Daydreaming about bigly lifting my Forester

So my daily driver is this 2001 Subaru Forester S with nearly 200k miles on it. I love it dearly and I never plan on parting with it. It has tons of character that most people would not find cool, but I still really like it. The exterior is hail damaged. The paint has faded into a very unique mix of cranberry red and sunset orange. But it does have a lot of good things going for it. It's in great mechanical condition, drives excellently, and is truly rust free! The interior is also in remarkably good shape for a car with 200k miles. Here's my Subaru at the top of Ophir Pass:

One thing that's always been nagging in the back of my head is the idea of a Forester that's more focused on off road duty. Something that could bomb down gravel roads and fire roads, be more capable on rugged and unimproved roads, and even do some light crawling. I've always been a fan of off road racing and love the look and performance of the trophy trucks and prerunners. I've wanted a little bit of prerunner flair and performance for my Subaru.

My generation of Forester is actually pretty capable off road from the factory with its decent ground clearance, all wheel drive, and rear (weak, but functional) LSD. However, there are quite a few obstacles it has with harder terrain. First of all the approach and departure angles are terrible with its bumpers sticking way out past the tires. Second, it really needs a few more inches of clearance to go along with the approach and departure angles. Third, and in my opinion is the biggest weakness of a mostly stock offroading Forester, is the tire clearance. These cars come from the factory with a tire a tire size that works out to about 26" tall. I have installed tires that are only one profile size taller, 27" tall, and it's already at the limit of clearance. The tire is about an 1/8" away from the strut body on the side and about 1/4" away from the spring perch above. Finally, the amount of travel is not enough. From what I've read it's about 5.5" front and 8.8" in the rear.

This is where the daydreaming comes in. And before I express my crackpot ideas I want to state that everything I list I believe to be totally doable with enough time and money. I have a degree in mechanical engineering and work at an aerospace machine shop that allows me to machine whatever I want, so even things like custom aluminum uprights are not out of the question. I also want to state that everything on this theoretical build must function and be the best way available to perform a task. No goofy junk and hacks here like subframe spacers that only lift the body but not the major hard parts.

I'm a firm believer that a vehicle should be designed around its tires. Everything just seems to perform better when that's the case. The largest tires I've ever heard of anybody running on a subaru is around 30". I think a 32-33" tire would be the largest I would want to go. This alone would give 2-3" more ground clearance. The gearing would be horrendous though. And everything beyond 33" gets to be obscenely heavy. A 32 or 33 would be tall enough and tough enough for any sane obstacle (and make the jeepers take you seriously ) I think.

Now that we have a tire picked the first obstacle in fitting them is the fenders. These cars really don't have fenders that were intended for this. I'm not opposed to cutting bumpers but I don't want to cut into the fenders or unibody structure just to fit larger tires. And If I built some custom fiberglass fenders then there's really no limit to what will fit on the front. From some really basic measurements, to fit a 33" tire the front wheels would have to move about 3" forward and the rears would also have to move back by about the same amount. At it's most basic, this can be fixed with a saw and a welder and modifying the oem suspension parts. You could probably be just fine with the oem pickup points. Then you just cut up the bumpers to fit, or what I'd like to do is build some cool looking prerunner style tube bumpers.

So now that we have wheels and tires that fit the next step is the lifting and boosting the suspension travel. The true limit to Subaru suspension travel and lift is extreme CV joint angles. A lot of the commercially available lift kits get around this by doing subframe spacers between the body, basically lifting without changing any of the suspension or drivetrain geometry. The camber change with struts start to become pretty extreme with long travel suspension too. My idea is to either find longer axle shafts or cut and lengthen stock axles. To go along with this we can also move the uprights out by the same amount. Longer axles mean less angular change for any given amount of suspension, and if we're sticking with factory style suspension, less camber change. I'd be happy to have 10-12" of suspension travel but I wouldn't turn away more if I could get it. I would also like to move away from strut suspension but that opens up a whole mess of other complications. I don't like the stiction and binding that go along with struts. I believe the off road suspension action and suppleness would be greatly improved by ditching struts.

Converting to double wish bone or similar type system is very intriguing to me. Particularly for correcting and redesigning the steering geometry to suit the larger tires. But that likely require redesigned uprights. And while I'm at it I may well design the uprights to accept Subaru's much easier to change bolt on wheel bearings. The list never ends...

TLDR; here's some pics of lifted foresters:

This one has a huge subframe lift, which I'm opposed to. Look how low all the important bits hang down.

Hey, hey, pretty early in the season on Ophir!  Where are you located?

