I've got an 06 STi Spec D and have the expected R/N/S strut knock, so need to change the strut. The car is out of warranty, and has covered 98,000 miles, and as I'm on the original R/O/S strut as well as the original fronts and springs, now seems a good time to change the whole lot.

I'm looking at either the AST setup from Powerstation, or the RB320 kit offered by Prodrive. The one thing I am after is to improve the ride quality of the OE suspension setup - something I guess either kit will be more than capable of.

Just wondering what the opinions of those who have gone either from the OE STi suspension setup to the RB320 kit, either by modifying the car or obviously changing from an 06/07 STi to RB320, and how the ride compares.

The AST setup seems to get good reviews and comments, but does anyone have experience of how it compares to the RB setup ?

I've searched already, so have a feeling for the comments for each type, but wondering how they compare.

Cheers

Gareth

 

When you say 'improve the ride quality' what are you exactly after? I can see the AST's being quite firm over OEM.

 

I guess what I'm after is to make the ride more composed and compliant - remove the bounce that seems to exist on motorways and A roads. Not the most technically accurate descriptions I appreciate, but as I do a lot of mileage its a case of making it easier to live with on the long runs.

I don't mind a firm suspension, just not as "crashy" as the current STi setup. Having done nearly 100k in the STi I'm looking to improve it. Its only fast road use, on all road types, not track, which is why I think the AST may be overkill with its adjustable settings - if the RB320 setup is designed for road use, it may be a better option.

According to the Prodrive website, "The suspension modifications, whilst being stiffer than the standard road car, provide a more comfortable and controlled ride. Driving on country lanes becomes more rewarding and the ride quality is improved significantly on all types of road. The steering feel has been enhanced by the suspension changes making the car easier, and safer, to drive quickly. The level of understeer is reduced with the new set-up and the car is more responsive to throttle changes making it more fun to drive."

I guess thats what I'm looking for, but does it actually deliver this ? As well as this there is the improved looks with the lowered springs, but that stands for the AST setup as well.

 

I went for this option (on a GB270 wagon though) and this is such an improvement over the standard WRX shocks and prodrive springs that the GB270's have as standard. Standard shocks, prodirve springs, 20mm front ARB and uprated 19mm rear ARB (measured with a micrometer whilst off the car before people start disagreeing with sizes).

Had the stage 3 Type 25 kit plus alloy drop links all round.

Handling and feel are vastly improved in almost all situations.

run the AST's on 3 front and 2 rear on long journeys to soften things up and find it a better ride with this than the prodrive springs - still firmer but less 'bouncy' and 'dippy' than the normal suspension.

run the AST's at 6 front and 4 rear day to day and 8 front and 6 rear for a bit of fun.

only time the suspension is worse than standard is on bad unmade roads (which act like rumble strips but with potholes) - the AST's do not like this and it sets up an increasing rumble/shake in the car. 'A Doppler effect' maybe?

Best mod/best improvement I've ever done on a car.

What's the price comparison between the two though?

 

Thanks for the comments.

The price is similar, but the RB320 kit is just springs and dampers, whereas the AST setup includes anti-lift, as well as front and rear anti-roll bars and includes fitting and the four wheel alignment - I'd have to factor in the fitting costs and alignment on the RB kit. So in terms of value for money I'd say the AST kit is a bargin compared to the RB kit.

Interesting comments about the setups that you use for various situations, that is obviously a real bonus.

Cheers.

 

Do let us know how you get on either way you go Gareth - I've recently acquired a Spec D and agree that the suspension is harsh for daily driving.

 

Hi, I'm having the RB320 kit fitted on Tuesday - new dampers, springs and the Prodrive adjustable rear ARB. I decided that for my driving this would be the best option and it means I can get it sorted by my dealer who I have a great relationship with. The AST option seemed a bit too much hassel for me.

I'll let you know how I get on when its fitted, but its going to be a bit of a strange comparison due to the fact that I'll be going to the new RB320 kit from tired 100,000 mile old STi supension - with one strut thats failed.

I'm expecting the ride to be firmer but if the new suspension controls the crashing and poor ride quality at speed, then I'll be happy.

 

G'day Gareth - how did you get on? :-)

I drove my wife to Dublin airport earlier this week (110 miles each way) and she complained about the bouncy ride the whole way - and to be honest, I can't blame her! It was shocking...