mmarshall

Next planned reviews: 2009 Acura TL, 2009 Hyundai Genesis V8, 2009 Nissan Maxima

Threxx

My friend had a (I think) 2005 RX-8, 6-speed manual, fully loaded with the bose system, xenon lights, etc.

I just didn't care for it.

I think it'd be pretty fun around a track, but damn on the road it just sucked because you had almost no power on tap unless you revved the **** out of the engine, which felt like it was abusive and I guess it was because he needed a new engine at 42k miles. He ended up being FORCED to trade it in by the dealer because when the engine blew he was 5 days away from having to report to his new air force base on the other side of the country (Tennessee to Arizona... he's a fighter pilot in the USAF). He even showed the dealer his papers but they would NOT budge on the loaner car rules... they said we can give you a loaner car and have your engine done in 2 weeks but then you'll have to drive it back to Tennessee to drop it off and drive your RX8 out to Arizona.

I raced him in my GS400 and beat him by a good margin, then raced him again in my Audi A4 2.0t and it was pretty much dead even. Not good enough IMO considering his RX8 stickered almost the same as my A4 and was far less practical and comfortable and got practically half the gas mileage I did.

So he would have had to either drive cross country round trip twice, the second time in the middle of his assignment to his new AF base which could have had him AWOL, or buy a plane ticket to Arizona, fly back three weeks later, and then drive out there - still possibly AWOL and out the cost of a plane ticket and rental car in Arizona. They weren't willing to foot the bill on a single bit of it despite their known faulty engine leaving him in this situation.

He just got frustrated and moved on.

mmarshall

Yes, I emphasized both points in the review.....the lack of low-RPM torque and the questionable long-term engine durability.

If he was an air force fighter pilot, then why couldn't he fly his OWN fighter out to the new AZ base (Luke AFB, I assume), or, barring that, just hitch a ride on a military transport plane? If the USAF orders him there, it is their job to either give him a ride on a transport plane or cover the cost of the jet fuel for his fighter.

Threxx

He was in Memphis visiting his parents at the time. Fighter pilots can't just hop in 'their own personal jet' and fly wherever on a whim... it has to be a mission cleared by command, and they're never used for personal transportation.

It's true that they pay for moving expenses but they don't cover extras like "oh your car broke down 5 days before so we'll pay for you to do all this extra hopping around and give you the leave you need a couple weeks ago."

mmarshall

Of course. I understand that. I was a pilot myself. But I don't see how flying a military plane to an air base you are ordered to for official duty can be considered "personal transportation". That's military buisness.

mmarshall

How many of you on CL still own or drive an RX-8? Let us know how many miles you've gotten out of it, and how reliable the engine has been.

LexFather

Great review Mike. Amazing how the rotory engine is so small and produces good power. Wish it was more economical though.

mmarshall

Thanks.

Considering its small size (1.3L) and lack of a turbo, the RENESIS double-rotor engine, as you note, does produce relatively good power.....232 HP and 159 ft-lbs. of torque, which is the better part of 2 HP (1.78 to be exact) per liter and over 100 ft-lb. (119.5 to be exact) of torque per liter. But torque strongly lags HP, HP peak is at an enormously high 8500 RPM like the early Honda S2000 VTEC 4, and even the torque peak is at a high 5000 RPM, with a sharp, peaky curve. Below that, there is simply is little torque, any way you look at it. Admittedly, the rotary has some great features. It revs as smooth as an electric motor or turbine, makes very little engine noise (although the exhaust has an unpleasant flat, nasal sound), is difficult to over-rev and damage it unless you really get carried away with the gas pedal (computers will shut the fuel off if things get too high), is extremely small and light as far as auto engines go while helping to makie for ideal weight distribution, and is relatively simple to repair or rebuild if needed. It is also unique among today's cars.....the RX-8 is to only production car in the American market with it, making it, IMO, a potential collector's item.

But good power for a micro-sized engine like this is one thing; having enough power to make it a good sports car engine is another matter. Despite ite 232 HP, this engine, for the reasons I described here and in the review, IMO simply doesn't cut it as a sports-car powerplant the way the twin-turbo rotary did on the fast and agile 1993-1996 RX-7....and even that engine was a little flat at lower RPM's. No matter how you cut it, a small rotary, especially a non-turbo one, is just not going to be a torque monster like a Dodge Viper or Corvette Z06.

The gas-mileage problems you cite are primarily related to the fact that a rotary is unlike a four-stroke piston engine where the spark plug fires the air-fuel mixture only one out of four times in its repetitive motions (intake/compression/power/exhaust), or, in some cases, shuts down the cylinder/valve action or fuel flow altogether to save fuel. A rotary effectively functions as a two-stroke engine because the spinning triangular rotor turns inside a slightly ellipsoid-shaped chamber while its rotating tips (the aforementioned apex tip seals that tend to wear quickly), seal the chambers off into intake/compression and power/exhaust modes. The air/fuel mixture gets sucked in through ports rather than conventional valves.....same with the exhaust gas as the rotor pushes it out the exhaust port. So the spark plugs (each rotor has twin plugs like some Mercedes piston engines) fire off the air/fuel mixture twice as often.....and at higher RPM's......than conventional piston engines. And the effect, of course, is relatively poor fuel mileage for an engine its size. Engineers have worked on this for decades with only limited success.

Same with the relatively high oil consumption. Because a rotary engine does not have a big central crankshaft, bearings, cams/rocker arms, connecting rods, piston rings, wrist pins, etc......like a piston engine, its lubrication system is far different. A small amount of oil comes in through the intake ports to help keep the apex tip seals lubed against the sides of the chambers as they spin. This, of course, means oil burned, a dirty exhaust, and high emissions, which have to be cleaned up with advanced catalytic converters and other devices. That explains not only the relatively high oil consumption but also the lack of any really low-polluting ULEV or partial-zero versions, though the RENESIS rotary, to my knowledge, does meet basic EPA and emission standards in every state, including CA.

LexFather

Great explanation there Mike.

mmarshall

Thanks.

It may seem complex, but it is really a simple powerplant in how it operates. It just has a few weaknesses, that's all.