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will a subaru engine run backwards...


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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.

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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

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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.

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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

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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.
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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!!!

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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

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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.

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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
Thats 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 :P

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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......

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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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