P1/STi Red Shock, Bilstein WR Shock, P1 Red Springs & WR Blue Springs Discussion
#121
#122
It would appear that this washer is only there to stop the gaiter sliding down the damper too far, as the hole in the gaiter is almost the same size as the flange on the top of the damper shaft.
Last edited by Scott.T; 25 January 2015 at 07:40 PM.
#123
Scooby Regular
iTrader: (3)
Assessed all the springs discussed previously, and ended up with these Eibach designs:
P11L spring set:
Linear rate in their operational range.
Material and design updates, mean each front spring is now 600 grams lighter, than original P1's.
Longer front spring free-length (P1 v P11L below). Now allows safe usage, in struts other than kyb inverted. No dislodging at full droop.
Front ride height same as WR97/98 springs.
The P1 & v5/6 sti had very stiff front bump stops in the inverted struts, as a form of pitch control. But this can give a bobbing ride sensation and understeer, on anything but flat, smooth roads.
The handling can be made more neutral, again, without increasing the rear bar diameter, with shorter, progressive front stops and stiffer rear stops.
Matching, updated, bump stops are available for inverted and twin-tube dampers.
P1 front v P11L front
WR15R/T spring set:
If you need something stiffer than the P11L's - Ideal on smooth, flat roads or track days - 40N/mm front, 35N/mm rear. Ground top coils, almost identical rates to the v5/v6 sti, but lowered, with additional positive rake.
On a road car, instead of using bigger bars, to achieve a more neutral balance, adding additional positive rake and matching bump stops is often a better way.
Bigger bars add additional wheel rate, that must be controlled by the dampers - that were never specified for it. And it's not just during cornering -
there's no such thing as a flat road.
The top chassis has positive rake, although the larger front arch profile makes it look negative.
The lower chassis has 10mm more positive rake.
Here's how positive rake was used, by Prodrive, on the RB320:
A, relatively, higher rear ride height, moves the roll centre rearward, increasing rear roll resistance.
That, in turn, makes the front end roll more - helping turn-in response and reducing understeer, without the use of stiffer bars.
You want the smallest bars possible, on a road car, to avoid 'roll-rock'.
Roll-rock:
If the spring rate is relatively low and the bar is too stiff, a suspension movement, initially, occurring on only one side of the vehicle, will be transmitted to the other side, inducing an unsettling 'roll-rock' motion.
Group buy:
https://www.scoobynet.com/991887-pro...tunity-14.html
P11L spring set:
Linear rate in their operational range.
Material and design updates, mean each front spring is now 600 grams lighter, than original P1's.
Longer front spring free-length (P1 v P11L below). Now allows safe usage, in struts other than kyb inverted. No dislodging at full droop.
Front ride height same as WR97/98 springs.
The P1 & v5/6 sti had very stiff front bump stops in the inverted struts, as a form of pitch control. But this can give a bobbing ride sensation and understeer, on anything but flat, smooth roads.
The handling can be made more neutral, again, without increasing the rear bar diameter, with shorter, progressive front stops and stiffer rear stops.
Matching, updated, bump stops are available for inverted and twin-tube dampers.
P1 front v P11L front
WR15R/T spring set:
If you need something stiffer than the P11L's - Ideal on smooth, flat roads or track days - 40N/mm front, 35N/mm rear. Ground top coils, almost identical rates to the v5/v6 sti, but lowered, with additional positive rake.
On a road car, instead of using bigger bars, to achieve a more neutral balance, adding additional positive rake and matching bump stops is often a better way.
Bigger bars add additional wheel rate, that must be controlled by the dampers - that were never specified for it. And it's not just during cornering -
there's no such thing as a flat road.
The top chassis has positive rake, although the larger front arch profile makes it look negative.
The lower chassis has 10mm more positive rake.
Here's how positive rake was used, by Prodrive, on the RB320:
A, relatively, higher rear ride height, moves the roll centre rearward, increasing rear roll resistance.
That, in turn, makes the front end roll more - helping turn-in response and reducing understeer, without the use of stiffer bars.
You want the smallest bars possible, on a road car, to avoid 'roll-rock'.
Roll-rock:
If the spring rate is relatively low and the bar is too stiff, a suspension movement, initially, occurring on only one side of the vehicle, will be transmitted to the other side, inducing an unsettling 'roll-rock' motion.
