I have been looking into fixed-perch options for my 2004 STi and have been in conversation with the extremely helpful Peter Cambridge of PCA Dynamics. I thought I would share findings on this thread in case it is of use to others.

There were two versions of the Prodrive Red springs manufactured for newage cars:

- The early version, part number S03/D5/001 - these are a little softer and were used on the WR1.
- The later version, part number S05/D5/001 are firmer and were originally offered for widetrack cars although will fit non-widetrack as well.

Both Prodrive Red versions are interchangeable in terms of fitting.

RB320 springs, part numbers LE07/D5/001 and LE07/D5/002, are black in colour and are comparable in rate to the later Prodrive Red (S05) springs.

RB320 front springs are interchangeable with Prodrive Reds, but the RB320 will sit lower by 8mm.

RB320 rear springs will only fit an RB320 Bilstein strut which is a slightly bigger perch diameter (comparable to a classic perch).

Peter is now working with Eibach to produce a fresh batch of springs to be compatible with non-RB320 struts, which will be a combination of RB320-style lower fronts (with the exact amount of drop being finalised by Peter and Eibach), with S05 rears. Peter also has brand-new RB320 rear anti-roll bars available (21mm adjustable).

Hope this is helpful for others, and many thanks to peter@pcadynamics.com for the info.

 

Good info Plenty, thanks for sharing.

When I was sorting the PCA Dynamics Blob/hawk WRX Prodrive blues groupbuy Peter said he can reproduce any Prodrive spring as follows:

WR Sport 99

P1 (available via 2pots groupbuy)

Bug STi

early Blob STI (WR1)

wide track (RB320)

US WRX and STi

08 STi etc

He also did some Legacy ones that Subaru UK never took on.

Might be of interest for some further groupbuys

BTW, there were a set of new RB320 Prodive black springs on ebay a few days back offers around £150, not sure if they sold

 

Interested in this spring set for my hawk. Any idea if Peter will offer a group buy?

 

I think he would prefer groupbuys as he doesn't have them sat on a the shelf. He did work out some prices last year from Eibach that were over £300 a set (for 1-4 sets of one specific type) but also has an alternative supplier that worked out lot cheaper.

Might be worth starting a group buy thread and contacting Peter for updated costs

 

Handy info.