Biggest problem I've had with my (newer) forester is punctures, very limited tire choice in the stock sizes of later models (225/60-17 means the only real all terrains are Yoko Geolandar AT-S, and I've had a couple punctures on graded gravel roads from little annoying sharp golf-ball sized rocks, just driving in and out of my subdivision (7 miles of gravel at 9000 feet).  BFG make a larger tire in their excellent AT, but it's a godawfully tight fit on a stock Subie.  So I use my 2001 TRD Tacoma for exploring the San Juans.

That was in March! I'm in northeastern Oklahoma. We have toms of beautiful gravel roads around here that I'd love to drive on but the combination of small tires and street oriented suspension feels pretty rough. I'd love to have my Subaru built enough that it could tackle any backcountry road out there,

Moving the subframes down to preserve geometry really is the proper way to do things. That's how the Forester gets taller than the Impreza in the first place. Well, that and the longer shocks and the rest of the factory bits that make it work. Any of the popular rally struts, and you don't have to go all the way to DMS or something like that, should get you a car capable of going to gravel roads WAY faster than any sane person would in a car without a cage. Gearing with big tires is a significant issue. Slammo on these forums is running a tire tall enough to require cutting of the fenders, but not as big as a 30, and the car already feels compromised from a gearing standpoint. 

mazdeuce - Seth said:

Moving the subframes down to preserve geometry really is the proper way to do things. That's how the Forester gets taller than the Impreza in the first place. Well, that and the longer shocks and the rest of the factory bits that make it work. Any of the popular rally struts, and you don't have to go all the way to DMS or something like that, should get you a car capable of going to gravel roads WAY faster than any sane person would in a car without a cage. Gearing with big tires is a significant issue. Slammo on these forums is running a tire tall enough to require cutting of the fenders, but not as big as a 30, and the car already feels compromised from a gearing standpoint. 

I agree completely on the gearing point. It's honestly one of the biggest potential showstoppers for this idea. My car is already slow enough with near factory size tires and gets mediocre fuel economy. And it will only get worse with even larger tires. The rear r160 diff has been around go so long that I wouldn't be surprised if some other car's ring and pinion with a higher numerical ratio could be installed. But the front diff is a giant mystery box. I have no idea what's available for that.

We'll just have to agree to disagree on the the subframe spacing topic. In my opinion, there are better ways to it than that. But I will concede that they can be fine for some people's uses. My biggest been with them, for their sole purpose of lifting the vehicle and getting more ground clearance, they only do haha of what they need. Sure, they improve approach and departure angles to tempt you into driving over larger obstacles, but all the important parts like the engine, trans, diff, suspension, and subframes stay the same height off the ground.

I am pretty cavalier about changing suspension geometry around. I think it's one of those things where once you know the rules (ie have a firm understanding of how each piece interacts, and the positive and negative outcomes of the changes) then you can break them. And the number one rule of suspension, especially on an oem setup, is everything is a compromise! Their goals may be a lot different than mine.

If you want to go to a double a-arm up front, at that point you're probably making a totally different subframe anyway so basically just go from scratch.  At that point I'd pick a different steering knuckle/upright and, since you're considering different axles anyway, use the outer stub and CV from whatever the upright is off of.  Then have the axle shafts made with the correct length and splines at either end.

At the rear, I think you can get a pretty good amount of travel out of the multilink.  If you really want a ton of travel though, the answer is probably going to be something you fab up, either bigass a-arms to match your front end, or a live axle with a 4-link like what trophy trucks/prerunners use. 

Some inspiration in the form of another vehicle this treatment was applied to:  

Serious question:

How much more painfully slow do they become with those big monster tires on it?

In reply to z31maniac :

I would imagine somewhere between "stock aircooled VW" and "golf cart" 

In reply to z31maniac :

Driving Slammo's lifted Impreza made me ask "is something broken?' It's sort of the inverse of a lowered track car with the same end result. It's worse in 99% of driving to be awesome that other 1%. It was a riot on sketchy rutted washed out hills and mud though.

I had a lightly lifted WRX wagon as a daily driver for a few years.

Was nice to slam into potholes and stuff and not worry.

Got crappy MPG.  

Overall was fun but gotta agree with above posts, anything that functions better than a "showing off" lift is gonna be custom fab and at that point may as well just get a K5 chassis and put your Forester body on it, as hillrods have been doing for years.  

Sawzall body off, insert f250 psd frame and running gear. Mix well and enjoy.

Also, with good diffs, skidplates, decent tires, and rally coilovers (~10" travel without having to change much else) you should be able to go wherever you need to... but I understand there's also an appearance factor.

