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Old 01 July 2015 | 10:30 AM
  #151  
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Originally Posted by InTurbo
Goes to show you don't need a rock hard ride to have a good handling car.


Unfortunately not many people realise this.
Old 01 July 2015 | 10:49 PM
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Originally Posted by InTurbo
Very happy, It's been a good learning curve or be it a expensive learning curve over the past year.

I now have a car that's fun, confidence inspiring and a joy to drive over UK roads, Especially A B roads its planted and works with the bumps and undulations.
I love the damping on the Bilsteins there firm but somehow weirdly comfortable.
I still see unavoidable pot holes coming and I cringe before I run over them.
Then it's like ( oh thats not bad )
Where as before it would crash over them.

Very impressed with the way the car rides now. Goes to show you don't need a rock hard ride to have a good handling car.
This has been a great read, thanks for seeing it through to the end.

So did you end up with the Bilstein/ Pca spring combo and larger rear roll bar?
Old 02 July 2015 | 12:35 PM
  #153  
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Originally Posted by Berks-Jack
This has been a great read, thanks for seeing it through to the end.

So did you end up with the Bilstein/ Pca spring combo and larger rear roll bar?

Yeah so to recap the Full set up is

Prodrive Bilstein dampers from Rb320 supplied by Subaru

Prodrive eibach springs supplied by PCA dynamics

Prodrive rear adjustable 21/22mm roll bar supplied by PCA dynamics

Oem 20mm front Sti roll bar

Whiteline anti lift kit

Geometry is

Front camber 1.20 (ideally 1.30)
Front toe 0.03 total 0.06

Rear camber 0.55
Rear toe 0.03 total 0.06

Roll bar set to 21mm

Heigh 355 front 365 rear centre of wheel to arch
Old 05 August 2015 | 03:42 PM
  #154  
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I've just bought a blobeye WRX and the handling feels a bit wallowy, so I was told to get an STI rear ARB... The car is completely standard; should I scrap that idea and save up for a set of coilovers instead then? I have a leaking rear shock which needs replacing anyway.
Old 05 August 2015 | 09:17 PM
  #155  
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Originally Posted by Ash Knight
I've just bought a blobeye WRX and the handling feels a bit wallowy, so I was told to get an STI rear ARB... The car is completely standard; should I scrap that idea and save up for a set of coilovers instead then? I have a leaking rear shock which needs replacing anyway.
The oem sti 20mm rear bar are no way near as stiff as a 22 or 24mm bar.

I now have a 21mm that's a nice compromise.
Old 05 August 2015 | 10:51 PM
  #156  
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Originally Posted by InTurbo
The oem sti 20mm rear bar are no way near as stiff as a 22 or 24mm bar.

I now have a 21mm that's a nice compromise.
Ah ok, I'm just looking for a cheap, quick way to stiffen up the suspension a bit while I save for coilovers :P
Old 06 August 2015 | 11:52 AM
  #157  
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Originally Posted by Ash Knight
Ah ok, I'm just looking for a cheap, quick way to stiffen up the suspension a bit while I save for coilovers :P
Just make sure you get the right suspension for you intended use.
Otherwise your wish you never bothered fitting them.
Old 06 August 2015 | 03:25 PM
  #158  
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IMO you should sort your shocks out before investing in new ARBs.

Personally I prefer the fixed strut and spring route for a road car although there have been been good reviews posted lately of HSD and Meister-R coilovers.
Old 06 August 2015 | 03:40 PM
  #159  
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Originally Posted by plenty
IMO you should sort your shocks out before investing in new ARBs.

Personally I prefer the fixed strut and spring route for a road car although there have been been good reviews posted lately of HSD and Meister-R coilovers.
Yeah that's what I thought interesting, would something like the Pedders kit be something good to go for? Or STI setup? New to the Scooby scene too much to buy and not enough money
Old 06 August 2015 | 06:40 PM
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On page 5 of this thread I posted up my own suspension journey based on my personal requirements.

There was a review of the Pedders gear posted up on the Suspension forum this week.

