Mazda RX8

So... no pistons. Didn't rotary engines suffer from horrendous wear at the tips? Whats changed?

I have a friend who bought one. He tells me that the improvement is a combination of better materials and lowering the pressure. I gather the worst offenders have always been turbos, and without that it isn't really a problem. The thing still guzzles gas like a Hummer though, they didn't fix that problem.

But damn it is a sexy ride...

Yeah, it looks nice and all and it handles like a dream. But the damn thing has no power. I test drove it and I was nowhere near as impressed as I was with the 350Z. It takes forever to get off the line where the Z jumps. IMO, I think the Z is all around better for your buck.

Well, the Z is sexy too.. can't go wrong there. For that mater, I love the lines on the G35 Sport Coupe (based off of the 350Z). It's a good time to be in the car market.

If you want something faster but not sexier, the Evo or STi are good choices too.

I'd agree with that, except the G35 is way over priced and has even less HP then the 8.

I totally agree with your ideas of the Evo and STi. Good choises for the speed... but they're so damn ugly...

Excluding the '02 WRX (in silver)!

thread hijacking here... but i got a ride in a EVO a couple of weekends back... and holy sh!t. It is absolutely amazing what they can do to an econobox like that with a bunch of racing parts and a turbo. You can feel how it just begs to be pushed and feels completely comfortable at the limit. It's a street legal racecar that thing. If i had to choose between an STi and an EVO purely based on performance i'd have a hell of a time deciding. The seats in the EVO are straight up racing Recaros and are way better than the WRX/STi's. Looks, on the other hand, would be an easy choice.

They made several changes to the new Renesis motor, their is a lining to help wear on the tips, and the exhaust & intake ports were moved to the side of the block to greatly improve emissions and mileage, but without turbos the tiny engine does not have any power until extremely high RPM, like 7500-8000, which makes it so slow. I would like to see one with turbos on it though.

An engine like that takes come getting used to (hi-reving). The Honda S2000 has/had the world record for the most hp per liter, but it also had a 9000rpm redline so you had to know to keep it up in the rev range to get any power. I assume the RX8 is the same. Somebody coming from a V6 or V8 won't be used to that immediate torque and will think an engine like this is underpowered.

I know the same is true for a turbo engine. My WRX was my first turbo car and it took me a few months to really know where the power band was and how to keep the car up there. Sometimes when I have a buddy drive my car, he'll wonder why it's slower for him. I just tell him that he'll need more time behind the wheel.

I heard a turbo RX8 is on the way (perhaps as a Mazdaspeed Edition), so maybe they've worked out those issues too. All engines are more advanced compared to 30 years ago, so I assume the same is true for the rotary engines.

I've driven a friend's S2000, and the powerband is unmistakeable. You get it above 6000rpm and the engine gives you a swift kick in the rear. Same thing on a Toyota Celica GT-S albeit with a much lower red-line, so the powerband is much more constrained. I test-drove an RX8 and it was much less clear how to get any power out of the thing. It makes much sound and fury as you rev it up, but it doesn't really feel any different than it does at lower RPMs. I nearly gave the poor dealer a heart attack while I was trying to push that damn car. "Was that sound the over-rev indicator?"

Not that its really compairable to the 8, Z, Evo, etc.... But I just glow whenever I sit down in my 2002 Mercedes Benz C230 Kompressor (Black). I like not having to wait for a turbo to kick in... the power is just there all the time. I look forward to getting my pully upgrade kit and supercharger tune-up package. This baby beast will be pushing about 325 HP at that point. *grunt* *grunt*

4 cylinder motorcycle engines make a huge amount of power the same way. Honda is one of the best. They have 600cc 4 cylinders developing over 120hp. The only way you can do that is to rev the crap out of them.

Since power is the *rate* of delivering work, smaller engines with less torque can still make a lot of power by working at high speeds.

I'm just starting to get into motorcycle racing and many experienced racers suggest starting on a V-twin bike like a Suzuki SV650 for exactly these reasons. The V-twin bike has less peak power, but the power delivery is more even and you don't need to keep the engine in such a narrow rpm band. The 4 cylinder machines are much, much more powerful, but you need to manage the RPMs much more carefully and keep them high at all times.

All engines are more advanced compared to 30 years ago, so I assume the same is true for the rotary engines.

Yeah, I suspect that relative to 4 stroke engines, rotary engines may still have a poor reliability rating, but as long as the engine lasts 100K miles without any major work...

Since power is the *rate* of delivering work, smaller engines with less torque can still make a lot of power by working at high speeds.

Another, even simpler way to think about it is that an engine is a device for converting gasoline into kinetic energy. The more gas you can consume, the more energy you're adding and the faster you'll go. So, the only question is how to make more gas get eaten. You can go for more engine displacement, more cylinders, injecting the gas more often (rotary, 2-stroke, higher RPM), more compression, more air to support the combustion of more gas (turbo, supercharger) and so forth.

Of course, that would say that a high-revving Honda S2000 with the 2.0 liter 4 cylinder engine and a lower revving Ford Mustang with the 4-odd liter V8 are roughly equivalent, modulo gearing and all that extra weight for the big V8 block, or the additional materials cost of keeping the Honda engine carefully balanced and machined so it doesn't self-destruct from the high piston velocities.

Hmm....

Same thing on a Toyota Celica GT-S albeit with a much lower red-line, so the powerband is much more constrained.

Anybody notice that Proton is finally bringing the Lotus Elise to the U.S. using the Toyota Celica GT-S/Yamaha-designed heads VVTLi engine? Sweet!

Another, even simpler way to think about it is that an engine is a device for converting gasoline into kinetic energy.

Isn't it converting gasoline and oxygen into kinetic energy?

So, for example, if you could get the engine to consume more oxygen, that would also increase its power. Hence turbochargers and such...

Yes the american elise

fully loaded with airbags, air con and lots of other junk you really don't need on a car. From what i heard it is coming around 950kg which is very heavy for an elise

So, for example, if you could get the engine to consume more oxygen, that would also increase its power. Hence turbochargers and such

Nah, the simplification of rate of gasoline consumption is better. For example, diesel engines run inherently lean to avoid overheating. They consume more oxygen, but dont combine it with a hydrocarbon to produce heat (power).

More fuel input + efficient combustion = more power All you need to know

Isn't it converting gasoline and oxygen into kinetic energy?

Turbochargers and such do add more oxygen to the engine, but but its not the extra oxygen thats adding the power. More oxygen in the combustion chamber means that you can add more fuel and its the increase in fuel which gives you power. Unless the air to fuel ratio is correct, the combustion wont happen properly or even at all. The cars computer uses the air flow sensor to determine how much oxygen is being sent to the engine and it compensates by adding the correct amount of fuel to keep the air fuel ratio correct.

Ahh, you're a purist! I can definitely appreciate that (I owned a U.S.-spec BMW factory-ordered with a cloth interior, no cruise control or sunroof, and full manual HVAC controls.), but surely you realize w/o airbags it's illegal on public roads and w/o A/C it's completely unsellable even in Alaska.

And I'll stop calling you "Surely."

Not here it ain't

but i am buying a 7 so i am going beyond purist into nutter camp

As they have no airbags, no ac, no electric windows, no central locking, no roof, cardboard doors, no wind up windows, no boot basically its 4 wheels engine gearbox and 2 seats

basically its 4 wheels engine gearbox and 2 seats


Two seats? Talk about overkill. And you call yourself a purist!

tanstaafl.

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Two seats? Talk about overkill. And you call yourself a purist!

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Yeah, totally! I mean, unless you're rally racing, you don't have a co-driver so a 2nd seat IS overkill!