Subaru Forester Owners Forum banner
1 - 20 of 34 Posts

·
Registered
05 XT2.5
Joined
·
1,995 Posts
Discussion Starter · #1 ·
I'm running 22mm WL sways all round with the rear on the hardest setting. I also run coilovers, 18's, decent alignment, braces, ALK, yadder yadder. Got a nice ride on pretty crappy roads but when I get enthusiastic I'll get understeer leading to front wheelspin. I get 380lbs/ft. I've been thinking I'd like a front LSD but it's a lot of bother which started me on sways. I considered a 24 adjustable but I could go 27 and have the 'ultimate' front sway keeping the 22 on the rear.

I know some on here have the 27 so my questions are will it tame the understeer and are there any drawbacks or should I just go 24. I don't really want to do the job twice. I've already had 2 front sways - I broke the 25mm Cobb hollow which led to the 22mm WL. It's a street car - no track stuff - but over here in the little old UK we have lots of those funny corner thingies...
 

·
Registered
SG9 Forester XT Stick Shift
Joined
·
1,667 Posts
I have 27 mm FSB and actually pretty surprised at how good the ride is. Mind you I am using STI RSB, Swift and Koni so the ride would not be the same as your setup.

I actually bought it because the seller advertised it as 22mm.

I really like how it improve turn in and front grip. I like it a lot more than when I am running 24MM FSB & RSB combination.

I am running stock endlink front and rear and they haven't failed me yet even with a few auto cross event.
 

·
Premium Member
2004 Forester XT 5 speed
Joined
·
1,042 Posts
Increasing the bar stiffness even more on the front is only going to reduce grip at that end. Take it off completely & go for a spin, see what happens. Lots of body roll, and lots of oversteer.
 

·
Premium Member
2017 VW Golf SportWagen 5MT
Joined
·
10,784 Posts
^^I'm going to guess you never tried running larger front bar on a Subaru with upgraded suspension.

Go for it, it would be a better match for your rear bar than what you have now and should tighten up the front nicely. I ran a 24mm front with 22mm rear and it worked well.

IMO a larger front bar on a Subaru is the best upgrade, I have no idea why everyone isn't doing it after upgrading the rear. Funny thing is, everyone who tries it enjoys it, yet people are still sceptical and continue the "it will understeer more" mantra.

Stan
 

·
Registered
05 XT2.5
Joined
·
1,995 Posts
Discussion Starter · #5 ·
Well that 'more rear bar reduces understeer' works with some some cars but it seems not Subarus. I take it the part # I need is BSF36XXZ?
 

·
Premium Member
2017 VW Golf SportWagen 5MT
Joined
·
10,784 Posts
It is a general rule, yeah. But the larger bar preserves negative camber when cornering so grip and it's limits increase.

Do a simple test: disconnect the front endlinks and go for a drive through some turns. Using the "moar front bar = understeer" theory, should the car understeer less?

27mm may be a bit too much, 24mm on stiff setting will be close enough to 27mm on soft setting. But either should be an improvement.

Stan
 

·
Premium Member
2004 Forester XT 5 speed
Joined
·
1,042 Posts
^^I'm going to guess you never tried running larger front bar on a Subaru with upgraded suspension.
Nope. :) But in every other car I've owned, I don't like to use too much sway bar - on the front or back. Much prefer to fix roll stiffness with springs & shocks as much as is comfortable, and then fine tune with a rear bar for cornering attitude. Keeping as much independence as possible for bumpy roads.

It is a general rule, yeah. But the larger bar preserves negative camber when cornering so grip and it's limits increase.
If he's already on coilovers, spring stiffness & reduced suspension travel should be enough to prevent negative camber loss. And if not, I'd much rather ran an extra degree or two of negative static camber than use more sway bar.
 

·
Premium Member
2017 VW Golf SportWagen 5MT
Joined
·
10,784 Posts
Here we go, picking apart guy's suspension setup without ever seeing his car or roads he drives lol.

He is happy with the ride, stiffer springs may make it worse and less compliant on rough roads. He wants more grip in front, more bar should help with that. His rear bar is same size as front, not too well balanced there. More negative camber and caster in front is great but camber plates are more expensive than a bar. I ran -1 in front with 24mm bar and it was great in the twisties, but my car only put down 270wtq. If OP's torque figure is at the wheels and comparible to Mustang reading of my car, that's A LOT of power.

For an easy one step at a time change, it's a no-brainer and is easily reversed if results aren't positive.

Stan
 

·
Registered
2008 GRB 20th anniversary 6 MT
Joined
·
6,588 Posts
The stiffer end will loose grip first at the limit.
Try using twice stiffer rear springs at the rear compared with the front and the car will become an oversteer animal.

on good dry tarmac a stiffer front bar will help but on wet/slippery surfaces it will need attention and you will not have progressive understeer.
 

·
Premium Member
2017 VW Golf SportWagen 5MT
Joined
·
10,784 Posts
"At the limit" is key here, that limit will be higher though. How often are you guys hammering your cars at their limit on the street in the rain?