IMO you won't go far wrong with the PCA Dynamics blue springs with OEM shocks - which also has the advantage of being cheaper than most other solutions. You could always add ARBs later if you still want to stiffen things up further.
Old 08 November 2015 | 01:31 PM
  #161  
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Originally Posted by InTurbo
Yeah so to recap the Full set up is

Prodrive Bilstein dampers from Rb320 supplied by Subaru

Prodrive eibach springs supplied by PCA dynamics

Prodrive rear adjustable 21/22mm roll bar supplied by PCA dynamics

Oem 20mm front Sti roll bar

Whiteline anti lift kit

Geometry is

Front camber 1.20 (ideally 1.30)
Front toe 0.03 total 0.06

Rear camber 0.55
Rear toe 0.03 total 0.06

Roll bar set to 21mm

Heigh 355 front 365 rear centre of wheel to arch
It's interesting to see your ride heights are now higher at the rear than the front,generally they almost always are the other way round on an Impreza.

This does seem to make sense though as I have a widetrack sti with front ride height of 370mm and rear 350mm and the front lower arms do still have a decent amount of droop (ie decent roll centre) but the rear lower arms are indeed level no droop at all.

So the way I see it I have 2 options either raise rear ride height, or fitt taller ball joints to rear lower arms?(roll centre kit).

Last edited by Nismoboy; 08 November 2015 at 01:36 PM. Reason: Spelling mistake
Old 11 November 2015 | 11:48 AM
  #162  
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Originally Posted by Nismoboy
It's interesting to see your ride heights are now higher at the rear than the front,generally they almost always are the other way round on an Impreza.

This does seem to make sense though as I have a widetrack sti with front ride height of 370mm and rear 350mm and the front lower arms do still have a decent amount of droop (ie decent roll centre) but the rear lower arms are indeed level no droop at all.

So the way I see it I have 2 options either raise rear ride height, or fitt taller ball joints to rear lower arms?(roll centre kit).
I've not come across any roll centre correction for the rear of the car.
Don't know if anyone else has??

Think your only option would be to raise the rear height slightly, when my car was on coilovers a raise of 10mm made quite a difference to the angle of the rear control arms.

What suspension set up does your car have?
Old 11 November 2015 | 12:39 PM
  #163  
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Hi inturbo, this my sound like a silly question but what size bushes have you used with your prodrive arb? just got my own rear rb320 prodrive arb off eBay.

Tom
Old 11 November 2015 | 01:29 PM
  #164  
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Originally Posted by Sti_tom
Hi inturbo, this my sound like a silly question but what size bushes have you used with your prodrive arb? just got my own rear rb320 prodrive arb off eBay.

Tom
Sourced mine through Subaru, on the receipt is says 20464FE050, x2

Kinda confused me as the bush has 19mm on it. But I'm assured it the correct part and it does fit.

Maybe they used a slightly smaller internal diameter bush so it's tighter on the bar making it have less flex in the bush.

Last edited by InTurbo; 11 November 2015 at 07:36 PM.
Old 14 November 2015 | 04:23 PM
  #165  
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Originally Posted by InTurbo
I've not come across any roll centre correction for the rear of the car.
Don't know if anyone else has??

Think your only option would be to raise the rear height slightly, when my car was on coilovers a raise of 10mm made quite a difference to the angle of the rear control arms.

