds.

They are 30ft long and by the time the back wheels get to where the front wheels started from they are doing 100kph.

It's kinda like trying to comprehend the size of the universe. My poor brain can't compute the awesomeness.

That is the top fuel WORLD record 1/4 of 4.4 seconds which equals to 4.3gs however most dragsters will not be achieving such times.

Back to the main point, no road car is ever going to do 0 to 100kph in under 1 second. Nor is there any point, such acceleration would provide g forces most people cant handle.

Nor is the car going to do 600kph.

99a6015b6a230860c9b1517b238e5de9.png

Drag equation. (assumptions, 1.8x1.6 meter front of the car. 0.25 coefficient of drag [low], same car)

Drag forces at 600kph.

((1.225 * (166.7^2))/2) * 0.25 * 2.88 = 12,254 Newtons of force required.

Drag forces at 400kph.

((1.225 * (111.1^2))/2) * 0.25 * 2.88 = 5,443 Newtons of force required.

So that is a 125% increase in drag forces whilst only increasing speed by 50%.

I highly doubt they ll crack the 500kph barrier.

Edited by Peter89

Well, with 2000Kw's it'd probably have the power to hit 500 if its similar in size shape and drag to the veyron that can do 400 with ~1000hp. 2000kw's out of the proposed engine isn't that unimaginable, though reliability would be an issue. I think the biggest problem would be making sure that at 500km.h the car just doesn't flip out and explode.

Well, with 2000Kw's it'd probably have the power to hit 500 if its similar in size shape and drag to the veyron that can do 400 with ~1000hp. 2000kw's out of the proposed engine isn't that unimaginable, though reliability would be an issue. I think the biggest problem would be making sure that at 500km.h the car just doesn't flip out and explode.

350hp out of a 650cc single cylinder? Yeah, I don't think so. No amount of forced induction and weird and wonderful fuel is going to hit that. Not to mention 440nm of twist.

You would need the equivalent valve area of a small block V8 in each cylinder to achieve that kind of power.

Edited by Cowboy1600

350hp out of a 650cc single cylinder? Yeah, I don't think so. No amount of forced induction and weird and wonderful fuel is going to hit that. Not to mention 440nm of twist.

You would need the equivalent valve area of a small block V8 in each cylinder to achieve that kind of power.

In the late 80s with F1 when turbos were allowed, they were making up to 1400hp on 1.5litre engine in qualifying. Flash boost pressure readings of 5.5 bar however it is to be noted that they weren't running just petrol but with other chemicals like toluene. Thus 350hp out of 650cc isn't impossible at all. Also remember this was the late 80s, a lot has change since then.

5.2 litre rotary could easily make 2000kw however the fuel to run such a car would be insane. it wouldn't get very far. A 5.2 litre rotary is practically a 15.6 litre 4 stroke engine, add to that high boost pressures and you ll get insane power levels.

Reliability and weight are a totally different matter though.

Edited by Peter89

I was basing that off some quad rotor 2.6 engine (eg half the specified engine for this supercar) that made 1300hp on a flywheel dyno. I mean sure flames were shooting out of the manifold, hence the reliability issues, but it made that power...

Oops, I forgot it's a rotary. That certainly changes the equation, but I think any 5.2L motor is always going to struggle to put out nearly 3000hp for a decent length of time.

In the late 80s with F1 when turbos were allowed, they were making up to 1400hp on 1.5litre engine in qualifying. Flash boost pressure readings of 5.5 bar however it is to be noted that they weren't running just petrol but with other chemicals like toluene. Thus 350hp out of 650cc isn't impossible at all. Also remember this was the late 80s, a lot has change since then.

5.2 litre rotary could easily make 2000kw however the fuel to run such a car would be insane. it wouldn't get very far. A 5.2 litre rotary is practically a 15.6 litre 4 stroke engine, add to that high boost pressures and you ll get insane power levels.

Reliability and weight are a totally different matter though.

