[Revvmaster]

Originally Posted by aveek

@Revv: I meant 2 petrol engines both running simultaniuosly, not 2 engines, with alternate power generation. As I'm not too sure if the Mentioned cars have the above configuration, thje Prius and other hybrid cars are definitely out, as they run altetrnate engines, right...??

The mentioned ones have two engines running simultaneously. Like you mentioned, you wanted two engines of same capacity and power. These cars are called Bimoto or Twin-Motor engined cars. Motor Engine= Petrol/Diesel engine. These cars have two engines, one in the front and the other in the rear in most cases or are two engines lined together. In some cases they have the front engine running the front wheels and the rear the rear wheels.

The biggest challenge IMO is developing a gearbox that can suitably link itself to two engines. It is nothing short of an engineering challenge if you may ask.

Prius and other hybrid cars have a petrol engine linked to an electric motor. In that case they are out.

Revv

[BuRnT RuBbEr]

Originally Posted by Revvmaster

The biggest challenge IMO is developing a gearbox that can suitably link itself to two engines. It is nothing short of an engineering challenge if you may ask.


Revv

not an easy task...even on paper..what to talk of live car..with a human driving it.....

[Harrie]

Well I did toy around with this idea for a while. I was tinkering around with a smashed fiat premier padmini and a M800. Then I thought why not put the M800 rngine complete with gearbox for the front wheels and the fiat engine for the rear wheels.

All i wanted was some fun and show off. But then for that i had to relocate the fiat engine backwards. not between the rear wheels but slightly backwards as this would be easier for me. Then make custom engine mounts, change front suspension and then put the M800 tranny.

I was doing all the planning work and that is when i realised that the fiat chassis no matter what i do will never be able to take all this. and not to mention the cost involved.

finally scrapped the project. but who the heck cares? I can go about telling well i did try to make a car with two engines...

[Psycho]

Originally Posted by aveek

@Psycho: The torque and air-flow and everything is pretty much monitored by a 32-bit comp. chip anyway, na? I'm sure that people wqouldnt find it too hard to map an ECU that controls all this as well.

@Shravan: lets say an engine wighs 400kg and blts out 500BHP. So then 2 engines = 800KG vs. 1000BHP. Id say thats fast enough... wouldnt you...?? As far as I can see, the Power to Weight ration can only go own, uless the engines are de-tuned...

@iceman: so why cant we have the ECU figure that one out...?? As it is, the Enzo, Carrara GT, and every other 'modern supercar' have these chips in em... so, why not have a nice computer RAM type chip instead, and sort all these problems out...??

Well for starters lets answer these 3 questions:
1) Airflow is monitored but it needs to be even for equal power output. Mapping an ECU would be easy if it was one ECU here you are trying to link 2 engines with 2 ECU's also you need to get the cylinder firing orders on the 2 engines to be synchronised the only way to do that is to have the 2 engines linked this would also help increase the torque on the engines.

2) 400kg - 500bhp = 1250 bhp / tonne, also 800kg - 1000bhp = 1250 bhp / tonne the only difference that you have missed are the torque characteristics...

3) As Ice said and I pointed out in (1) the two engines need to have their firing order sync'd and also a wheelspin can turn the car... to avoid this you would need traction control...

Suggest that you relook at the idea as there is no way you can link existing transverse mounted engines until and unless you build a custom tranny setup ... Also an ECU is not a RAM based system it is a processor and it uses the stored MAP's in the EEPROM chip for the calculations.

[vivekiny2k]

how about jeep hurricane?

doesn't it fit in the specifications?
well, not sure whether it's in market yet.

http://auto.howstuffworks.com/jeep-hurricane.htm

[shravan316]

Originally Posted by aveek

@Shravan: lets say an engine wighs 400kg and blts out 500BHP. So then 2 engines = 800KG vs. 1000BHP. Id say thats fast enough... wouldnt you...?? As far as I can see, the Power to Weight ration can only go own, uless the engines are de-tuned...

Agreed with that, but, say u have an engine which puts out 500bhp n weighs 400kg... lets suppose another engine is put in its place so as to pump out 1000bhp.. the weight will not be 800 kg. will it?(provided you use the same composition of materials as used in the 500bhp,400 kg engine) it'll definitely be lesser.. So the power to weight ratio will increase. What say??

[aveek]

@Shravan: ok, you got me there. Either that or i'm one confused soul.

