How is it possible to mount a second engine to the rear end of a car? And how does the driver control two transmissions with one shifter? Does the advantage outweigh having a single, high-power engine?
- posted
18 years ago
How is it possible to mount a second engine to the rear end of a car? And how does the driver control two transmissions with one shifter? Does the advantage outweigh having a single, high-power engine?
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Yours is one of the strangest questions ever posted her. Here's an even stranger answer:
For the original poster, since you're contemplating something pretty strange, why not try the following instead: Get two cars, cut them in half (front and back) and weld both fronts together. Two engines, four wheel drive, four way steering. :)
We expect to see pictures when you're done. Remco
Curious wrote in news:Xns96C572377FC4Emrcuriousnowherenet@63.223.7.253:
Absolutely.
Chevrolet made a one-off Chevette back in the '80s that had two engines. Car and Driver reported on it in an article entitled "How to Scare Your Mother".
Citroen made those out of their 2CV years ago (it was sold in Africa and I think was called the "Sahara"). Renault made them out of their R5 (Le Car) as a rally homologation special.
If I can find my copies of Practical Classics that have these, I'll scan the articles and post them.
Transmission control with a single shifter is easy enough. Many, many vehicles have been made with rear linkages. I'd assume the shifter would be somewhat heavier to move, though.
The advantage is simple: Engine makes 100 hp. Car weighs 2,500 lbs. Each hp has to move 25 pounds. Now put in two engines. Car now has 200 hp, but only weighs 3,000 lbs. Each hp only has to move 15 lbs. That's a 40% increase in motive power.
The disadvantages are complexity, expense, and thirst.
of course you can. how much do you want to spend doing it? advantage of the weight of two engines, two transmissions, and the control elements? not much. better to go for a single power unit, single transmission and keep it as simple as possible.
i remmeber seeing a 'car challenge' program that had that as a challenge. 3 teams were given a thousand pounds (about $1800) to buy two cars and anything special, then they had 2 days to make the car you described, ready for a race with offroad, high speed, and handling areas, including those where 4wheel steering would be required to crab. Each car still had 2 drivers in it.
The winner used the front oend of a rover 800 vitesse (with a 200hp 2l turbo unit) and a fiat panda front end for the 'back'.Was a very interesting episode, 2 of the cars made it, one broke down before the end, but not far before 9it was smoething like a 8 mile course)
Someone did that to a Volkswagen Golf a number of years back. The car competed in the Pikes Peak run, and I believe it won its class. Can't find any references to it on the web, though.
Chrysler's done it. Check out the Jeep Hurricane concept vehicle.
"...Hurricane is not just HEMI®-equipped, but HEMI squared. There are two 5.7-liter HEMI engines in the vehicle: one in the front and one in the back. Both engines deliver 335 horsepower and 370 lb-ft of torque - a total of 670 hp and 740 lb-ft of torque."
Yeah, it also did a run on top gear, i think. Well, either top gear, or one of clarkson's videos.
Then there was also the dual engined Mercedies A-class cars that were given to Hakkenin and coulthard around 97-98 time.
Very cool! I'd love to see that one. There's a show here in the US where they do similar things called "Monster Garage" -- they can only cram so much in a 1 hour episode so it tends to be more drama than technique, but some of the thing they make are very interesting.
Why stop at two?
Yeah, its not really the same kind of show, since therse only one team in MG, theres 3 in the other one, and the start vehicle is chosen by the production company, and the parts buying is rigged. The british one is a hard limit (because UK tv companies are cheap) and the money you got it is. No new engines and high end parts for them. Its junkyard cars, and parts from the lcassified ads. makes for a more interesting show
Some friends and aquaintencies ahve been on Mgand at least one said that the end vehicle is heavily 'steered' towards. You don't really get much say in what the design will be. That was when he was on the delorian hovercraft ep (i think)
Dual drive systems are used quite a bit in industry. It is best to use servo controls with high resolution encoders for feedback for these types of systems.
absolutely! especially on larger equipment where transmission over distance is problematic. but on something like a racing car? especially a mid-engined one, you're just increasing weight & decreasing reliability. but then again, the "cool" factor gets the fans excited, so it's great for publicity.
4 - 4000 RPM direct drive servo's on a car frame, each with 200 lbs/ft or more of torque. Brushless with all digital drives, co-ordinated within 2 or 3 encoder pulses (5K pulses per rev min digital encoders) . No need for breaks, the drives are regenerative!
I'd pay to see that.
What the hell, half of the specs are right there. With a little money and a little time.... OK, maybe a LOT of money and time....
Some friendly people over at rec.autos.makers.vw.watercooled suggested
The Car and Driver dual engine CRX is still alive and kicking. Great, simple project car that worked out much better than anyone anticipated.
anyone got any pix?
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