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I did some searching and didn't find much on the subject. I was wondering if anyone’s considered the idea. I know the Rotary engine out of the Mazda RX-7 and RX-8 isn't that big, has a low center of gravity and (especially in the RX-7 with a twin turbo) was not a bad engine. I realize that the engine compartment on the Elise is not even close to as big as the engine compartment on the other cars, especially where I’ve seen an RX-7 with a Corvette V8 stuffed in it. And also the fuel mileage isn't as good and that engine does burn some oil. But I was just wondering if anyone's considered or tried the idea of a rotary Elise.

If this has already been discussed please just point me in that direction. I did some searching but wasn't able to find anything.
 

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You can do a search here and elsewhere on renesis. About 4-5 years ago there was all sorts of wild speculation here and elsewhere about the lump that would used in the new elise. Think the issues came down to weight of the engine, longitudinal fit in the engine bay, and the Elise needing a fwd gearbox.

Jeff
 

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The rotary engine may be small in dimension but it is quite heavy at 480 some odd pounds. There was an article in sport compact car where an rx7 was converted to an ls1 v8 and the v8 was only about 40 lbs heavier. Remeber the rotors are made of iron.
 

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yeah, what he said, plus theres an awful lot of other junk that goes with the rotary engine to keep it happy.
 

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I do not know about the current Renesis motor but there were aluminum parts available for the 13B motor to reduce the weight significantly.
 

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ZAMMY1 said:
yeah, what he said, plus theres an awful lot of other junk that goes with the rotary engine to keep it happy.
Like a really, really, really big radiator.
 

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A fully dressed Renesis sans airbox weighs 267.5lbs. Mazda recently unveiled a Mazda Premacy (5) with a duel-fuel renesis (hydrogen and petrol) and a transaxle. I think this would be a great motor for the Elise with very little in weight gain. The 2zz weighs 253lbs or so.

Granted, for less money, you could go forced induction and make more power and still have better fuel mileage. That is the problem with it.
 

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I am quite sure the engine would fit into the engine bay of the Elise. A rotary engine stripped of its ancillaries is only about the size of a 5 gallon pail (I had one of these from my old track car laying around my garage for years). The largest problem would be trying to mate it up to the Toyota transaxle in the Elise. The rotary was designed for a front engine/rear drive setup so a lot of conversion work would be required to get it to fit. Another problem would be fabricating all the mounts necessary to hold the engine in place. Another difficult thing with a rotary is trying to get rid of all the heat these engines produce. The temps at the exhaust ports can reach 1600 degrees F and will melt standard exhaust tubing. Competition headers for rotaries are usually made from 1/8" steel (heavy and hard to work with) and I even managed to melt a couple of these on my old Rx-7 (ever seen the 6 foot flames that shoot out the tail pipe of an Rx-7 on lifting off the throttle--great for backing off that guy on your tail at the track:D ). Just the heat build up in the engine bay would be difficult to deal with on the Elise and you need to have a much more robust cooling system as well as a much better oil cooler. The rotary engine is cooled mainly by its oil and the large oil coolers used on the rotaries are a proprietary Mazda design that is much more efficient than any normal cooler out there. Here is a tip for you track junkies that are running high oil temps--Put one of these Mazda oil coolers on your car with your standard engine and you will actually have to put in a thermostat because the oil will run too cold. The last problem I can see is that even though the rotary puts out a lot of HP for it's size, there is almost no torque. If you think the Toyota engine has no torque, you haven't driven a rotary. The lousy gas mileage doesn't help either. A typical day at the track returned about 7 mpg and on the street you were lucky to get over 18 mpg. I had to carry a lot of gas with me to the track to make it through a day. Overall (and I love the rotary engine) I can't see an advantage to converting an Elise to a rotary engine.
 

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tesprit said:
If you think the Toyota engine has no torque, you haven't driven a rotary. The lousy gas mileage doesn't help either. A typical day at the track returned about 7 mpg and on the street you were lucky to get over 18 mpg. I had to carry a lot of gas with me to the track to make it through a day. Overall (and I love the rotary engine) I can't see an advantage to converting an Elise to a rotary engine.
The toyota engine has 138 ft-lbs of torque. The Renesis has 162 ft-lb of torque. Maybe in an car as heavy as the RX-8, torque is a serious problem, but it should be fine for a lotus.
 

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Problem is not the size, but the availability of a transaxle. No Mazda rotary engines are configures as FWD cars, so you'd have to make the Lotus a front-wheel-drive, rear engine car without some very serious engineering. Which is pretty pointless.

The wankel rotary engines are gutless (yes even the renesis), with very little torque. You might as well keep the 2ZZ. 24-ft-lbs is not that much more, and definitely not worth all the trouble for an engine swap, let alone the maintenance nightmares of rotary engines (apex seals and oil consumption).

'Greg
 

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If you want high revs strait up to 9,000 rpm, build up the internals. If you want more power, look into a supercharger or turbocharger kit, or quite possibly a custom build. Those will be much cheaper and more practical and reliable than formulating brackets, placement, transmission, ECU, and cooling solutions for a new engine.
 

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If you want high revs strait up to 9,000 rpm, build up the internals. If you want more power, look into a supercharger or turbocharger kit, or quite possibly a custom build. Those will be much cheaper and more practical and reliable than formulating brackets, placement, transmission, ECU, and cooling solutions for a new engine.
Yeah right , but a rotary engine is a rotary engine and no other engine is that sweet to drive...The sound is amazing, it is a pure engine for any sport car. I cant agree when you said it is heavy weight. I removed mine twice and if I would be a little stronger and taller I could have moved the engine myself once it was out of the car. The problem is the fuel economy and I think that it is a lot lot more reliable now with the new renesis engine from the RX-8 than it was on my 3rd gen...:D Anyway, in the best world. it would be really cool to see a Lotus elise or exige go like hell with a rotary sound and why not with a turbo an a nice BOV sounds. hahahaha I can imagine what it would look like! BBRRRRAAAPPPPPPPPP !! TTTSSSSSSHHHHH!!!
 

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If you are serious, then build a triple rotor, add a T35 turbo, and you got an honest 700-800 HP monster with only 3 moving parts at 9250 RPM! Either Pineapple Racing or A-Spec Tuning can do it. Definitely going to be a challenge fitting a transaxle in their but if anyone can do it, it would be either of those two shops.
 

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the honda K20 with a little boost is a much better engine and most of the work has been done. Find an old datsun 510 or 240 and put a big rotory in it.
 

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Rotary sound is truly unmatched, imo.

Im a huge fan of rotary engines.

http://www.hurleyrotary.com/
Quad rotor.
<object width="425" height="355"><param name="movie" value="http://www.youtube.com/v/Au7F2ttEXWU&rel=1"></param><param name="wmode" value="transparent"></param><embed src="http://www.youtube.com/v/Au7F2ttEXWU&rel=1" type="application/x-shockwave-flash" wmode="transparent" width="425" height="355"></embed></object>
 

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I raced 2 different Mazda's (SCCA). Never missed the lack of torque. Most of the time the RPM's were between 6-9200 rpm. The rotors were pinned, the gears hardened, special seals, full bridge-port, etc. That's the lump-lump (bridge-port) you hear in the drag car above. Love it! :p

GAS HOGS...but a lot of fun watching people block their ears as you cracked it in the pits. rotfl The engine was one of the most reliable and bullet-proof engines I have ever run.

It seemed like the more gas we could throw at them, the more power they made. I'd love to have a turboed 13B in an Atom-type of car. It's all about the noise and rpms...loved to hear it scream. :eek:
 

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