Group buy:
https://www.scoobynet.com/991887-pro...tunity-14.html
Last edited by 2pot; 10 January 2016 at 02:18 PM.
#127
Scooby Regular
iTrader: (3)
As previously discussed with 'Sad Weevil': The rear Bilstein WR97/98 strut housing (not WR97/98 springs), are shorter than all other Classic Impreza rear struts.
Only, when using rear Bilstein WR97/98 struts, on a wagon (35kg of extra rear weight) with P11L's, is a 6/10mm rear spacer required.
A spacer is not required, with any other combination of Classic strut and P11L spring - whether that be GC8, GF8 or GM8.
Last edited by 2pot; 19 January 2016 at 09:22 PM.
#128
Yep, that sums it up.
The Prodrive WR suspension (Bilsteins with WR springs) sit lower then the P1/STi struts and P1 springs. This is what I am trying to achieve.
As a side effect of this investigation, and using our source for spring manufacture we may end up with a combination of springs for a combination of strut types.
Most agree that the Tein's don't perform well, the Eibach-Pro hardly lower the car (especially STi models) and are rated too soft (I found front end dive quite bad on these when hard/emergency braking).
As mentioned elsewhere, although the P1 springs are quoted as 'lowering' they do very little or anything when compared to an STi (only 7mm lower at the back compared to Eibach-Pro on my car). So people that are unhappy with the stance of the Eibach-Pro would be equally unhappy with the P1 Red.
This thread is therefore about finding an alternative to the ever reducing MacPherson strut coil spring market for a classic impreza, and maybe providing small scale production of such items.
The Prodrive WR suspension (Bilsteins with WR springs) sit lower then the P1/STi struts and P1 springs. This is what I am trying to achieve.
As a side effect of this investigation, and using our source for spring manufacture we may end up with a combination of springs for a combination of strut types.
Most agree that the Tein's don't perform well, the Eibach-Pro hardly lower the car (especially STi models) and are rated too soft (I found front end dive quite bad on these when hard/emergency braking).
As mentioned elsewhere, although the P1 springs are quoted as 'lowering' they do very little or anything when compared to an STi (only 7mm lower at the back compared to Eibach-Pro on my car). So people that are unhappy with the stance of the Eibach-Pro would be equally unhappy with the P1 Red.
This thread is therefore about finding an alternative to the ever reducing MacPherson strut coil spring market for a classic impreza, and maybe providing small scale production of such items.
This is my ride height on Bilsteins & P1 springs:
Last edited by AncientRS; 23 July 2016 at 09:19 PM.
#129
Scooby Regular
iTrader: (3)
Scott is discussing the WR97/98 Bilsteins, which had a shorter rear housing and lower ride height springs.
New WR99 Bilsteins are 6mm taller at the rear, than new v6sti dampers, when using the same P1 springs - due to static gas pressure.
Question is: How much is your current ride height due to loss of static gas pressure, over the years?
Officially, the v6sti dampers, with P1 springs, had a front wheel centre to arch gap of 341mm (13" 7/16), on a turbo car. Don't know how much lighter a GC6 is at the front?
Bonesetter's car:
P1's + WR99
P1's + Subaru inverted (V5sti/V6sti/P1)
Fuel can make a 10mm difference in ride height (full to empty) on a P1 spring.
New WR99 Bilsteins are 6mm taller at the rear, than new v6sti dampers, when using the same P1 springs - due to static gas pressure.
Question is: How much is your current ride height due to loss of static gas pressure, over the years?
Officially, the v6sti dampers, with P1 springs, had a front wheel centre to arch gap of 341mm (13" 7/16), on a turbo car. Don't know how much lighter a GC6 is at the front?
Bonesetter's car:
P1's + WR99
P1's + Subaru inverted (V5sti/V6sti/P1)
Fuel can make a 10mm difference in ride height (full to empty) on a P1 spring.
Last edited by 2pot; 23 July 2016 at 01:03 PM.
#130
Good questions. I didn't record the heights when they were put on 9 years ago, and I have no idea how much the front weight difference is between the turbo models & the USDM 2.5RS.
I also carry a full-size 16" wheel and tools in the trunk; perhaps I'll just keep the fuel tank half-empty.
I also carry a full-size 16" wheel and tools in the trunk; perhaps I'll just keep the fuel tank half-empty.
