Chi_San

I've seen video of small light cars with small, medium, and even a few large V8's in them, or even a FB/SA with a NA 20B in it... In most of the videos, the vehicle in question is always extremely fast... But, they have traction problems in usually first, second, and third gears...

I've been thinking about this for a while now. Would it be possible to swap a complete AWD drivetrain into a RX-7 chassis?

A Subaru STi 6 Speed MT can take 700+ hp and 700+ lb-ft of torque, perfect for a turbo V6 or V8...

I know it would add a bunch of weight to the car, but having an AWD RX-7 would be like... A dream. The question is, is it a pipe dream, or not?

Crash Test Joey

iTrader: (1)

ANYTHING is possible if you really want it done. Race cars are built from a tube chassis up, and all cars started as a mental picture in the back of someone's mind.

The questions you need to ask are "How much do you want to spend?" and "How much time have you got?"

For AWD the simplest way would probably be to transplant the drivetrain from another car. Take the Subaru you referenced, for example. An RX7 may have hood clearance problems or something like that, but basically designing mounting points for the suspension and drivetrain you're adding is the hard part. After that, it's a matter of shortening/lengthening or otherwise modifying everything else to make it fit.

I don't mean to make it sound simple, because I know it would be no easy thing to do. But if the knuckleheads on American Hot Rod and Monster Garage can build the wacky **** they do, surely someone with an engineering degree could figure out something like this.

Chi_San

True... Looks like I'm going to start taking welding instruction from my neighbor again.

The Subaru transmission came to mind because the front diff is part of the housing. Just less to deal with... Fewer things that need to be mounted seperatly to the bottom of the car.

Since the Subaru transmission sits kinda back in the chassis, it may be a tight fit getting it all hooked up right. The shift **** would be like... In the back seat. :p We'll see, though...

Next, I need to find a wrecked WRX or STi and pull the transmission. Paying $600 for a RX-7 then putting down $6,000 for just a STi gearbox, plus rear diff, axles, hubs, brakes... Yeah, might try something a little less expensive first.

Nihilanthic

Youd be spending a TON of money on this and youre going to need to know your ****.

What Im curious about, though, is why youre going to do this? Youre going to add a ton of weight and AWD really wont give that much of a gain over a well setup FR Chassis. This *IS* an RX-7 afterall... is this some sort of one off for rally or just to make something really crazy?

I also dont know how youd do the front suspension to power the front wheels... you might have to fabricate a lot of stuff for that. For the rear just a new DS from the rear to the transmission would be sufficient, most likely.

Im not trying to **** in your cheerios here but you might as well go make a full one off tube chassis car, lol.

If you want a light kickass AWD car... strip an old imprezza or GSX eclipse or something. Cheaper and easier.

If you want to swap a RX-7, there are the obvious v8 swaps, the SR20 swaps, RB or JZ series swaps if you want a straight 6 and the one Im gonna do, the ford "lima" 2.3 turbo.

Crash Test Joey

iTrader: (1)

I'd try measuring to see where everything sits in the car you want to use as a donor. YOu may find out that your concern about shifter placement is right on, or that it is not a big deal at all. A T-56 behind a V8 sits pretty far back, and an RX7 isn't really any smaller than a Subaru or a DSM.

Fabrication would be the biggest expense, and for what you would end up with (probably the world's only AWD RX7?) you might find it worth doing just for the pride.

saltyslug

how about just getting a subaru wrx and putting a 3 rotor in it. alot easier and alot more fun with the 3 rotor.n I think the aussies have adapters in the works.

Crash Test Joey

iTrader: (1)

Because a WRX looks like it ran into the back of a truck?

Chi_San

One reason I don't get an old Impreza or Eclipse is because, well, you can't stick a V8 in an Impreza, and finding an AWD Eclipse around here is... Well, I've never seen an AWD Eclipse.

