MR2 Yes You can Have Two engins and AWD

This is great, nuts and probably a whole lot of fun!!! And yes I would like to have one!!!!

http://www.thetruthaboutcars.com/2011/05/twin-engined-toyota-racer-works-fine-confounds-self-proclaimed-experts/

That's awesome!

That is the most ridiculous thing I's ever seen.

Cool but I can't get how it could handle decently with an auto and a stick powering wheels with different ratios all at different times.

So good!

kevlarcorolla wrote: Cool but I can't get how it could handle decently with an auto and a stick powering wheels with different ratios all at different times.

http://grassrootsmotorsports.com/forum/grm/twin-engined-cars-looking-at-you-ansonivan/32456/page1/

I had thought that to do it right you'd put a smaller engine in the front and give it an auto with a manual in the rear. Once again I'd have been wrong.

I can now see where the manual in the front could help you overcome the understeer tendancies of a twin engined car and allow you to tailor your driving style better.

I'm sure everyone of us on this list has thought of this, totally as a thought excercise of course. No one on here would be crazy enough to actually build one.

GRM:

Future issue: This thing vs. the Durocco for twin-engine supremacy!

irish44j wrote: GRM: Future issue: This thing vs. the Durocco for twin-engine supremacy!

If anyone used to read SCC when it was still around, remember.. 2004? maybe, twin engined dual automatic Tiburon. Add that to the list for a real party.

JoeyM wrote:

kevlarcorolla wrote: Cool but I can't get how it could handle decently with an auto and a stick powering wheels with different ratios all at different times.

http://grassrootsmotorsports.com/forum/grm/twin-engined-cars-looking-at-you-ansonivan/32456/page1/

Not really sure what your trying to teach me,I stand by my 1st post.Its a dumb idea to combine an auto and a manual trans.

Twin engine cars like this aren't new. Car and Driver built a twin engine CRX way back in 1985. http://www.carlustblog.com/2008/02/car-lust--twin.html

irish44j wrote: GRM: Future issue: This thing vs. the Durocco for twin-engine supremacy!

durocco wins

Not really sure what you're trying to teach me,I stand by my 1st post.Its a dumb idea to combine an auto and a manual trans.

And how would you do it?

Two 5 speed shifters in the cabin that you had to negotiate?

carguy123 wrote:

Not really sure what you're trying to teach me,I stand by my 1st post.Its a dumb idea to combine an auto and a manual trans.

And how would you do it? Two 5 speed shifters in the cabin that you had to negotiate?

Fab a shift linkage that will operate both transmissions. Two manuals, or two automatics, would ultimately make more sense in my eyes.

Duct tape two shifters together side-by-side, duh.

I dont see why a manual and an auto is a bad idea at all.

kevlarcorolla wrote:

JoeyM wrote:

kevlarcorolla wrote: Cool but I can't get how it could handle decently with an auto and a stick powering wheels with different ratios all at different times.

http://grassrootsmotorsports.com/forum/grm/twin-engined-cars-looking-at-you-ansonivan/32456/page1/

Not really sure what your trying to teach me,I stand by my 1st post.Its a dumb idea to combine an auto and a manual trans.

I thought that was the thread where it was mentioned that neither the Durocco nor Nashco's $2009 AWD Fiero hybrid (Normal fiero in the back, electric S10 in the front) had any issues. Sorry if I pointed you to the wrong thread.

Fab a shift linkage that will operate both transmissions. Two manuals, or two automatics, would ultimately make more sense in my eyes.

In the LeMons series I'm not sure someone would take the time to do this. Sans a dual linkage I don't see anything wrong with a 5 speed and automatic.

Now with that said if they fight each other by the automatic shifting in odd places in a corner then I reserve the right to change my mind. But if you had a problem on a road course I could see that you could figure out which corners to put the auto into 2nd and leave it.

On an autocross course since you would hardly ever get out of 2nd on the auto just put it there and leave it.

carguy123 wrote:

Fab a shift linkage that will operate both transmissions. Two manuals, or two automatics, would ultimately make more sense in my eyes.