What suspension set up does your car have?
I'm using bc coilovers,Thanks for the info I'll try raising it 10mm at the rear as you suggest and see how I get on.
Old 21 November 2015 | 04:01 PM
  #166  
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Hi Just another vote for the PCA dynamics Rear ARB setup. I spoke to Peter and asked him what a good fast road setup would be. He replied that the best set up was similar to the RB 320. He was of the opinion that the STI strut was a good unit and a spring and ARB change was all that was needed for a good compliant but controlled ride. I purchased an adjustable PCA Rear ARB, designed to work with standard STI bushes. After a couple of broken bolts I handed it to Richard Henry of Bradford who sorted it very reasonably. So what was it like? First impressions driving it round town accelerating off roundabouts and urban motorways were that roll was much much smoother and more progressive with none of the lurching and unsettled feeling which had disappointed me when I got the car. Later on trying it on fast twisty roads and roundabouts confirmed the more planted ride and a much more neutral balance with slight rear bias rather than the push on understeer previously felt (perhaps need to experiment with DCCD more). So generally it has been quite a revelation how much effect changing the roll bar has had. I hope further improvements will come with changing the springs as suggested for the Prodrive/RB320 style ones developed for the STI by PCA dynamics. Although quite expensive they are still cheaper than coilovers and should produce a ride both comfortable (I live in Leeds) and controlled. I will let you know.
Old 28 November 2015 | 04:10 PM
  #167  
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I'll be interested to hear your thoughts on the springs with standard dampers mate, I think I'm gonna go down that route instead of coil overs, I've already got the RB320 adjustable bar, got to fit it yet so might just wait until I get the PCA springs and get it all done at once, how much were you quoted for the springs if you don't mind me asking, PM me if you'd rather.
Old 15 December 2015 | 03:41 PM
  #168  
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Sorry to jump in at the last minute, but fascinating read.

I've got a 2003 Blob Sti, Spec C shocks with red Prodrive springs. Fast road use, rough roads but occasional motorway.

I'd like a comfortable but planted feel, had considers Whitleine front and rear arb, drop links etc. but what would you recommend?
Old 19 March 2016 | 10:46 PM
  #169  
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Hi everyone.
Just a update on how the cars been handling over the past few months.

Im still massively impressed with the way this Blistein / eibach combo just works everywhere.
No mucking around with damper adjustments because the roads to harsh or the cars rolling to much.
Just constant predictability and confidence in how the car behaves.

Changed a few other things since I last posted, first being that the car still had the roll centre correction kit fitted from when it was on coilovers,
So they were swapped out and replaced with oem items.

This has lowered the front roll centre to where is should be with this particular Spring damper combo.

Hard to tell if there's much improvement in doing this but it should help the car transfer weight across the front axel more to help turn in.

Secondly I have been experimenting with toe. A friend of mine has a track ace alignment kit.

Only tried it on the front so far as it's quite time consuming setting it up adjusting testing and repeating.

Turn's out I prefer 0.00 up front.

I tried these toe in settings
0.025 total 0.05
0.05 total 0.10
0.10 total 0.20

And one toe out setting of
-0.05 total -0.10

Toe out was defiantly tugging at the wheel over bumps and under hard breaking,
But did have a crisper turn into roundabouts.

Toe in was interesting,
At the larger end of the scale 0.10 per side I was getting scrub on the front wheels while doing tight turns.
And the steering felt numb and unresponsive, hard breaking kind of the same as toe out with the front end moving around just before coming to a halt, Not what I expected.

Between the 0.025 and 0.05 I would say the lower of the two was better not that there is much difference but
Steering felt a little better and still felt stable and hard braking was straight.

But 0.00 I found best for me. Steering is responsive, no problems with straight line stability and hard braking is straight with no tugging at the wheel.

Hopefully when time allows I might get to play around with the rear and see how that behaves.

Finally the biggest improvement I've had was in the last week.
I fitted the Whiteline Kca335 camber castor correction top mounts and the results are impressive.

I fitted them in the highest camber/ castor position. Thinking I could use the stock camber bolt's to reduce as necessary,
After having the car aligned my caster is now +4.50 and the lowest front camber I could get was -1.50.

At first I thought the camber was maybe a bit to high for road use, and I was going to rotate the top mounts to the lower camber position and then return for another alignment.

But after going out for a good drive I have totally changed my mind,
Then front end is epic, This is one of the best pound of pound mods I have made to my car.

Straight lines stability has massively increased, steering feel is awesome and the way the car darts into a corner then grips and grips is fantastic!

Only slight down point would be that the duro rubber used in the mounts is fairly stiff stuff, There is no increase is road noise but there is a added harshness over pot holes.

The front camber setting is also a worry yes it feels amazing with the extra castor but I may encounter some excessive tyre wear.
I've measured the tread depth on the inside of the tyre and I will keep a close eye on it. If it starts becoming a problem I'll take half a degree or so out.

So I would defiantly recommend fitting this part. One more thing to note is this the +4.50 castor was also in combination with the anti lift kit I already had fitted.