@Psycho: It was just a sugegstion, as I'm not exactly a graduate student with ECUs an all,it was mostly assumed. Thank you for the 'enlightenment' ;-)

@Harrie: Damn yuo!! Everyones beaten me to tthe idea!!! NOOOO!!!! Ho much did the whole thing set you back by?? And do you have any drawings of plans or such...? :-p

@Revv: Right. I didn't kow those ran wth bith engines together. Pretty neat.

@everyone in general, with focus on Revvs last comment: If tthese guys have already one it, (and there seem to be quite a few with the provided list by Revv...) and they seem to have worked(as in some cases there were two, hence suggesting that the 1st did work, even if only marginally) why doesn't anyone look up those and solve the transmission problems, or the ECU mapping, or any other problems that do come up..??

[adilshah]

just a query...i had designed a simple remote controlled car fitted with 4 motors...each motor going to a wheel...the motors were 500 rpm motors...i dont think putting a 500 rpm motor in the front and a 500 rpm motor at the back gave me 1000 rpm. all i got was very nice torque.
so in effect if u have 2 engines i doubt you will get x+y hp. you will definitely get better torque but hardly an increase in horse power.

[v1p3r]

How do you equate rpm with torque, or bhp? Both can be split, but you can hardly split rpm between wheels, can you?

[speed0mania]

hey guys me and a friend had a discussion on this , as a crazy friend cracked a 'joke' about fitting an m800 engine in the rear of an accent tornado1.6 !! so i argued that it would not be feasable at all, as the rpm at any point would be different and it would cause a wheel spin!! but my friend argued that it could be possible as the other engine would provide extra tourque . well our argument went on literally all night ! but what we realised from our 7 hr debate was that he was seeing the aspect of extra torque while i was looking at it from the point of view of rpm and velocity!!! i still think its unfeasable!!! and it has been over three months since i've been thinking about this and the following are my conclusions corect me if i'm wrong . all these are assuming that all the technical barriers discussed about the transmission etc. arer overcome:-
-the rpm of all tires have to be the same at all times.
-the acceleration off all wheels should be the same.
-there must be a traction control to avoid wheelspins at any cost.
-(i dont know how to fram this one)torque has to be supplied in the form of impulses(thats what an engine does right !! ) )

because if the two are not tuned perfect;y in sync then it could lead to power loss rather than gain right???

[theMAG]

Before anyone gets excited thinking I'm adding another engine to my Swift - I'm not, I was curious to understand the various nuances of having 2 engines on an Indian car of any make.

1. Which cars would qualify for such a project

2. What should the engines' stats be - assuming a 1-1.5 ton car

3. Can each engine be of a different o/p level

4. Determination of engine-drive: front-engine drives front wheels etc., or AWD

5. Projected driving characteristics/dynamics of this twin engined car

6. Rough ETD assuming parts/chassis/engines availability

7. What would be the (high-level) technical roadblocks


This car will be solely performance inclined



Mucho gracias.

[gd1418]

Oh God, it is like having a Linux & Xp on the same machine.. How exciting that we would have two engines - one petrol & other diesel. Switch to petrol engine while driving within the city. While on highway, just toggle the switch and the diesel powerplant takes over..

Originally Posted by theMAG

Before anyone gets excited thinking I'm adding another engine to my Swift - I'm not, I was curious to understand the various nuances of having 2 engines on an Indian car of any make.

1. Which cars would qualify for such a project

2. What should the engines' stats be - assuming a 1-1.5 ton car

3. Can each engine be of a different o/p level

4. Determination of engine-drive: front-engine drives front wheels etc., or AWD

5. Projected driving characteristics/dynamics of this twin engined car

6. Rough ETD assuming parts/chassis/engines availability

7. What would be the (high-level) technical roadblocks



Mucho gracias.

[v1p3r]

Well, the normal (if you can use that word) way is to have one engine driving the front and the other driving the rear. Gearshifts are linked centrally, as are throttles. But they are two separate powertrains, in essence.

It's been done to quite a few cars. Beetles, Audi TTs, to name a few production ones. Then there are so many specials and custom cars...

[CaliforniaKnight]

Mercedes had also made a similar project on their A class cars which was custom built for their F1 drivers , Mika Hakinnen and David coulthard if I am not mistaken..

[sbasak]

See Jeep Hurricane here
Howstuffworks "How the Jeep Hurricane Works"

For barebone project, probably Mahindra open top jeep will be best