ditchmyster

iTrader: (7)

Cheers babble, sounds like we're headed in similar directions, but i'm anti coilovers so I think my next step is going to be some stiffer springs and possibly a rear roll bar to lose a little more of the roll.

Have a look at my thread in project section.

https://www.scoobynet.com/projects-4...ily-drive.html

Fat Boy

Positive rake is not a new theory on a understeer prone chassis - it is a very old and well accepted theory that people like John Felstead would confirm. For example - the P1 oem chassis set up by Mike Wood of Prodrive was exactly like this.

Race car set ups are utterly different to road set ups.

The basic theory is that the (marginally) higher rear gives some roll oversteer helping to neutralise the inherent understeering nature of the impreza ( and 4wd/fwd) chassis.

Arnie_1

in regards to the rake debate, be a bit careful in how you determine what rake you use and on what chassis. The front arches on an impreza are cut larger up front so if one goes for the aesthetically pleasing "even arch gap" you are already raking your car. dropping the nose even further to achieve more rake can make things worse. As mentioned above this changes the relation between front and rear roll centers, effectively giving the rear a higher roll center compared to the front, making it feel like it wants to rotate. However, you do then have the lower front roll center issues and potential reduced front travel. As a note Subaru raised the rear roll center on the GD/GG chassis compared to the GC/GF. Also, Prodrive's P1 suspension set up is indeed raked compared to the OEM GC set up, but note that the arch gap is still not "even".

In the end, on a road going car, it will usually be a compromise one way or another. For most of us, our cars arent purpose built racecars and we have to use off the shelf parts to make the improvements we want(or think we want!). And it's a question of fine tuning and optimizing that mixed bag to get the most for our intended purpose. You can have the most expensive ultimativo suspension parts on the car, but if they aren't set up properly, it can still handle like poo.

one other thing to note, as people throw out their suspension tuning recommendations, is that the bane of Impreza handling, understeer, can be, IMO, addressed in two basic ways: either increase grip up front compared to the rear, or reduce grip in the rear compared to the front. Which parts one puts on a car and how they are set up will determine which route one follows. I personally like to maximize grip up front as much as possible then use the rear to fine tune rotation.

Also dont forget that the most important nut to fix is the one behind the wheel. Driver inputs are the single most important part of the handling equation. I've made an E46 M3, with all nannies off, understeer like a greased pig as well as have a completely standard wrx oversteer like some kind of drift king. What one thinks is an understeering chassis, can often times be the fault of ham fisted driving.

in general, one should be mindful of making any sweeping generalizations and suggestions because most things have their pros and cons. Its important to research to find out what you re willing to live with. (wait, i just made a sweeping generalization!).

Dave Y

iTrader: (52)

I have just found out the Bilsteins i have on my car are not height adjustable,so i am stuffed.��

richie001

iTrader: (3)

Er..Dave,I thought you had the same set up as me ?

Dave Y

iTrader: (52)

I thought i had Rich but Ryan said they are ride height non adjustable.

Gambit

iTrader: (6)

you have bilstein coilovers which aint height adjustable?!?!

richie001

iTrader: (3)

Hey Dave have you got b12 or b14 mate ?

Dave Y

iTrader: (52)

B14 Rich.

Gambit

iTrader: (6)

Silver casings yeah? B14 are height adjustable. Can you get a pic of them?

richie001

iTrader: (3)

Dave if they are B14 mate then they are ride height adjustable.

http://www.bilstein.de/en-uk/product.../bilstein-b14/

I know that because I had Indigo-GT raise the ride hieght after Litchfield set it far to low

Dave Y

iTrader: (52)

Cheers Rich i have checked with Litchfields what coilovers they fitted and they are adjustable.Ryan is having another go.

Dave Y

iTrader: (52)

Drove the car back from Ryan's at Leominster across country to Tewkesbury,what an improvement.The car is into Powerstation tomorrow for a geo setup.
Thanks to everyone who gave advice,thanks to Ryan for doing a top job fitting the parts.
Now back to saving hard for the engine build.

jura11

iTrader: (7)

Seen yours car there Dave

There are awesome roads around the Leominster,always we are very happy drive there

Jura

Dave Y

iTrader: (52)

Curtis at Powerstation did a full geo setup today.He said the backend had been set up totally wrong.I wont dwell on that but will say the car has been transformed.He did say I would benefit from fitting an ALK but then I would need another geo setup.
At £95 a go I think I will manage without.

bonesetter

iTrader: (9)

TBF Dave, £95 for a geo setting is quite frankly a rip off. I don't care who they are, or what experience they have

If you have a settings spec, the likes of which many of us have posted on here many many times over, which are tried & tested, and you take that to a shop who has a reasonable Subaru familiar technician, they will be able to dial those settings in, no problem

I use my local Chemix who for a full set up, taking an hour or so will charge £60 all in.

Usually for tweaks they charge £10- £30, so if you fit your ALK it's only the front toe which should need a small tweak

Powerstation have big overheads though - look at the size of the place

Dave Y

iTrader: (52)

Curtis said the back would have to have a slight tweak as well.No worries because I wont be fitting the alk anyway.
I am going back to serious saving for the engine 2.1 build.

fawor

iTrader: (3)

you referred to alignment not geo set up.
Full geo set up could take 5h with preload,camber,coilovers height etc
who charge 6 per hour then?

bonesetter

iTrader: (9)

Fair comment and TBF I've jumped the gun as I don't know what was involved for £95

However, I've had an alignment done there and it cost the same, and that was 5 years ago

Dave Y

iTrader: (52)

I think I have caused the confusion it was a 4 wheel alignment that I had.
Apologies !!

bonesetter

iTrader: (9)

For £95 I guessed that was the case

Dave Y

iTrader: (52)

Now the brakes have bedded in i have given it a bit more right foot,the suspension works a treat now.