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Discussion Starter · #1 ·
Today a guy was telling me how superior his 13b rotary in his rx7 was to a ford small block v8, he said that "the 289,302,and 5.0 cant touch a ratary" in performance. He said that they rev faster and are more reliable. he even went as far to say that I should put one in my 68 stang(Id never do this though). how much of this is doodoo and how much is real?
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Well, I guess Ford, Chevy, and everyone else need to pull their heads out, because none of them are too interested in the rotary design. Rotary is less efficient and pollutes worse, because it can't achieve the compression ratio that a piston engine can. Also, I don't know if rotary engines last longer, but I would think that with the only point of friction being the three tips of the rotor (or rather a small part of one side of each tip), that they would wear rather quickly, much faster than the rings and bearings in a piston engine. And as far as revving faster, they might have a slight edge, but overall, how fast an engine revs depends on the power it's producing in proportion to it's rotating and reciprocating mass. I doubt you could build a rotary engine that revs as fast as a top fueler.
 

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Actually in a magazine I have seen a Curtis Wenkel Rotary in a 65 Mustang before. It is my understanding that the rotaries have little bottom end torque. I believe that they weigh about the same. Ask him if one of his rotaries can put out 2200 horse. If so I would like to see it. I know that the 2200 horse example is for racing only, but it is quite interesting to see so much power come out of a small package. I have heard of people pulling rotary engines and putting in V-8, but never the other way around. Think of the RX-7 guys as in the same class with the Supra guys.
 

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I had a '93 RX7 twin turbo rotary. Not much low end torque, but plenty of high rpm horsepower. These engines are very light with far less moving parts. However, they don't last long. 60-80k miles is normal for these cars before the case wear necessitates replacement. Unlike piston engines, the engine cases can't be machined when they're worn. I liked the car, but it felt fragile. I always thought I was going to break it when I drove it hard.
 

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Well, just to be the spoiler here I have seen 2 RX-7's deep in the 7's... so they're not all bad. Depends what you like & what you wanna spend... I'll keep my Fords!
 

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take a look at this http://www.haltech.com/Who_s_Hot_/RX7/rx7.html

i've seen alot of movieclips with rotary race cars, and they are pretty damn fast ..

the big advantage of the rotary is that all the moving parts only travel the same whay, not like the pistons that have to change direction .. and there is alot less moving parts in it...

as i have read they have fixed many of the problems, such as performance and polution.

and why wont topfulers use them ? i think it might be that nobody produce a big enough engine ..
 

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Yeap ... In terms of pure efficiency as per the laws of Physics and Geometry ... Rotory is far and away the superior engine.

But, out in the real world ... I guess there are reasons why the old piston engines seem to rule the roost. I'll let others debate that thought




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<font size=-1>[ This Message was edited by: MonsterMach on 6/25/02 4:42pm ]</font>
 

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Fuelers can't use them, rules. Just like they can't use current turbine engines in jet cars. Go faster than a piston driven car, lose your license! Gotta love the powers that be! Personally I like rotaries! I had a RX-2 some years ago & put a B&M on it... MAN!!!
 

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Rotaries are cool, they're just not me. Me=Big Diesel fan, and a rotary engine is quite the opposite, and now I think about it, they're practically complete opposites.... I guess thats why it doesnt appeal to me
 

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Yes, Rotaries can be built to run as good or better than the v-8's, but when you get through spending that much money, you could've built a 1000 HP big block. Not to mention the rotaries sound like pissed off bumblebees. I prefer the v-8 roar anyday
 

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Discussion Starter · #12 ·
how much lighter is a rotary than a small block v8? the new rx8 has like 150 lbs of torque and 250 hp that doesnt seem so revolutionary to me!
 

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Wankels (the rotaries we know are not true rotaries) are neat little engines. I don't recall them being all that light, but they are compact. Dr. Michael Seal, of the Vehicle Research Institute of Western Washington University, warned me not to rev them above 10,000rpm. FYI, the VRI did some early development work for Datsun. Because the shape and location of the ports act as the cam and head, you can build a wild beast with little more than a grinder. These engines are not terribly emissions friendly. If emissions are ignored, these little 1.3 liter engines are capable of impressive feats. (I still prefer the sound of a v8 with a loping idle, but I have to respect the Wankels.) Too bad GM pulled out of their Wankel development.
 

