RotorBoy

Saw a link on autonews.com that stated the following:

Mazda's new president plans more high-profit SUVS for U.S.
Mazda Motor Corp. may send more SUVs to the U.S. market as part of a broad push to improve profitability there, the automaker's new president said last week.

Unfortunately, you have to pay to read. Anyway I thought this was interesting. I wonder what it would be like to have a rotary SUV!

mikeb

wonder what kinda hp a rotary suv would have

j1mb0x99

I don't think a rotary SUV would be a very good idea at all. Rotaries are Quick and Small. SUV's are Big and Powerful. With the lower torque rotaries produce I think they should stay away from big, heavy vehicles.

just my 2 copper pieces.

-JiM

RX-GR8

agreed

vipeRX7

rotaries do not have low torque!!! What do you expect from a 1.3 liter N/A engine? If a rotary was the size of the engine of a Nissan 350z, assuming a linear torque increase relative to displacement, it would have ~420 lb ft of torque. The problem with putting a rotary in an SUV is that to achieve that kind of torque, gas mileage would probably be horrible. Unless ... would a high-displacement de-tuned renesis produce decent torque with half-decent gas mileage?

j1mb0x99

Good point... I am always forgetting how small this engine really is. You said though, that you assume linear torque increase. Do you know for sure if it would be relatively linear? How many liters are all the different Rx-7 engines (NA) and how much torque do they produce.

--JiM

vipeRX7

I don't think the torque increase relative to displacement is exactly linear (frictional losses increase too much?), but I'd say it's fairly near that. Unfortunately, for rotary engines, I can't really back that up, because the different displacement engines were generally tuned in different ways. The 13B had 6 ports (there may have been a 4-port version?), and the 12A had 4 ports. The turbo-20B from the Eunos Cosmo was arguably underrated to meet the Japanese 280 hp rule, so I can't make any comparisons between the 13B-REW and that engine. Even then, the 13B-REW made from 255 to 280 hp in various RX-7s. So I can't really think of any two Mazda rotaries that were exactly the same except for displacement. What I am basing the statement about torque on is piston engines, which have a roughly linear torque increase. All I can say for sure, though, is I've never heard of an N/A 1.3 liter piston engine producing 159 lb/ft of torque--that's 122 lb/ft per liter! :D For comparison, the Z makes roughly 80 lb/ft per liter, and the S2000 makes about 77. But then, it really depends on how you define displacement ...

vipeRX7

sorry for the double post ...

CERAMICSEAL

It is generally linear. A good example is peripheral port race engines. In proper tune they can produce approximately 110lb/ft
per rotor(80mm width).That equates to around 170lb/ft per L in race trim. This applies to 2,3, and 4 rotor engines. A 4rotor engine of 2616cc dispacement can produce as much as 450lb/ft of
torque at between 7500 to 8000 rpms.
All that being said rotaries are still best suited for light automobiles due to their torque characteristics(rpms at which peak figure is developed etc.) Also sportscars can take advantage of the rotary's size and shape, allowing low hood lines and wondrful weight distibution.