#131
Scooby Newbie
Join Date: Dec 2016
Location: Nice - Fr
Posts: 22
Likes: 0
Received 0 Likes
on
0 Posts
Hello Everybody,
I've just join the forum
This thread is simply amazing Thanks a lot for your job !
And perfect for me as I need to put good springs on my car (Wagon 98)
My struts are quite good (freshly refurbished/revalved Ohlins inverted)
but my rake, my ride height, and spring rates are horrible
I am going to see the GB thread right now...
I've just join the forum
This thread is simply amazing Thanks a lot for your job !
And perfect for me as I need to put good springs on my car (Wagon 98)
My struts are quite good (freshly refurbished/revalved Ohlins inverted)
but my rake, my ride height, and spring rates are horrible
I am going to see the GB thread right now...
#132
Hello, I'm back into a classic after a period away and I have a nice 1996 V2 WRX STi Version
I have some brand new P1 struts and I'm looking for a set of springs. I've been looking at Pink STi spring sets and also been reading through this and other threads.
I was interested in the discussion around bump stops as using the STi pink springs there is no uprated bumpstop listed on Subarus database and the assumption is that you reuse your existing stops.
So I guess I have 2 questions. Firstly are the WR15R/T spring sets comparable to the STi spring sets ? and secondly are you recommending corresponding bumpstops for the WR15R/T spring set when used with the P1 Struts if so could they be used with the STi Pink springs. Apologies if the answer is already in this thread. I read and digested as much as possible but not everything went in I'm sure.
I already have New age pink rear arms which has added some welcome camber and I will be using possibly the newage 21mm adjustable rear arb or larger 22/24 front and rear I haven't decided. I also have newage wheels fitted 17x7.5.
I'm not looking for comfort and the car will be driven hard
I have some brand new P1 struts and I'm looking for a set of springs. I've been looking at Pink STi spring sets and also been reading through this and other threads.
I was interested in the discussion around bump stops as using the STi pink springs there is no uprated bumpstop listed on Subarus database and the assumption is that you reuse your existing stops.
So I guess I have 2 questions. Firstly are the WR15R/T spring sets comparable to the STi spring sets ? and secondly are you recommending corresponding bumpstops for the WR15R/T spring set when used with the P1 Struts if so could they be used with the STi Pink springs. Apologies if the answer is already in this thread. I read and digested as much as possible but not everything went in I'm sure.
I already have New age pink rear arms which has added some welcome camber and I will be using possibly the newage 21mm adjustable rear arb or larger 22/24 front and rear I haven't decided. I also have newage wheels fitted 17x7.5.
I'm not looking for comfort and the car will be driven hard
#133
Scooby Regular
iTrader: (9)
You have brand new bumpstops in your brand new dampers
You may want to consider changing them, or just trimming them, but they will work fine with the springs you are considering
I have the same on my 'P1' with a 22/24 bar combo and it is brilliant for hooning A/B roads
You may want to consider changing them, or just trimming them, but they will work fine with the springs you are considering
I have the same on my 'P1' with a 22/24 bar combo and it is brilliant for hooning A/B roads
#134
Scooby Regular
iTrader: (3)
The P1/v5st/v6sti front stops are 60mm and too stiff (designed as a form pitch control on smooth Japanese roads).
The rear stops are 84mm and too soft.
If you change the stops (shorter more progressive front with shorter stiffer rears) you change the car balance away from understeer - without having to resort to big bars, which reduce grip, braking and suspension independence. This is nothing new, the original P1 suspension designer, latterly, did a bump stop kit, for the same reasoning.
The rear camber you've added, in isolation, increases understeer.
The wr15r/t springs (230/200lb/in) are similar in rate to the V6sti (237/195lb/in) springs. But, lower, with more forward rake, again, to reduce understeer without big bars. The V6sti used the same struts, as the ones you purchased.
I'd try the wr15r/t springs and bump stops with 19mm front and 20mm rear bars, first. The increased rake and bump stops should be enough (unless you're on track?).
If you want some top mount, bush, alignment info PM me.
Be advised, the wr15r/t springs are track day/smooth road biased. The P11L springs are b-road biased - more compliant, less steering corrections on uneven undulating roads. The P11L also work with your struts.
The rear stops are 84mm and too soft.