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Another problem with rotaries is that they're VERY fuel inefficient, and thus, pollute a lot. A 1.3L RX7 turbo makes 255hp, nothing to shake a stick at, but it's getting 17/25 mpg city/hw, for a 1.3L, that should make you want to puke, considering a new mustang GT makes 260hp out of its 4.6L engine, but gets 18/26mpg(not a huge difference, but the point is that the 4.6L is 3 and a half times as big). A camaro withs it's 5.7L 325hp engine gets 19/28, and it's almost 4.5 times the size of the 1.3L. Now I know, they're totally different technologies blah blah blah, but the point is that if the engine is THAT fuel-inefficient, it's gonna pollute LOTS, and most people aren't going to want to drive it.
 

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Discussion Starter · #15 ·
Well now that ford owns mazda no telling what we might get!
 

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Discussion Starter · #16 ·
Dam, I just read the link from the other post and that rx7 is fast, 9.6 ets and its still streetable.

Can a 289, 302, or a 5.0 survive 22 lbs of boost and a shot of 75 hp Nitrous? if it could i dont think it would be streetable. The turbo 13b rotary produced 645 hp and over 470 lbs of torque. If the small block could survive that, how much hp and torque do you think it would produce?
check you later,

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-Kenny-
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A Mustang is a poor mans Ferrari!

1968 289 coupe, 65B, my car.
1968 302 coupe, 65A, my dads car.

<font size=-1>[ This Message was edited by: HitmanKB on 6/26/02 3:39am ]</font>
 

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HI ALL
I use to run a mazda 12A at the round d round track. 85 + mph in second gear.
Hears a mazda going bang durning a burning out contest. Servers him right for doing donuts on the starting line.. Right had drive.
Tim

http://204.244.174.73/~blak94gsx/movies/other/rx7_bang.mpg

DARN
The page must be to OLD Sorry.


<font size=-1>[ This Message was edited by: pedal2themetal45 on 6/26/02 4:42am ]</font>
 

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20 years ago ford tested the rotary and gave up on the problems. that is why mazda got it to begin with. ford has owned 25% of mazda for that long. KB
 

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Down in Aus they have the mazda 3 rotor engines. I always thought it might be neat to stick one of those into a fox mustang. I think the rotary kinda falls into the same grouping as the FE, because ya can always build something else cheaper, but if ya gotta stand out you can, and still make impressive power.
 

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I own a 1988 mazda rx7 turbo II. I put on a full exhaust system, with no cats, and have made a cold air induction system, the rest of the engine is stock. The car makes about 260 horsepower and is one car length slower than my friends ls-1 WS6 firebird, all for $5000 including the car. Rotary engines with accesories weigh about 250lbs where V8's weigh 500. Rotaries are awesome engines, but american companies just can't make them. They tried back in the 60's with a 390 some odd cubic inch corvette concept but that completely defeated the purpose of large power output from small displacement. Rotaries get no worse gas mileage than V8's and easily produce more power with less than half the displacement as a V8. But for their size, 1.3L they do get very worse gas mileage than an equivalent four cylinder. They definitely don't make the all out torque when they are naturally aspirated, like a v8 would, but with a turbo the rotary engines make peak torque at about 3500 rpms and pull all the way to 8000, and this is on a stock 2 rotor engine, they can be built up to pull to about 14000rpm. What they may lack off the line they make up for by pulling all the way through the rpm range. And the new Rx-8 has a 10000rpm redline from the factory I believe.

Well, I am a lover of V8's, but I've become a Wankel head too, they are really amazing engines, and even more amazing, was Felix Wankel, the man who designed them back in the 20's. There are some really interestind sites about rotaries if anyone is interested. But take warning, you might become a Wankel Head...

http://www.monito.com

http://www.rotaryengineillustrated.com

Oh yeah the 1991 Mazda 787B Le Mans racer...
Only Japanese car to ever win the le mans/ only rotary engine to win. It was a 4 rotor 2.6L engine that put out over 700 horsepower and 450lbft of torque. Pretty amazing for an engine that's only been around for 48 years.


<font size=-1>[ This Message was edited by: kleetuz on 6/26/02 10:27am ]</font>

<font size=-1>[ This Message was edited by: kleetuz on 6/26/02 10:27am ]</font>
 
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