I heard some guys standing in front of me in line to pay for books talking about the r-x7's "rotary" engine (if I heard right). one of 'em was saying how the rotary engine was more efficient, or better (better than what, I dunno) in some respects... what exactly is this rotary engine they were talking about? (sorry to bring those stupid imports into this forum, guys)

Hey, I always wanted to put a twin turbo wankel in my fiero A rotary engine is a very unique design. It does not have pistons and cylinders like a normal engine. It had a "rotor", which does the job that a piston would do in a normal engine. It is sort of a rounded triangle shape. Instead of pumping up and down, it spins around. The best thing about Wankel rotary engines is that they are VERY simple mechanicly, and therefore very small and light. I think there are something like 7 internal moving parts, it's nuts. I can't really explain too much further, look it up on the web.

Oh yeah, didn't a P-51 Corsair (the airplane) use rotary engines?

The P51 "Mustang" used a Allison water cooled v12 piston engine in the early versions. These were later replaced with a Rolls V12 and at this point the P51 became a great plane. I think that you might be confusing a rotory engine with a radial engine. The rotory is sometimes called a Wankle engine after its inventor.

The p-51 is a mustang. The aircraft rotary has nothing in common with the wankel. The wankel was available with 2 or 3 rotors(12B and 13B I think). They will rev to the moon reliably but dont develop much torque down low. They are cheap to rebuild if they dont have an internal water leak which damages the internal chrome plating.

I remember back in Australia years ago, a guy I bumped into that put a 12B wankel from a Mazda RX4 into a VW Bug!! That thing was BADASS...But yeah, they don't produce much torque at all down low. They do rev to 8500 rpm stock though, no problem at all. I helped pull a rotary outta a RX4 (Yes I do mean RX4, Australian model as well as RX7's) many moons ago. We pulled that thing in about 1 hour and by hand. No lift equipment. I would be interested to dig out the HP and mounting specs. The engine is very light. Also I believ there are FWD models.(???)

They got a really bad rap for wearing out rotor tips (equivalent of piston rings) but the reason was this: You have to let these engines warm up without load! Most folks would jump in an take off like normal (I don't but some do..) and have the need for replacement tips in 15000 miles or so. I've seen these engines go for 80k to 90k without problems if looked after, and then they used to be very cheap and easy to rebuild.

This is all based on info I had back down under years ago. I do not have any real idea of the current consensus here in the U.S. Would be curious to find out though. Might make for an interesting economical conversion depending on the availability of boneyard electronics etc.

Ozzy

Guys,

I don't know what I was thinking with the P-51 comment. I must be confused. heh

All of the mazda RX7 engines were twin rotor, though, that I am sure of.

RX-7 twin turbo, 250 ponies out of 1300cc. Now that's efficient! That was the last of the exported RX-7s to the US. Japan now has a new "RX-7" but it will not be exported. In my early days of autocrossing, the RX-4 appeared and swept its class consistently. The only mods were a free flow exhaust. SCCA then reclassified the rotary motor to a larger displacement class, even though the rotary motor had about half the displacement. The seal problem was remedied in the late 80's. Early rotaries had horrible fuel milaege that almost cost Mazda it's life. The rebuilding of Mazda by its employees after the RX-4/RX-3 mistake is an example of excellent bussiness practices (and good reading).

The last imported RX7's were a 3 rotor design and could inexpensively be tweeked to 450 hp +. (inexpensive is relative to the price of the car) I priced a Mazda rebuild kit for an 86 RX7. It was anything but cheap. Look for the Mazda rotary to return to the US as a hydrogen burner in 3-5 years. Also prepare yourself for rotary powered marine toys. The guy that designed the Supertrapp muffler has the patents to a kickbutt rotary that can pump out 2.5 HP per pound and do so with less than 5% of the emissions of a 2 stroke!

[This message has been edited by 87SC/GT (edited 03-12-2000).]

Have you seen the new rotary from the RX-Evolv. It's really something now. 10,000rpm redline. Around 250(somewhere) horsepower with no boost.

after my fiero broke, i bought a '91 Rx-7. it was anything but efficient! it had no low end power, pulling out into trafic could often be scarry... and it sucked more gas in the city than my GT did!

[This message has been edited by bHooper (edited 03-12-2000).]

The aircraft engine is called a "radial" And wasent the rolls royce engine a Merlin. and I had a friend in scool who we got his rotory to turn to 12,000. They only spin and do not have motion in many different directions so they wind up real good.

theoretically, you shouldnt be able to wind the engine out... of course there isnt a tranny made that could handle that.

As one of their project cars, "Grassroots Motorsport" magazine put a fuel-injected Mazda rotary in a Triumph Spitfire. They're claiming 0-60 in less than 5 sec and 1/4 mile times in the 12's!

I also saw an A/H Bugeye Sprite at a Brit car show with a carbureted Mazda rotary. A lot of the hardcore Brit guys were giving the owner a hard time for installing a rice motor in a British car. I think they were just jealous because they couldn't keep up with him!

Now the term "wind out" referes to something different. I am talking about grenading