ckblum

Has anyone ever swapped a rotary engine in? I can't find any info on it, I've seen it done in a Ranger once though. Just wondering how much work it would be.

Hayes

Not worth it. They are very temperamental engines, and they are not efficient at all. In an RX7 / RX8 a 1.3L engine only gets 12 mpg. My 2.4L get's 15-17 in a truck that's lifted with 33" tires.

ckblum

Yea but how much power does the rotary make compared to the 22re? I love the 22re but I also like how the rotary is small and puts out lots of power. I just wanna see if anyone has done it and how simple it was. I might be building a short course truck so MPG isn't really an issue just power to weight ratio.

ozziesironmanoffroad

but look at the power that little engine produces in the rx8. those little things damn near fly. true though that they are very temperamental. theres also something about how when u change the oil, you have to fill it, then run it until its warm, or it wont start back up and be fubard.... or something like that. i love that they can run those high RPMs that not even big block chevies can run with no fear of destroying the motor.
but look at the car its in... lighter than fiberglass. that motor in a toyota truck is like putting 40s on a stock IFS... it will work, but it will SUCK.

ckblum

An RX7 weighs around 2500lb. A single cab short box 2wd Toyota, gutted down, no box just fiberglass bedsides and fenders w/cage shouldn't be a whole lot more. I dunno just a thought, it would have to be within the rules still so I don't even know if a Rotary is legal, I know they are banned in a few other motorsports organizations.

RobD

Inefficient, poor fuel economy, low torque numbers...and no adapaters to hook it up to your drivetrain.

Not worth it.

ckblum

Alright, well maybe I'll look into a 3.4 swap. What kinda economy are people typically getting? I plan to run 31-32" tires max.

ozziesironmanoffroad

id look into a 3.4 swap, like you said. economy anywhere from 10mpg to like 24mpg. maybe a little more. i dont have one, so i cant say for sure. a buddys taco, lifted (bro), 4" blocks, 35s, he gets on it all the time (lead foot) gets around 9-10mpg. i dont know everyones situation, so i generalized lol.

waskillywabbit

iTrader: (-1)

Yep, pointless.

RobD

Highway, running 33" All Terrains, I get around 24 mpg on my 3.4 swapped 91.

It works out to around 300 miles per tank. Mixed city and highway, it's a little lower, but still better than my old 3.0.

85excab

if u want light weight powerful and still yota, go with a 2rz/3rz.

Hayes

Got with a 3.4 or even a Chevy 350. The rotary (Code named Wankel) is rediculous. A piston uses 3 piston rings, a rotary uses 8 apex seals. If the engine detonates once, it's time for a rebuild.

As it was said earlier, they make decent horsepower but no torque. Get yourself a good reciprocating engine and make it more powerful. Use a 3.4 with a supercharger, URD 7th injector kit and be done with it.

ckblum

Is the 7m-ge a heavy engine? I found a few on craigslist for a decent price. How hard is it to fit in?

Windsor

12mpg is a heavily modded turbo model at the track, perhaps. I get 20mpg (highway) with my old carb rotary engine, ferexample.

But yes, there are many reasons to not do it -- low torque, no 4x4 drivetrains (REPU was 2wd only), no adapter plates, yadda yadda.

ckblum

I was just thinking it would be cool to throw it into a little 2wd single cab short box and have a super light short course truck.

Adam F

24mpg? Most I can squeeze out of 97 is 20.

But your math doesnt add up. 300 miles to a tank, 17 gallons in a tank. 300 divided by 17 = 17.6. Even if you diddnt use ALL 17 gallons, something like 15.5 (usually what I fill up to at 300 miles) 300 divided by 15.5 = 19.3 If you really got 24mpg you would be putting in only 12.5 gallons when you fill up after driving 300 miles.

jackwolf

X2

The wankel engine was banned from competition in some series because it had an unfair advantage over the 4 cylinder engines. They rev up to 10,000 rpm and can be tuned to produce a flat torque curve. Once they make peak torque, they stay there.

No wonder they were banned. Mazda won it's 24 Hours of Le Mans class ten years in a row with the wankel. People even use them for aviation home builds.

Have you ever seen the viral video of a gsxr 1100 engine in a smart car? That's the sort of fun you could have on the track with a wankel engine in a stripped down, street tuned yota with some gummy tires. It has a serious backbone.

