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PostPosted: October 24, 2007, 12:58 pm 
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Location: The Rock(Newfoundland)
Any reason why an engine powering the front wheels and an engine powering the rear wheels would not work?


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PostPosted: October 24, 2007, 1:20 pm 
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It will work, but you have to have them perfectly timed to run the same RPM, torque, and throttle response. It has been done before many times, but the weight penalty and PITA factor make it an idea that doesn't make a lot of sense. Go for it though, it will drive like crazy and handle well if you get it balanced.

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PostPosted: October 24, 2007, 2:24 pm 
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I was worried about something strange such as axle windup where the front was traveling farther than the rear when going around a corner or something like that.

BTW-megasquirt-The car that won Targa Newfoundland overall this year was a BMW2002 sporting my friends old megasquirt system.My friend also currently has a 320i that he turbo'd and is running another megasquirt system.


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PostPosted: October 24, 2007, 2:52 pm 
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Axle wind up can be a problem with any car that has an axle that has no differential ability (spool) such as a drag racing car. As long as the differential can allow different wheel speeds, then there is no problem. Also, think of a truck in 4WD as having axle wind up issues. When you turn the front axle is taking a different path than the rear axle and since the transfer case doesn't allow this. With separate engines you wouldn't have this issue. The biggest issue would be with getting the two engines to go the same speed all the time. You don't want one engine to be dragging or pushing the other one. They would have to be balanced in order to work correctly.

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Build sold to a new loving home. May start another one when I have more time to devote to it. For now I play with my boat, Datsun 240Z, and GS700 motorcycle.


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PostPosted: October 24, 2007, 2:57 pm 
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was planning on doing this with my volkswagen golf a while back, has been done sucessfully by several tuning shops as well.

Imagine dual 400hp supercharged vr6's in a golf shaped package.

very cool and very fast

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PostPosted: October 24, 2007, 3:12 pm 
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The 2002 Sport Compact Car Ultimate Street Car Challenge had a Hyundai Tiburon with 2 turbo engines, each with 300 hp, each driving 2 wheels, and each with their own automatic transmission. As I recall, they were surprised that it was not as unruly as they had expected. The best part was when the cars had a burnout contest. The Hyundai driver put one transmission in reverse, one in drive, and floored it. :lol:


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PostPosted: October 24, 2007, 3:50 pm 
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They work just fine, in a straight line at least. The power from the two engines adds together. If you have a 500hp engine at one end, and 100hp at the other, it works just fine, really.

The problem is when you go around corner with any sort of throttle. NOW any unbalance whatsoever will cause under or oversteer. This is the real reason why it's not a viable car. It's nearly impossible to make sure there's no unbalance. Lord know how screwed up mid-corner handling would be with two turbo engines, what with one coming on boost before the other one.

Anyone who's ever cornered a car at the limit of adhesion knows that ANY unbalance will mess up the handling (at best) or put the car off the road at worst.

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PostPosted: October 24, 2007, 11:59 pm 
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What about using an AWD running gear from a subaru or bmw, then attaching two bike engines to the same tranny? Use a chain and sprocket to connect the two together, and machine an adadtor to connect a central sprocket to the trans. Or skip the trans and go straight to the diff.


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PostPosted: October 26, 2007, 5:50 pm 
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the 2 engine concept has been tried in both a Seven (I believe both driving the rear wheels), and in an Ultima GTR (both engines behind the driver, one driving rear wheels, one driving front wheels)


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PostPosted: October 26, 2007, 5:51 pm 
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http://www.zcars.org.uk/ultima/index.htm


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PostPosted: October 27, 2007, 5:22 pm 
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A friend of a friend had a Toyota Corola with twin engines. He competed in ice racing in Ontario and did quite well from what my buddy says. He used two identical Corola engines with auto transmissions. From what I heard he had some trouble getting the throttles synced up but after that it was pretty competitive. Of course ice is a little more forgiving to axle wrap than pavement.


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PostPosted: January 30, 2008, 5:07 pm 
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If the engines were controlled by one electronic throttle and one control unit I could see it being feasible. I wouldnt do any type of competitive manuevers without having both engines balanced and blueprinted to each other. I dont think it would be very locost to have it high performance.

The two enging thing always makes me think of this video:
http://www.youtube.com/watch?v=hoGtquXtv14
They might just have two steering wheels etc... but funny.


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PostPosted: January 31, 2008, 7:02 am 
paulneartarga wrote:
Any reason why an engine powering the front wheels and an engine powering the rear wheels would not work?


I remember seeing a factory built citroen 2 CV with the same engine and transmission fore and aft. This was a sort of poor parent all wheel drive.
From a backyard building angle this type of arrangement is a cheap short cut to modern all wheel drives like Subarus. From a weight and mechanical stand point the only advantage of the two engine arrangement is that like a boat or an airplane if you loose an engine you can make it home on the other one. Two transmissions and diff add to the weight though.

The Citroen below featured (1957) two flat twin engines two transmissions and one hydraulic clutch pedal.

Philippe


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PostPosted: February 1, 2008, 4:45 am 
I am seriously considering AWD for Shagnasty. For autox I believe there 300lb penalty but I believe this would be a non issue with more than 500 hp and 4 315 35 17s. I believe you could get on it at will on the course, it would be fun till outlawed.

This could be accomplished with a Windsor by converting the T5 to a transfer case using the tailhousing from a Jeep T5, just got one, It would require a modified WC mainshaft. At this point I'm thinking a GM 203 nus range box ced with apiece of plate. The front diff would be an aluminum Mk VIII with Torsen T22s front and rear. I'm not sure of the front knuckles, 87/88 Jeep D30 knuckles could be used along with the CV from a ZJ, this would be a bit heavy but should work and the Mustng PBRs could be easily adapted. Possibly C5 knuckles could be used.

Along the line of twin engines search for twini mini this was done with the mini and discontinued after a track crash nearly killed Cooper.


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PostPosted: February 2, 2008, 11:58 am 
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Top Gear covered a twin engine audi tt. There's a video on youtube.

http://youtube.com/watch?v=W0kN_4YdhsI

Peter


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