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13b vs. v8


renesis

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Posted

Hey, new here, got a mazda rx-8 and a chev truck. Juat wondering if you guys think the wankel is more efficient than a pushrod v8? I know the usual stuff like the v8 will have more torque, the rotary has better reliability, stuff like that, but what do you guys think??

Posted

I think the v-8 Bigger=more potential. Although the rotory is a hella motor. It's kinda tough comparing apples and ornges. Being this is a truck site and the itty bitty rotary would not work at all in our trucks your gonna get v8 answers.

Posted

potential? the rotary is 1.3L.......if you could make one as effecient and powerful at, say 5.3L, we'd watch the power output swallow the LS7. too bad they haven't been engineered enough to see their full potential(besides the 787B LeMans car).

 

It's kinda like the BMW inline 6. a few years back their then head engineer thought that I6's would take a back seat in the M3 to a V-8, as will happen in the next generation M3, because they had maxed the potential of the I6.....but look now, they have a new magnesium block and redesigns which pulls another 28 ponies out of the now much lighter same size block......

 

what I'm saying is that the current 333HP M3 motor, if reworked with the new mag magic, might see close to 400 in street form(since they have some version running 350HP already), out of a 3 and a hlaf liter six cylinder.

 

 

same applies to the Smallblock, GM is stil suprising us. seeing the new 303 hourse Gen-IV 5.3L car engine.

 

but overall, the rotary is very promising, just not MPG-happy, which is why currently it's probably not being greatly pursued.

Posted

I have respect for the Felix Wankel rotary as it has been a design that has been around since 1955, the 12A model when it was introduced to the US in 1979, and the 13B in 1984. Although I'm not really a fan of the imports, I will say that the two cars I like are the Nissan Skyline and the Mazda RX-7. Everthing else just doesn't appeal to me. The RX8 is kinda growing on me though.

Posted

I had a race car a few years back with a 13b in it. The Wankels are cheap, reliable, really cheap to modify, and can make a buttload of horsepower. On the down side, they are really not fuel efficient at all, noisy as all get out if you open up the exhaust, and don't make low end torque at all.

If you have a small car (which is what the 13b is designed for), they are a lot of fun. I can't see anyone making one big enough for a serious truck motor, mainly due to the lack of fuel efficiency.

 

On our racecar, (a Mazda 808 body on a chopped, shortened, and lowered Datsun truck frame) we purchased a 13b from "The Rotary Doctor" in Southern California. That motor made 200 hp on the engine dyno. Doc said that rpm was safe up 13,000, but the power would begin to fall off at about 9,000.

That motor cost us $1000 in 1987.

Our main track rival drove a Ford Pinto (another mini stock favorite) and it cost him over $4,000 in trick parts to pass us.

 

If you can find a rotary motor in something that you might want to build a little street racer/ricer, my advice is to do it! They are a lot of fun!

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