So I am of the opinion that at this point, the only cool lifts are on things that should not be lifted, and the only cool lowerings are on things that should not be lowered and racecars.

Ergo, you should drop your Forester! Much cooler.

But, if you must, and you don't want things like the "important bits" hanging down, clearly you need to follow dropstep's advice and put your Forester body onto a Hummer or Unimog frame! :)

with the subframe lift you also have to realize it doesn't hang down any further then stock, and will actually be higher up with the bigger tires with the new wheel well clearance, so it's not really that bad of a thing. Like someone said a few skidplates and protect anything you're worried about. maybe a combination of a little spring lift and a little subframe lift would be a good balance. or.............

say F-it, dont worry about staying in the fenders at all, and follow the path the guys used when they build the Bajabaru

there are video's of it blasting around offroad and its not just for looks, it has some real suspension travel

In reply to edizzle89 :

I really like the fab work they did on that! But it does look a little ridiculous.

Is your car a 5-speed?  The best gearing solution would be a dual range trans from down under.

Also, I think you're far overthinking the radical suspension mods.  A set of true rally coilovers with appropriate springs and damping plus 28-30" tires would take you about anywhere you could want to go.

I daily'd a 3" lifted outback with 28" tires and pushed its limits offroad many times.  My only complaint was the gearing of the standard gearbox.  A dual range box would have kept my clutch much happier.

Dave M said:

Ergo, you should drop your Forester! Much cooler.

A coworker used to have a Forester XT that was basically an STi underneath. Looked awesome. I have a photo of it towing a bike-engined Lotus replica on a small trailer somewhere.

Stuff hanging down between the wheels (laterally) is less important than stuff hanging down in front or behind the wheels.

¯\_(ツ)_/¯ said:

If you want to go to a double a-arm up front, at that point you're probably making a totally different subframe anyway so basically just go from scratch.  At that point I'd pick a different steering knuckle/upright and, since you're considering different axles anyway, use the outer stub and CV from whatever the upright is off of.  Then have the axle shafts made with the correct length and splines at either end.

At the rear, I think you can get a pretty good amount of travel out of the multilink.  If you really want a ton of travel though, the answer is probably going to be something you fab up, either bigass a-arms to match your front end, or a live axle with a 4-link like what trophy trucks/prerunners use. 

Some inspiration in the form of another vehicle this treatment was applied to:  

See this guy gets me! Even if there's a good chance that none of this ever happens, I think it's still a pretty cool thought experiment to hear so many different viewpoints.

I actually think installing a live axle in the rear wouldn't be that difficult in the grand scheme of things. Doing that in the front would be impossible without a mega stupid monster truck lift.

If you want some more interesting options for super long front travel, WRC cars fit longer McStruts by tilting them and actually going past the axle centerline:  

Or, if you want to go completely the opposite way with it, there's always the extremely wonky but extremely tough Ford TTB, although at this point there's really no benefit to keeping the Subaru transmission at all:  

If this thing doesn't have portal axles at the end of this, it'll be a travesty

I'm frimly in the camp of doing more with less, you wouldn't believe the places I went in a crx with studded snow tires. A minor lift with good dampening and agressive tires will bomb through virtually any forest service road with ease. If you want to get into bouldering or some other sort of really extreme wheeling, you're just starting with the wrong rig. 

That said, portals would be an amazing thing to see, and would certainly give you gearing and clearance.

Don't know much about Foresters but a 2" lift on my Outback gives 12" clearance which is plenty for the gravel roads in the mountains/state parks in MD, WV, and PA.  Lift is strut spacers on the front and a combo of strut spacers and subframe spacers on the rear. I am running the stock size 225/65-17 Yokohama G015 tires and have no clearance problems.  

I approve of a lifted Forester.

Consider adding a center coupling with more lockup if you're going that route, too.

What's the budget?  How do you get any significantly longer strut travel without spending > $2K for custom struts?

Also RE: spacing subframe down.  Moving the subframe down = more room for tire = more ground clearance.  Even though some bits are now dangling below the body more, they are also higher off the ground than they were previously.

I think the practical approach is spacing the subframe down, running ~29" tires, and probably ending up with something more capable than what you're imagining that would be. No amount of subframe lowering is going to equate to less ground clearance than a solid axle anything where the differential housing hangs below the centerline of the tires no matter what. 

Since you want a lift, gearing, not to lower the subframe, and have mentioned making custom uprights... I would say the  one thing that will do all that with minimal modification to the rest of the vehicle is portal boxes mounted on the ends of custom/modified spindles. 

Small portal boxes example.