If you change the stops (shorter more progressive front with shorter stiffer rears) you change the car balance away from understeer - without having to resort to big bars, which reduce grip, braking and suspension independence. This is nothing new, the original P1 suspension designer, latterly, did a bump stop kit, for the same reasoning.
The rear camber you've added, in isolation, increases understeer.
The wr15r/t springs (230/200lb/in) are similar in rate to the V6sti (237/195lb/in) springs. But, lower, with more forward rake, again, to reduce understeer without big bars. The V6sti used the same struts, as the ones you purchased.
I'd try the wr15r/t springs and bump stops with 19mm front and 20mm rear bars, first. The increased rake and bump stops should be enough (unless you're on track?).
If you want some top mount, bush, alignment info PM me.
Be advised, the wr15r/t springs are track day/smooth road biased. The P11L springs are b-road biased - more compliant, less steering corrections on uneven undulating roads. The P11L also work with your struts.
Last edited by 2pot; 27 January 2017 at 10:39 AM.
#135
Hi everyone,
I'm after some advice about suspension.
I have a 2000 WR Prodrive with the Prodrive upgraded suspension kit- bilstein dampers and eibach springs.
This was standard on the car when it underwent its transformation from standard classic UK turbo to WR Prodrive at new.
I would like to refresh the suspension and I hear the Bilstein dampers are
rare and unavailable now.
Has anyone had their dampers refreshed by Bilstein?
What other parts should I source? Poly bushes,ARB's,top mounts etc?
I'd like to keep the standard spec on damping and springs but refresh and upgrade all other parts if possible.
I would be very interested in everyone's opinions.
The car has done around 70K
thank you
I'm after some advice about suspension.
I have a 2000 WR Prodrive with the Prodrive upgraded suspension kit- bilstein dampers and eibach springs.
This was standard on the car when it underwent its transformation from standard classic UK turbo to WR Prodrive at new.
I would like to refresh the suspension and I hear the Bilstein dampers are
rare and unavailable now.
Has anyone had their dampers refreshed by Bilstein?
What other parts should I source? Poly bushes,ARB's,top mounts etc?
I'd like to keep the standard spec on damping and springs but refresh and upgrade all other parts if possible.
I would be very interested in everyone's opinions.
The car has done around 70K
thank you
Last edited by WR Prodrive; 12 February 2017 at 02:29 PM.
#137
Scooby Regular
iTrader: (3)
Hi everyone,
I'm after some advice about suspension.
I have a 2000 WR Prodrive with the Prodrive upgraded suspension kit- bilstein dampers and eibach springs.
This was standard on the car when it underwent its transformation from standard classic UK turbo to WR Prodrive at new.
I would like to refresh the suspension and I hear the Bilstein dampers are
rare and unavailable now.
Has anyone had their dampers refreshed by Bilstein?
What other parts should I source? Poly bushes,ARB's,top mounts etc?
I'd like to keep the standard spec on damping and springs but refresh and upgrade all other parts if possible.
I would be very interested in everyone's opinions.
The car has done around 70K
thank you
I'm after some advice about suspension.
I have a 2000 WR Prodrive with the Prodrive upgraded suspension kit- bilstein dampers and eibach springs.
This was standard on the car when it underwent its transformation from standard classic UK turbo to WR Prodrive at new.
I would like to refresh the suspension and I hear the Bilstein dampers are
rare and unavailable now.
Has anyone had their dampers refreshed by Bilstein?
What other parts should I source? Poly bushes,ARB's,top mounts etc?
I'd like to keep the standard spec on damping and springs but refresh and upgrade all other parts if possible.
I would be very interested in everyone's opinions.
The car has done around 70K
thank you
The complete wr99 Prodrive kit had grey 35N/mm springs front and rear, with a 19mm front bar and 18mm rear bar.
I'd use Whiteline kca335 front top mounts and 20370AA240 STI/RA rear top mount:
http://www.importcarparts.co.uk/parts-info.asp?id=5930
Thread
Thread Starter
Forum
Replies
Last Post
Scott@ScoobySpares
Full Cars Breaking For Spares
55
05 August 2018 07:02 AM
Mattybr5@MB Developments
Full Cars Breaking For Spares
38
17 July 2016 10:43 PM
ATWRX
Full Cars Breaking For Spares
88
01 February 2016 07:28 PM