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crazymarcel

RX7

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Was out the other night and came across an old G reg Mazda RX7, After seeing his face as my car started to pull past his in second and third

 

Just wondered what kinda engine they have in them?

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lol, ohh not so impressive then.

 

I'll get my coat

 

No mate these pump out some serious bhp.

 

 

Thats not so bad then, Was gonna say it looked quite sporty in an oldish sort of a way. Never seen one before.

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There are a lot of RX7s on the road that have had the rotary engine ripped out and replaced with a conventional one. It's cheaper than the 100,000 miles strip-down-and-rebuild-the-engine service, probably.

Wankel rotaries are amazing engines, very difficult to get your head around how it works, but they produce HUGE power from tiny capacities by eliminating all the stupid reciprocating motion crap from your normal piston engine.

They aren't cheap to maintain tho. You think it costs a lot to have a G60 refurbed...

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It's basically 3 combustion chambers in one tiny block isn't it? The hardest thing about these engines is the piston lip seals. Only Mazda have prefected it. Other people have tried and failed, immense oil consumption being the result of their efforts. The manufacturing precision required for a Wankel (something the Japs excel at) is far greater than that of the G lader, to give you some idea.....which in itself is an engineering nightmare, again, only VW had the technology to do it.

 

Wankels rev like crazy and behave like a VTEC, i.e. no torque to speak of below 5000rpm and then all hell breaks loose. As Clarkson put it "The RX8 has a buzzer on the dash that comes on at 8000rpm telling you that a gear change might be a good idea...."

 

K

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148bhp for the non turbo up to 1989, 197 for the turbo which was introduced in 89, so really it could have been either!

 

The later turbo's kick out 237bhp and are rapid i know this cause my mate had one. :twisted:

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It's basically 3 combustion chambers in one tiny block isn't it? The hardest thing about these engines is the piston lip seals. Only Mazda have prefected it. Other people have tried and failed, immense oil consumption being the result of their efforts. The manufacturing precision required for a Wankel (something the Japs excel at) is far greater than that of the G lader, to give you some idea.....which in itself is an engineering nightmare, again, only VW had the technology to do it.

 

Yep, miracles of engineering. Effectively 2 cylinders in a single unit, as you say Kev.

Basically there's an eccentric cam in the centre of a larger three-pointed cam. The large cam moves around inside a "cylinder head" surface making contact at each point, and thus sealing the gases into one side of it. That side is then squeezed against the outer surface (by the shape of the outer surface) to provide compression and then it ignites to push the cam away from the cylinder wall, this pushes the central eccentric cam the *other* way. Basically because the whole engine turns together, there's no need for a flywheel - it *is* a flywheel, so the power that comes out is EXTREMELY smooth. But those seals are a nightmare. They need completely replacing once every 50k miles, which means stripping the whole engine out. The japanese are the only people who ever managed to get the engine to last 50k...

 

Take a look at:

 

http://travel.howstuffworks.com/rotary-engine.htm

 

for some more details.

 

rotary-engine-intro.jpg

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http://travel.howstuffworks.com/rotary-engine4.htm

 

Nice bit of flash animation showing EXACTLY how it works. (Well except how the motion is passed to the central crank...)

 

Dunno if the following will work:

 

src="http://static.howstuffworks.com/flash/rotary-engine-animation.swf" quality="high"

pluginspage="http://www.macromedia.com/shockwave/download/index.cgi?P1_Prod_

Version=ShockwaveFlash" type="application/x-shockwave-flash" width="405"

height="300">

 

It seems not... Mods - can you make this work?

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I am probably very wrong, but i remember reading an article ages ago about this kind of engine being made buy audi years ago, i think in the 70's. It didn't work very well though if i remember correctly, then mazda took the idea and made it work. Again sorry if i am way off, but for some reason i thought it was audi. :oops:

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It seems not... Mods - can you make this work?

 

Sorry - that option isn't possible at the moment.

 

Would probably only piss off people on 56k though, having the page take an age to load.

 

Presume it's the same as in the link?

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theres an RX-7 down the road with around 1100bhp its called the pink pather and its still a bag of sh1t

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I am probably very wrong, but i remember reading an article ages ago about this kind of engine being made buy audi years ago, i think in the 70's. It didn't work very well though if i remember correctly, then mazda took the idea and made it work. Again sorry if i am way off, but for some reason i thought it was audi. :oops:

 

 

close........NSU had the R80 in the late 60's early 70's with a "wankel" engine...........NSU eventually became audi........but IIRC mazda have had wankel engines on the go for a lot longer than the RX7 has been out.......in fact i'm pretty sure from the early 60's mazda had a rotary engined motor :wink:

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I am probably very wrong, but i remember reading an article ages ago about this kind of engine being made buy audi years ago, i think in the 70's. It didn't work very well though if i remember correctly, then mazda took the idea and made it work. Again sorry if i am way off, but for some reason i thought it was audi. :oops:

 

 

close........NSU had the R80 in the late 60's early 70's with a "wankel" engine...........NSU eventually became audi........but IIRC mazda have had wankel engines on the go for a lot longer than the RX7 has been out.......in fact i'm pretty sure from the early 60's mazda had a rotary engined motor :wink:

 

Cheers for the reply vr6storm, i just couldn't remember it right! :)

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close........NSU had the R80 in the late 60's early 70's with a "wankel" engine...........NSU eventually became audi

 

*cough* RO80 *cough*

 

/anorak mode :wink:

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It seems not... Mods - can you make this work?

 

Sorry - that option isn't possible at the moment.

 

Would probably only p*** off people on 56k though, having the page take an age to load.

 

Presume it's the same as in the link?

 

No worries, that's very true aswell, I forget that not everyone has broadband!! ;)

 

Yes it's the same as in the link itself.

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but do any of you remember the Madza 787B Le mans car? Had 4 rotors and a few turbos I believe... and something like a reliable 800bhp!!! Then there's also the incredibly RX7 triple rotor, limited anniversary edition only originally intended for japan.. somewhere on the net there's a movie of 1 flipping over at 200mph..... its impressive

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close........NSU had the R80 in the late 60's early 70's with a "wankel" engine...........NSU eventually became audi

 

*cough* RO80 *cough*

 

/anorak mode :wink:

 

 

:oops: :oops: :oops: ......totally right Henny :oops: :oops: :oops:

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