boma23

Hi All,

A relative newbie to Scoobies here, having recently took possession of a tidy 2006 WRX Wagon with the PPP 266 pack. It's got impressive grip levels and the suspension feels fresh overall, although the OZ ProDrive 18s feel crashy over small stuff. I'm already getting the suspension fettling bug with what can be improved though.

To help me make a more informed choice fr my intended use, does anyone have definitive info on the factory PPP setup for the Wagon? In particular, I'm looking for:

1. hub centre to arch heights when new
2. what are the factory PPP spring rates and curve type, F+R? (or is this the same as the STI PPP?)
3. did it have -ve rake from the factory, or do I have a little bit of sag?

There's tons of god info in the sticky at the top, but most seems centred around the widetrack STI variants, so not sure how applicable, and not much coming up in search.

Don Clark

Is it just a standard wagon with the Prodrive Performance Package (PPP) fitted with the recommended wheel upgrade to 18" ? or is it a GB270 Sports wagon with all the additional upgrades to suspension etc.but didn't appear until July 2007




2006 WRX PPP upgrade (which is only a power upgrade)
2006 Prodrive Performance Package pdf

2006 suspension spec




2006 ride height

boma23

thank you!! perfect - that's a load of stuff to be getting on with and check against this weekend..

It's not a GB270, but a Standard 2006 Wagon fitted with the PPP . It has all the paperwork with it including the ProDrive certs etc. and goes like I would expect it too.

So that means standard suspension then! I had mistakenly thought after reading somewhere the PPP included Eibach springs as well, obviously not (maybe that's from the Prodrive aftermarket Eibachs offered elswhere)

I'm not looking to drop the car at all due to local roads, but reduce/remove understeer is a big yes, which looks like some combination of lifting the rear slightly, and/or stiffening / lengthening the rear springs and ARB. I'm not looking to go mad, and this is a road only car only that lives outside of the UK now, but I do push hard and and like an aggressive setup having ran very track biased cars previously. The car already has a healthy amount of mechanical grip so adjusting its' balance is way more important to me than outright increase in grip and stiffening / lowering.

This is a pic form the last owner (who's probably lurking here somewhere, I should have asked )



The info supplied is perfect - thanks again. I'm going to compare what you've supplied below against the vehicle, and go away and read/research a bit more, before making some decisions.
Cheers

Dom

TECHNOPUG

iTrader: (1)

You could try simply adding more camber and castor to the front and a proper geo steup.

They benefit from a slight drop at the front but then you will need new springs all round.

boma23

Thanks for the suggestion. Sadly I'm limited in what I can do here - it's a small island, no main workshop facilities, and any alignments I've done on my vehicles last few years have been by myself with string/straight angle metal, and a tape measure - there's no rig here to do even a basic garage laser alignment, let alone proper 4 wheel job. Balancing tyres involves lining up the red dot with the valve and hoping for the best (thankfully there's not many high speed sections on the island!). Hence I'm reluctant to make major changes or start unbolting a lot of things, as it had a recent 4 wheel alignment with previous owner (although not sure if to factory or tweaked).

However, if adding a spot of castor is as easy as the whiteline ALK kit or even some Forester LCA bush mounts, without messing with loosening other adjustments points, then that sounds more than do-able

Just been out with the tape measure and she's at approx 375mm F, and 355mm R , so would indicate either 10 and 20mm sag from new, or she's had springs at some point, so a little investigation needed there also, and a dig through the old paperwork.

TECHNOPUG

iTrader: (1)

I'd fit these top mounts for max castor/camber, with minimum effect on wallet and ride.

https://ukwhitelineperformance.com/c...35-strut-mount

I have fitted them to my 05 Wagon and they are very accurately manufactured, meaning that both sides should see a matched castor/camber increase, so you should be able to keep your current alignment settings. Just be sure to mark up the camber adjustment bolt on the shocks so you can reset it back after fitting. These fitted increase turn-in, front end grip & steering weight. They aren't going to change the F/R balance per se but you may find that sharper turn-in and reduced understeer is all you need.

You could also address any slop in the suspension by replacing the front & rear anti roll bar bushes and also the steering rack bushes. These are cheap and easy to do.

It's important to be aware that increasing the rear ARB size, also increases the rear spring rate, which can then have consequences for how the car rides and may require further work/parts etc. So I would try all the cheap and easy mods/work first before opening pandora's box and start changing spring rates. For example, simply playing about with the tyre pressures (higher at the rear) can have positive effects on handling.

John 37

Changing ARB has no effect on spring rate, only on roll resistance. Spring rate us the resistance to vertical deflection under load such as when a load is put in the boot.
+1 for tyre pressures. This is the cheapest way of tweeking handling especially on a fairly stiff car like an Impreza.

2pot

iTrader: (3)

I'm sure @TECHNOPUG meant wheel rate.
Bar would effect the bounce rate, if the clamping force of the bar bushes was excessive
Or, what about a single wheel deflection?