So just to recap the cars now running.

Front castor +4.50
Front camber -1.50
Front toe 0.00

Rear camber 1.10
Rear toe 0.03

Whiteline kca335 front strut mount
Whiteline kca359 anti lift
Rb320 rear roll bar
Rb320 dampers and springs

Eagle eye people might notice the rear camber has increased ever so slightly.
I think this is due the the springs settling slightly. If I can find my tape measure I'll re check the ride heights to confirm this.

Daz.
Old 19 March 2016 | 11:24 PM
  #170  
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Great write-up Daz, thanks for sharing. Interesting how caster has such a positive effect on steering feel, any idea how much caster spec C's run? Why would increased caster increase tyre wear though?
Old 19 March 2016 | 11:28 PM
  #171  
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It's the increase in the camber that might cause a problem with tyre wear. Lowest equal setting I could get was -1.50.

Not sure what the spec C runs, in fact I wonder what the oem spec C setting are?
Old 19 March 2016 | 11:50 PM
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Originally Posted by InTurbo
It's the increase in the camber that might cause a problem with tyre wear. Lowest equal setting I could get was -1.50.

Not sure what the spec C runs, in fact I wonder what the oem spec C setting are?
Sorry my bad, re-read it, thought you said it was the caster that was worrying you.

After a quick google looks like spec C's run +5deg caster, think that is achieved with high caster wishbones which increases the wheelbase, I take it with the top mounts changing the caster angle wheel base stays the same?
Old 20 March 2016 | 12:08 AM
  #173  
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Yeah I guess the wheelbase does remain the same with the topmounts, but the anti lift should add slightly to the wheelbase.
Old 20 March 2016 | 12:28 AM
  #174  
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Originally Posted by InTurbo
It's the increase in the camber that might cause a problem with tyre wear. Lowest equal setting I could get was -1.50.
According to Whiteline kca335 is group n rubber.

You could use these, if necessary, for less (or more) front camber - the cam is bigger than oem camber bolts.

Camber Bolt Kit 16mm
Old 20 March 2016 | 01:36 AM
  #175  
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Thanks 2pot, Do they have more adjustment than the eibach ones?
I will get a set if it starts eating through tyres, but for now I'm loving how it feels.
Old 20 March 2016 | 09:21 AM
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Originally Posted by InTurbo
Thanks 2pot, Do they have more adjustment than the eibach ones?
I will get a set if it starts eating through tyres, but for now I'm loving how it feels.









Last edited by 2pot; 20 March 2016 at 09:33 AM.
Old 20 March 2016 | 09:49 AM
  #177  
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Can these be used in the lower front strut mounting hole to reduce camber? I was told as my car has a slotted top hole you can only use the oem bolt in the upper position to provent slippage.
Old 20 March 2016 | 04:35 PM
  #178  
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If it proves necessary, I'd just rotate the top mount to the max caster/min camber position.
Or, drive faster.
Old 21 March 2016 | 02:41 PM
  #179  
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Good feedback and good to hear you're enjoying your car's handling

I don't think you need to worry about the camber. one and a half deg up front is fine for a hooner. If you were doing long motorway miles, different story, but I don't think you'll see much if any uneven wear.

You will preserve static camber as you have more castor, so that's something to bear in mind

Interesting you prefer neutral toe. I have always ran a bit of toe-in all round (sometimes referred to as 'Prodrive settings').

Have you seen this Peter Cambridge article?




What is the rotational balance like now?
Old 21 March 2016 | 08:17 PM
  #180  
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My alignment was in degrees and minutes so it's more nearer 2 degrees,
I measured my inner tyre depth and it currently at 6mm, I'm going to keep a eye on it so if there's any extreme tyre wear I'll reduce it.

Yeah I've read the article, some good info there.
I personally think my car felt more responsive with the front toe set parallel, This was before I had the increase in castor and camber so might be worth playing around with it again some time, Although I'm reluctant at the moment as it's the best it's been.

Rotational balance, Well considering the front end now feels super responsive and glued when you lean on it, It does feel slightly more active but in no way like it's going to step out unwanted. Rear bar is on the softer setting at the moment tho.


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