Crazy sh** the old F1 cars. Reliability, cost, lives, exploding cars, all a mere formality just so long as their driver was on poll....

Crazy sh** the old F1 cars. Reliability, cost, lives, exploding cars, all a mere formality just so long as their driver was on poll....

and some of the best F1 racing. The lack of safety in the car wasn't due to the engines, it was due to the poor design of the underbody and chassis.

Also, it was the 80s. 30 years of engine development since. I am sure they could produce even more power today with even better reliability, especially with todays computers.

Edited by Peter89

and some of the best F1 racing. The lack of safety in the car wasn't due to the engines, it was due to the poor design of the underbody and chassis.

Also, it was the 80s. 30 years of engine development since. I am sure they could produce even more power today with even better reliability, especially with todays computers.

Interesting idea. 1400bhp from 1.5, 30 years ago, imagine what could be created now...

probably 1500hp. Engines have come a long way, but not all the tech is directed to pure power. not to mention there's a set limit to what you can physically get out of air and fuel forced into a combustion chamber.

probably 1500hp. Engines have come a long way, but not all the tech is directed to pure power. not to mention there's a set limit to what you can physically get out of air and fuel forced into a combustion chamber.

That's what people need to realise.

You are limited by valve surface area. I'd say 1400hp out of 1.5L is about the limit. Although one big advance over the past 15 years has been in metallurgy which has allowed bigger bores and smaller strokes. Look at slipper pistons, especially as now used in motorbikes. That said, I'd say efficiency rather than outright power is where the big advances have lead us.

My point more was that over the last 20 years we've been mainly focusing on changing combustion to reduce the amount of bad shit, like oxides of nitrogen, that are produced during combustion, which doesn't really add anything to the power produced by the engine as such.

I mean any workship can take a rb26 upto 4-500kw with the right boltons, but that doesn't mean nissan can (or could) due to the fact that it blows the emissions testing out of the window.

edit: at least that's my impression anyway. with regards to the motorcycle engines, guy next door's kid has one of the new ones, i think they're rebuilding it after less than a year of semi regular weekend only use...

Edited by sneakey pete
My point more was that over the last 20 years we've been mainly focusing on changing combustion to reduce the amount of bad shit, like oxides of nitrogen, that are produced during combustion, which doesn't really add anything to the power produced by the engine as such.

Government-regulated attention in emissions is there, but that doesn't mean the engines aren't producing more power than they were for a given displacement or per unit of fuel. A big change has been thanks to the improvement in electronics, both in terms of performance and cost, which has let motors react more quickly to a greater amount of input data. That's allowed them to tune engines closer to the limit without compromising reliability.

Aside from emissions its managed to both reduce fuel consumption of the engine itself and increase power (heavier chassis offsetting those gains notwithstanding since we're talking about engine tech). If you think about the last time the automotive world went on a big ecomentalist kick, it choked every engine that came out. These days power outputs relative to displacement or fuel consumption has still increased even though emissions regs are getting tighter.

I mean any workship can take a rb26 upto 4-500kw with the right boltons, but that doesn't mean nissan can (or could) due to the fact that it blows the emissions testing out of the window.

Not with an RB block, which is 20+ years old from an engineering standpoint, but it they were to engineer a modern "halo model" turbocharged 2.6L engine block today that complied with current emissions regulations it would still make more power, and be less laggy, than what an RB26DETT actually made (since we know the 280ps figure was basically porkies). It probably wouldn't hit 400kW but it would still make a fair amount of power.

If you have a look at the VR38DETT, it makes a conservative 360kW, modern engine tech is not looking too bad. If we linearly scale up via displacement, and use a 320PS power figure for the RB26DETT instead of 280PS, then 3.8/2.6 * 320 = 470PS. The first-gen VR38 made 485PS, and that figure is just going to increase. Of course, we know that power doesn't increase linearly with displacement and so the true power gain due to developments in powerplant technology is more than just that small fraction.

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