Not to mention, it would be neat being able to say I have the only AWD RX-7 in existance. :p

turbogarrett

iTrader: (1)

Some guy on ls1tech was building a turbo lsx rwd wrx, I haven't checked the status for awhile though. Anything can be done, but an awd rx7 will require a lot more than basic welding skills.

dubulup

rod millen made an AWD FC...he's got bank though

Chi_San

Good point...

RWD WRX's are pretty easy to do, indeed, there are a few on the Subaru forum. It involves welding the center diff up then pulling the front drive shafts. Or, simply find an FD transmission and, believe it or not, it'll bolt right up. Mounting points for the tranny casing are in the same spots, engine bolts right to the tranny, just need a rear diff and a slightly longer drive shaft going to the rear diff.

Rxmfn7

iTrader: (4)

Not to sound condesending, but have you ever driven/raced an AWD car? Im not trying to say I am an expert, but Ive had my fair share of experience with a few AWD DSMs, and I really dont care for the AWD thing. Is it a bit easier to control, maybe, but the whole feel of it just sucks to me. It pushes too much like a FWD car.

digitalsolo

iTrader: (2)

Fix the suspenion then. A properly tuned AWD car drives GREAT. About as good as a car will handle without going "maximum effort".

fcdrifter13

both the ideas have already been done. And there was also a v8 put into a impreza. As the saying goes anything is possible, but the thing they dont tell you is it will cost out the ***.

owen is fat

properly widebodied high powered RX7's dont have a huge problem with traction... its all about running 315's or 335's out back and having appropriate gearing out back for your type of racing.
335's on a tripoint widebody FC -






OH YEAHHHHHHHH!

Nihilanthic

That wing does that Green FC use? I see the brackets on the rear!

And wtfs with the camber, theres hardly any wear on the outside edge of that wheel... unless he just hasn't dropped the hammer yet in a corner.

Chi_San

O_O I sure hope so! Otherwise, someone is going ot have to explain why my Subaru is only FWD or RWD!!!

There is a specific technique to AWD, like RWD and FWD when it comes to driving fast. having experience driving AWD for a few years now...

One other reason I would perfer AWD over RWD is because I do often drive off road, in rather slippery conditions (read: up steep mountains on hard packed snow), so AWD would be beneficial. Though, I can drive RWD just about as well as AWD, just not offroad yet.

I'm going to get the SA I've had my eye on for a while, and if the engine and transmission are okay, I'm probably going to upgrade the suspension and leave it at that, otherwise, I'll end up with either an H6 or V6 turbo RWD swap going on.

The Mitsubishi Evo uses a rather advanced AWD system, if it's equipped with a Yaw Controller, during cornering the front and rear diffs can transfer power from the left or right wheels, and the center diff transfers power from the front or rear wheels... An evo on a long corner can literelly be sending 100% of the engine power to one rear wheel. Not that I want to do something that complicated, it would be heavy as a Viper. there are also AWD systems for Subaru 5 and 6 speed manual transmissions where you can transfer powre more to the rear wheels, or in some cases, convert the car in a short tim from AWD to RWD, and back.

I think I'll focus on one swap at a time, this was just more of a feeler to see how difficult it would really be...

Oh, and FYI, a stock subaru transmission hooked up to a V8 would have some oversteer issues... Especially if it's an NA beast. :p Wouldn't be quite as bad as RWD, but it would still have issues...

Nihilanthic

The EVO in the USA doesnt have a computer, it just has a clutch pack in the rear and an open front diff unless its an RS - unless they changed it.

Also, Viper is 3300, Evo is 3200... if the viper has a lightweight and you weigh a lot you oculd easily weigh as much as the viper with the driver. hah.

Chi_San

I'd still take the Evo over the viper. :p

I checked out the SA that I've had my eye on... The tags on the plates expired in 1997, which means, unless someone owned it and lived out in the couty where I&M doesn't exist, the car literelly hasn't been driven, or even started since 1997. O_O