The pay off is not as good if you installed one in a runner unless you jump on the highway and stay there.
Or if you do a lot of roll on acceleration at highway speeds, those things rev quick.

Or if you do fire road hill climbs.
Or if you do rally style time trials.
Or...

well the list just goes on

and on
and on
and on
and
the beats don't stop until the break of dawn.
Every girl I know, she want to get with...

Oh

never mind.

Windsor

A whole lot of errors here.

Mazda won one La Mans race with the rotary engine -- 1991. Read about it here: http://en.wikipedia.org/wiki/Mazda_787B

Tuning a flat torque curve and achieving 10000rpm at the same time is the holy grail of engine building -- every engine does one or the other, never both (some V8s and V12s come close, tho).

The rotary engine does not make a flat torque curve without adding a blower and that's a square-peg-round-hole effort, at best.

Revving quick is simply a matter of reducing rotating mass. Sure, you get a headstart with the rotary engine (all you need to do is swap out the flywheel).

RobD

I might have been a little off, but...here is the math:

Last highway trip I took, I got 505 kms on 54 liters of fuel (Canadian, eh). The mileage is confirmed by both GPS and Google. That translates to 10.7 liters per 100 kms. This is where my math was a little off: that works out to 26.4 miles per Imperial gallon, which I forgot is larger than that little gallon you Americans use. It's actually 22 miles per US gallon.

Yesterday I filled up 56 liters at a distance of 479 kms, mixed city and highway. That works out to 20 miles per US gallon.

Aside from running Mobil1, the main thing that I attribute this to is getting rid of the mechanical fan and replacing it with an electric. I noticed a 10-15% increase in fuel economy after I did that mod.

So, in essence, you're right...I wasn't quite making 24 mpg (US), but I was kicking butt in Imperial gallons.

jackwolf

A whole lot of errors here.

I'll admit, I did take certain liberties. I am no fan of the wankel engine myself but it seemed to be getting bashed, so I don't mind playing the devils advocate from time to time. But there are no errors here. At most, only a single administrative oversight brought on by the witching hour and firewater.

All right, I'll admit it. One error.




Mazda won one La Mans race with the rotary engine -- 1991. Read about it here: http://en.wikipedia.org/wiki/Mazda_787B

That first year, RX-7s placed first and second at the 24 Hours of Daytona, and claimed the GTU series championship. The car continued winning, claiming the GTU championship seven years in a row. The RX-7 took the GTO championship ten years in a row from 1982. The RX-7 has won more IMSA races than any other car model.


...and there it is.




The Mazda RX-7 has won more IMSA races in its class than any other model of automobile, with its one hundredth victory on September 2, 1990. Following that, the RX-7 won its class in the IMSA 24 Hours of Daytona race ten years in a row, starting in 1982. The RX7 won the IMSA Grand Touring Under Two Liter (GTU) championship each year from 1980 through 1987, inclusive.


...and there it is again from another angle. Both from wikipedia this time around; one for the rx7 the other for the wankel.

It was Daytona but at least I did bother to put CLASS in my original post even though I did not bother to look anything up, I'm just too lazy when it comes to posting in the public domain since I really don't care about my street cred, or do I? hmmm.





Tuning a flat torque curve and achieving 10000rpm at the same time is the holy grail of engine building -- every engine does one or the other, never both (some V8s and V12s come close, tho).

I never said at the same time, I only implied it. Some engines CAN only do one or the other. With this engine you can TUNE for one or the other or, to a certain extend, both. So, like some v8 and some v12s, you can play both sides against each other on the road to mecca. I do love naturally aspirated, silky smooth v12s, tho.



The rotary engine does not make a flat torque curve without adding a blower and that's a square-peg-round-hole effort, at best.

Agreed, nothing sexier than naturally aspirated, but it CAN be done.




Revving quick is simply a matter of reducing rotating mass. Sure, you get a headstart with the rotary engine (all you need to do is swap out the flywheel).


On a small yota truck, street tuned with gummy tires and an off the shelf rx something or the other wankel. You are going to have one hell of a good time with minimal cost. I would like to track it against other big ticket rides. It can be done for around 10k USD easy and that will give +60k USD 4 cylinder rides a run for the money. To have more fun you would have to look into a radical sportscar they rev halfway to heaven. In the meantime, I think a high revving 10k trainer would be a blast.