Zeno~SPARTA~ Posted May 15, 2009 Share Posted May 15, 2009 As some of you know I have a Mazda RX8. This is the latest in a series of rotary powered cars. I admire the rotary engine for its simplicity and Mazda for continuing to develop this technology. Doktor Felix Wankel built the first prototype of the rotary engine for NSU in 1957. when they eventually built the futuristic (in its day) RO80 it bankrupted them as a result of engine failures, many disgruntled owners dumped the engine and fitted a Ford V4 from the Corsair. The design was licenced to around 20 companies and a few of them had a go at instaling them in their vehicles, the most notable being Citroen and Mercedes but these were either recalled or abandoned. Norton built the Commander with a twin rotor 588cc 85hp bike. Mazda engineers have been working on the engine design from the outset and it is they that produced the first reliable rotary engined car, the cosmo (1963 - 1965). Eventually they built the legendary sequential twin turbo RX7 FD (as seen in fast and furious). sadly the engine of the RX7 failed to meet the newer emmisions standards and commercial Rotary production stopped. However Mazda had been racing GT cars and built a series of 3 and 4 rotor engines culminating in the R26b which in the Mazda 787b won at Le Mans in 1991 The 13b - MSP Renesis engine used side ports to eliminate overlap of exhaust and intake gases which was the cause of its higher emissions in its peripheral port version. Overlap is what caused the demise of the 2 stroke engine but engineers have found a way to overcome the porblem there as well. With an engine that met Euro 4 emissions standards Mazda Launched the 192 and 231 hp RX8 in 2003. As I have said before the rotary engine is a simple piece of kit and here is an animation explaining how it works &"> &" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350" /> This video shows a Mazda Technician building the engine in an hermetically sealed clean room &"> &" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350" /> And this last video shows a bunch of good ol boys helping there friend teardown and rebuildan engine in 3 days. &"> &" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350" /> Link to comment Share on other sites More sharing options...
Zathrus~SPARTA~ Posted May 15, 2009 Share Posted May 15, 2009 I also have always admired the simplicity of this engine. It has always been one I have wanted to "play with" when the technologies and component composition allowed. Link to comment Share on other sites More sharing options...
MedicSN6 Posted May 15, 2009 Share Posted May 15, 2009 WOW that was incredible. I have done some minor work to all of my vehicles, such as belt changes, radiator hose replacements, as well as the normal tune up stuff like plugs and wires. But damn, to pull and repair then reinstall and entire engine... in three days... well done guys. It would have taken the dealer 3 WEEKS to do it. Excellent videos Zeno. Thanks. Link to comment Share on other sites More sharing options...
Athlon64~SPARTA~ Posted May 15, 2009 Share Posted May 15, 2009 (edited) In my day I have pulled big block chevy engines out and installed a new one back in and the truck done in 2 days, That included cleaning and changeing the intake manfold out as well. But dident rebuild it, just a engine swap. Edited May 15, 2009 by Athlon64~SPARTA~ Link to comment Share on other sites More sharing options...
Zeno~SPARTA~ Posted May 15, 2009 Author Share Posted May 15, 2009 I find the contrast between the clean room build and the backyard build funny. Link to comment Share on other sites More sharing options...
Xross Posted May 15, 2009 Share Posted May 15, 2009 That is truly amazing. Other than the part where you need a rebuild at 51,500 miles. None the less that is one creative engine design. Link to comment Share on other sites More sharing options...
Zeno~SPARTA~ Posted May 16, 2009 Author Share Posted May 16, 2009 That is an unusual failure but the engine is not the most robust (plus he had afitted an aftermarket turbo). On the UK RX8 forum 20 people have had new engines (replaced by Mazda), One guy is on his 3rd but I think he lacks mechanical sympathy. Most failures are due to loss of compression, which one way or another is down to the seals on the rotor tips. There are 2 oil feeders in the tips if there is ever an issue with those feeders the tip wears and that rotor will lose compression. The newer R3 RX8 has 3 oil feeders in the tips which disperses the oil more uniformly and actually reduces oil usage. The pros of this engine are that it is compact and light so its sits far back and low in the engine bay. The power to weight ratio of the engine is high. The RX8 has 50:50 weight distibution mostly as a result of the engine (My TTS is 58:42 by comparison). This make the car inherently stable at the limit of adhesion. The negatives are high fuel consumption under light loads. Not as robust as a standard piston engine at this time. Linear power delivery, unlike cars that go on boost or on cam the Stock RX8 lacks the pushed back in the seat sensation. The car in the last film has had a large turbo charger added and so performs accordingly. Link to comment Share on other sites More sharing options...
NoScream~SPARTA~ Posted May 16, 2009 Share Posted May 16, 2009 I'm going to watch the videos again, nice..... Link to comment Share on other sites More sharing options...
Zeno~SPARTA~ Posted May 18, 2009 Author Share Posted May 18, 2009 Johnny Herbert (who drove the 787b to victory at Le Mans) demonstrates the RX8 R3 &"> &" type="application/x-shockwave-flash" wmode="transparent" width="425" height="350" /> Link to comment Share on other sites More sharing options...
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