November 18, 200421 yr I have been meaning to ask this ? Depends on which one and what you mean by "backwards". Short answer is no. Medium answer is: Anything is possible with enough money, time, effort, and money. Wouldn't want to run an engine with timing-belts (or chain) backwards, as tensioners are on the wrong side of the "pull". EA81 should do OK on this score. Oil pump and water pump would be forced backwards... not a good thing. You would have to get camshafts that were ground as mirror images of existing grind (otherwise, exhausts would try to act like intake, and vice versa). PITA.
November 18, 200421 yr short question. Why? i mean, do you want it like vw style or as in backwards backwars like northwet just said? if you mean backwards backwards, what on earth could be the benifit? so you could go 100 miles per hour backwards?
November 18, 200421 yr Author I was just thinking the ea81 being timing gear, as in the brat it seems to not want to hold on compression when the rear is pointed downhill, would there be the possibility of it running in reverse rotation? a diesel engine will run in reverse rotation if you slam into sometning, dock, while in reverse
November 18, 200421 yr I was just thinking the ea81 being timing gear, as in the brat it seems to not want to hold on compression when the rear is pointed downhill, would there be the possibility of it running in reverse rotation? a diesel engine will run in reverse rotation if you slam into sometning, dock, while in reverse Common occurence in detroit iron, pre-emission and early emission eras, for the engine to "run on" after the ignition was turned off. VERY common for it to run backwards, dieseling off of the excess gas in the exhaust stream. So if this is what you are talking about, then yes, it is possible, especially if the mixture is set rich, the idle is high, etc.
November 18, 200421 yr The engine turns the right way, its the trans thats backward. Not many choices, I can only think of two off hand, both German... VW Vanagon Syncro and the Porsche 911 AWD... good luck finding one and bring your check book. I think its been done with a modified Porsche 5 speed 2WD box fitted with a custom secondary shaft. I'm right there with you though, I'd love to put a rear engine 4WD set up in my fiberglass dune buggy, I've got a couple of ideas but they need more development time. Gary
November 18, 200421 yr I was just thinking the ea81 being timing gear, as in the brat it seems to not want to hold on compression when the rear is pointed downhill, would there be the possibility of it running in reverse rotation? a diesel engine will run in reverse rotation if you slam into sometning, dock, while in reverse And a two-stroke diesel should have little problem running backwards... at least until any pressure-lube system it has causes the engine to fail.
November 18, 200421 yr The engine turns the right way, its the trans thats backward. Not many choices, I can only think of two off hand, both German... VW Vanagon Syncro and the Porsche 911 AWD... good luck finding one and bring your check book. I think its been done with a modified Porsche 5 speed 2WD box fitted with a custom secondary shaft. I'm right there with you though, I'd love to put a rear engine 4WD set up in my fiberglass dune buggy, I've got a couple of ideas but they need more development time. Gary Sort of off-topic now, I think, but... Turn the tranny upside down. I knew an auto-x'er who had a Lola chassis, Buick Al 215-V8, and an upside down 911 tranny (mid-engine with rear-engine tranny in this case, but same concept). FAASSTTT!!!
November 18, 200421 yr If you turn the impeller around on the oil and water pump and made a camshaft that was a mirror image of the stock one, and maybe the firing order on the disty, then it would in reverse no problem!
November 18, 200421 yr What about a gearbox or driveshaft adaptor that simply reverses its direction, im sure ive seen gearbox designed for tractor use which is designed for changing the direction of the PTO.
November 18, 200421 yr well you guys don't remember the Corvair much huh the motor ran backwards from what we are used to for the flat 4's/6's and back in the day for to mate it to a vw tranny is to get the cam replaced with an aftermarket one to make it work right for the tranny as for reversed tranny's the only one I can think of if you adapt it to another vehichle is the early VW bus tranny's cause of they used reduction boxes so the diff was sat up to run reverse and to fix that all you do is rotate the diff in the case 180 deg by unbolting both plates on the sides of the tranny and just flip flopping them around to make it rotate fowards in a bug or squareback
November 18, 200421 yr The Merkur XR4tI had, IIRC, a reversed engine. It was FWD only in north america, but I believe there were some Euopean examples to be had with AWD...
November 18, 200421 yr Maybe just turn the differential upside down. In the 1930's Chrysler products it was easy to goof up and install upside down. Viola! 1 speed forward, 3 speeds in reverse. Ray Mac.
November 19, 200421 yr Just remembered--flipping differential would only work with a RWD, not with transaxle. Duhhhhh---- Ray Mac.
November 19, 200421 yr flipping diffs in some certain transaxles is possible and has been done for many reasons in fact I am always curious if it can be done with a subie tranny so you could actualy make a AWD bug or something like that with all subie parts
November 19, 200421 yr The Merkur XR4tI had, IIRC, a reversed engine. It was FWD only in north america, but I believe there were some Euopean examples to be had with AWD... Ahhh yes, the Ford Sierra Cosworth...
November 19, 200421 yr flipping diffs in some certain transaxles is possible and has been done for many reasons in fact I am always curious if it can be done with a subie tranny so you could actualy make a AWD bug or something like that with all subie parts Nope - the hypoid/offset pinion wont mesh with the crownwheel when you flip the crownwheel over.
November 19, 200421 yr flipping diffs in some certain transaxles is possible and has been done for many reasons in fact I am always curious if it can be done with a subie tranny so you could actualy make a AWD bug or something like that with all subie partsThats my dream, but no go with the Subie tranns. The final drive is of the hypoid type (not the simpler spiral bevel used in the VW trans), and it cannot be flipped. Gary Edit: What Mikie said
November 20, 200421 yr Any engine, can be built to run backwards. You need a reverse ground camshaft, and a reverse wound starter motor. Kinda fuzzy on all the details involved, but thinking plug wires may have to be reversed also. Don't 'member of-hand who's magazine it was in, but you could order the stuff to do a R'd Chevy engine. Thinking it had to do with stuffing one in a VW.... Have to run a manual tranny though, as Auto's don't run to good being turned backwards. Pump don't do backwards real well, regardless of make. Need pump to pump fluid, no do that running backwards......
November 20, 200421 yr lots of rock crawlers use flipped differentials with recut gears to make them not eat themself's from continuos reverse rotation the advantage of a flipped diff in a offroad setup up is the pinion is up higher so on large lifts the drive line angle is alot less severe also a little bit more ground clearance the main problems with flipped diff's is lubrication has to be reworked as well granted when i think flipped diff i also think the whole axle is upside down
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