In the LeMons series I'm not sure someone would take the time to do this. Sans a dual linkage I don't see anything wrong with a 5 speed and automatic. Now with that said if they fight each other by the automatic shifting in odd places in a corner then I reserve the right to change my mind. But if you had a problem on a road course I could see that you could figure out which corners to put the auto into 2nd and leave it. On an autocross course since you would hardly ever get out of 2nd on the auto just put it there and leave it.

I would just be happier with the same drive ratio front and rear. It's not so much that I think using a combination of automatic and manual is bad. It's that I think having two like transmissions is probably better. I'm also not a fan of the automatic in the racing environment. If they'd had a manual in the rear, the rod knock the developed would have been a much shorter stop, but since they couldn't just drag an automatic around, they lost several hours.

I too thought you should have a matched set, but several articles I've read made me realize that it wasn't necessary. I was thinking more of drive ratios, but I don't see why that wouldn't apply to manual and automatic when it really simplifies the linkage issues.

I still think that a lower powered engine in the front could change the drive bias to more RWD which would make it corner better, wouldn't it?

Can't you just put an auto in neutral and drag it around that way?

carguy123 wrote:

Not really sure what you're trying to teach me,I stand by my 1st post.Its a dumb idea to combine an auto and a manual trans.

And how would you do it? Two 5 speed shifters in the cabin that you had to negotiate?

I wouldn't do it with 2 engines in the 1st place,too much added weight plain and simple.For dry track road racing awd isn't a huge advantage,with that mr2 a junk yard diy turbo set-up with the original engine would be easier,lighter,almost certainly handle/drive better and be faster and less likely to break stuff. Only advantage I see in endurance racing is if/when one engine fails you can at least continue with the other. You may have noticed my mid engine awd geo project,that makes far more sense for about the same amount of work.Much lighter,far better balanced both fore/aft and side to side with driver on board.I have 1 wire harness,1 battery,1 shifter and awd.

This is the real American way, to build redundancy into all flight components.

Hey guys, I keep stumbling across forums with threads to our car, the MRolla. Thanks for your interest.

To address a few questions I see here:

Transmission selection: An automatic in the rear was the easiest way to get the thing track ready and is very easy to drive. No fabrication required beyond welding another cable mount to the stock Corolla gas pedal. Just bolt up the automatic and mount a control lever. Driving control is fairly intuitive.

Ratio differences are you friend. Having the auto shift while the manual is under power does not interrupt acceleration. Vise versa is not true but the way we rigged the kickdown means the auto does not hunt gears during manual shifting. Pretty sweet. Some experiments with kick-down setting did prove to be a bit abrupt on the auto for some corners and conditions, but for the most part it's great.

There is a technical article here: here on our blog

There are some theoretical performance advantages to 2 engines vs 1 of equal HP. Mainly much of the engineering challenge of distributing power and traction to 4 wheels from one engine becomes unnecessary. If you have 2 engines with effective differentials and tires at both ends you are done.

As far as handling, yes there is a penalty if you mass is distributed like a barbell vs a ball. Fortunately we've used a an mid-engine car for the rear that had great mass distribution, and the whole car is pretty short. Total weight is 2800 pounds. Not bad for a 200 HP car. It is not a pig in corners.

How this translates to the track is quite effective. Compared to an MR2 the MRolla is not nearly so nimble, but is EXTREMELY forgiving. You can't spin this car. I took it off course on a sweeper at nearly 90 MPH and just kept driving until I was back on track. You can go in too hot, but other than that you can't screw up.

We have room for improvement in springs that could reduce roll, but I doubt corner speed and lap times would improve.

Our weakness is driving skill at this point. I want to get some good, trained drivers to see what sort of lap times we get. It feels like a top-10 Lemon to me.

You can follow us on farcebook if you like, or get more details on our blog:

http://www.facebook.com/TheMRolla

http://beater-car.blogspot.com/2011/05/mrolla.html

You sir, are VERY welcome here!

I promise you have nothing but adoring fanboys on this site!!

Great job!!

Awesome input! And super cool car!