Stan
 

·
Registered
2008 GRB 20th anniversary 6 MT
Joined
·
6,588 Posts
Yes, the limit will be higher but on greasy twisty roads it can be reached and the last thing I personally want is a non-progressive car.

I guess US roads are different though.
 

·
Registered
SG9 Forester XT Stick Shift
Joined
·
1,667 Posts
Got to remember that Forester weight distribution are 60-40. And the engine are hanging in front of the front wheels. Unless you are driving in very tight autocross track stiffer rear bar would actually not beneficial.
 

·
Registered
2008 GRB 20th anniversary 6 MT
Joined
·
6,588 Posts
Hey Jon, I recognised you, my reply was in response to the comments from our US friends :)

Ditto, the weight distribution in the Forester is 60/40 (57/43 to be precise in the FSTi) but don't forget that Prodrive (in the RB320) and STi (in the RA-R and S204) setup the cars with 20/21mm front and 22mm rear bars.

There must be a reason and that is to reduce understeer/make the rear more tail happy and the car more balanced.

My car with 21mm front (OEM) and 22mm rear bars (RB320) is balanced very well for my liking.

In fact with the stiffer front springs of the B14 coilovers that I am using now, I would also like to reduce understeer a bit (I haven't managed to make the rear loose grip even on track and with the Michelin PSS) but reading the comments of others and the trouble they had with the fitment of front ARBs I am going to leave it as it is and just play with tyre pressures.

Jon, do you get understeer when powering out of bends or when using constant throttle and just exceeding the limits of grip?

If it's the first only a LSD will help IMHO.
 

·
Registered
2007 FSTI and X 6 MT
Joined
·
22,252 Posts
Our Forester is an oversteer animal with the sways above and the center diff set at 31/59. Even before the trans swap back when it was a VDC 4EAT it would oversteer pretty easily.

A lot of factors play into the equation like road conditions, suspension set up, tires and pressure, driver input and throttle input.
 

·
Registered
2008 GRB 20th anniversary 6 MT
Joined
·
6,588 Posts
Tuned200, you have done great work in your project, hats off to you but we don't have a 6-speed DCCD unfortunately.

Yes, it depends on the conditions, I can break traction on 3rd gear and 45 degree bends when powering out at 70-80mph when provoked with the steering, great fun!

That was in summer with the Vredestein Sessantas, I haven't managed to break traction with the PSS yet!
 

·
Premium Member
2004 Forester XT 5 speed
Joined
·
1,042 Posts
For whatever it's worth, my SG's weight distribution w/ a driver isn't 60/40. More like 56/44.

Picture taken with about 20 pounds of gear in the back, though. And this is before my new battery, which cut 14 pounds off the front. :shrug:

yes the limit will be higher but on greasy twisty roads it van be reached and the last thing i personally want is a non progressive car.

i guess US roads are different though.
Quite a bit - I've only driven a couple thousand miles around the UK, and the US is so big you see vastly different road quality depending on the area (and how much money that particular town spends).

But overall, US road quality is much worse, especially anywhere in the northeast. Anywhere with a winter you've got large cracks, potholes, broken pavement, and frost heaves. Anywhere without a winter you've got very old roads, where the only maintenance done has been half-assed.

My experience in the UK (all northern & scotland) was that asphalt quality was overall much better, I don't remember hitting or dodging a single pothole. But there's a lot more undulation in the surface & unexpected camber changes. That, and the asphalt is MUCH rougher (explaining why you guys go through tires so much more quickly). The rougher asphalt is grippier overall especially on damp roads, but when you do run out of traction, it happens FAST. Found that out a few times on some of the one-track lanes in my little Peugeot rental. :eek:
More negative camber and caster in front is great but camber plates are more expensive than a bar.
Ah, he said he had coilovers - so I figured camber plates in the front already. And enough rear camber adjustment should only cost about $30 for some bolts.
 

·
Registered
SG9 Forester XT Stick Shift
Joined
·
1,667 Posts
Daemione, thanks for that weight distribution info.

I am not saying that 27mm FSB is the best. If I haven't try this myself I would say this is too much too. I got mine accidentally due to seller's mistakenly represent it as 22mm. I am just surprised at how good it handles and still giving very comfortable ride. Comparing the added stiffness from OEM 20mm FSB and 17mm hollow RSB (which are closer to 13mm solid) my current 27mm FSB and 20mm STI RSB somewhat still maintain the same front and rear stiffness ratio but it have a lot higher grip limit.

The only true perception that thicker FSB would cause more underster is on snow and ice. Soft OEM suspension are best for low traction situation anyway. I could still rotate my car very well on snow but I have to induce weight transfer a lot more than when the car still on stock suspension.
 

·
Registered
05 XT2.5
Joined
·
1,995 Posts
Discussion Starter · #20 ·
Lots of good info here thanks. Fivos no probs on the exit - understeering on a closed or part throttle on the entrance. I think I could get the gas open earlier and balance the car better if I could avoid the understeer. I've got loads of adjustment left on the shocks but then the ride gets too harsh.
 
1 - 20 of 34 Posts
Top