Prodrive P1 Lowering Springs - Rare Purchase opportunity.
Scooby Regular
Joined: Feb 2015
Posts: 56
Likes: 0
From: Canada
Received the springs and bump stops few days ago, so excited to put them on. I got your PM 2pot and I will follow your instructions regarding the bump stop install.
Now, I'm pretty sure I read this on the thread, the koni yellows are TT so the bump stop I got will work with it?
Now, I'm pretty sure I read this on the thread, the koni yellows are TT so the bump stop I got will work with it?
Received the springs and bump stops few days ago, so excited to put them on. I got your PM 2pot and I will follow your instructions regarding the bump stop install.
Now, I'm pretty sure I read this on the thread, the koni yellows are TT so the bump stop I got will work with it?
Now, I'm pretty sure I read this on the thread, the koni yellows are TT so the bump stop I got will work with it?
The stops you've got will be fine with koni's.
Scooby Regular
Joined: Oct 2011
Posts: 207
Likes: 0
From: SE Wales
Satellite delay - thanks. I started a new job so I'm only getting round to fitting these now. I've check to make sure all the bolts will undo, they will so will crack on an order my shocks (with shiney new camber bolts!).
Cheers.
Cheers.
Make sure you get the cone washers, cone side up.
http://www.dirtyimpreza.com/forums/s...cal-Washer-FAQ
Make sure you get the 3 holes on the front, upper spring perch, facing to the outside of the car.
The outer, middle of the 3 holes, should line up, vertically, in-between the two lower strut mounting brackets.
Lastly, there are 3 small, semi-circular notches cut in the rear, upper spring perches.
Looking at the rear perch, with the middle notch in the in the 6 O'clock position, the notch to the left should line up, vertically, in-between the two lower strut mounting brackets, when fitting the left-hand strut.
Conversely, the notch to the right, of the middle notch, should line up, vertically, in-between the two lower strut mounting brackets, when fitting the right-hand strut.
That's left and right as if you were sitting in the car.
HTH
http://www.dirtyimpreza.com/forums/s...cal-Washer-FAQ
Make sure you get the 3 holes on the front, upper spring perch, facing to the outside of the car.
The outer, middle of the 3 holes, should line up, vertically, in-between the two lower strut mounting brackets.
Lastly, there are 3 small, semi-circular notches cut in the rear, upper spring perches.
Looking at the rear perch, with the middle notch in the in the 6 O'clock position, the notch to the left should line up, vertically, in-between the two lower strut mounting brackets, when fitting the left-hand strut.
Conversely, the notch to the right, of the middle notch, should line up, vertically, in-between the two lower strut mounting brackets, when fitting the right-hand strut.
That's left and right as if you were sitting in the car.
HTH
I've had mine on for about a month. I have the Prodrive Bilsteins which had the blue springs. All I can say is these P11Ls feel pretty much the same as the blues, with the added advantage of a few extra mm on the rear ride height (it's a wagon). So I'm very pleased.
After fitting, drive the car on and off the ramps, then torque up the suspension with the full car weight on it - ensure full tank of fuel.
I'd then potter around for at least 4 days (some prefer 10 miles of stick), then get an alignment - again, full tank of fuel, and you, or your weight, in the driver's seat.
Make sure you get the re-check/re-alignment, in a month (again, full tank), as part of the alignment deal.
Scooby Regular
Joined: Oct 2011
Posts: 207
Likes: 0
From: SE Wales
Fitted mine about three weeks ago and alignment done a week later. Since then it's covered about 400 miles. Less soft than the originals, I have set my ARB on the back to the stiffest setting (it's a 24mm Whiteline ARB) and now I like the feel better. The photo was taken at Castle Combe.
Fitted mine about three weeks ago and alignment done a week later. Since then it's covered about 400 miles. Less soft than the originals, I have set my ARB on the back to the stiffest setting (it's a 24mm Whiteline ARB) and now I like the feel better. The photo was taken at Castle Combe.
For my database.
Distance from wheel centre, front and rear, vertically up to arch, both sides, please.
What struts and fuel level?
Thanks
Fitted mine about three weeks ago and alignment done a week later. Since then it's covered about 400 miles. Less soft than the originals, I have set my ARB on the back to the stiffest setting (it's a 24mm Whiteline ARB) and now I like the feel better. The photo was taken at Castle Combe.
P11L spring sets:
16 sets left, from the original 50.
P1 spring rates
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.
6mm lower front ride height than P1 springs:
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 sta 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.
The P1 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.
Updated bump stops are available for inverted and twin-tube dampers
P11L spring set - £235 delivered GB and NI
WR15R/T spring set:
If you need something stiffer/6mm lower, than the P11L's:
Smooth, flat roads or track days - 40N/mm front, 35N/mm rear - almost identical rates to the v5/v6 sti.
WR15R/T spring set - £290 delivered GB and NI
16 sets left, from the original 50.
P1 spring rates
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.
6mm lower front ride height than P1 springs:
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 sta 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.
The P1 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.
Updated bump stops are available for inverted and twin-tube dampers
P11L spring set - £235 delivered GB and NI
WR15R/T spring set:
If you need something stiffer/6mm lower, than the P11L's:
Smooth, flat roads or track days - 40N/mm front, 35N/mm rear - almost identical rates to the v5/v6 sti.
WR15R/T spring set - £290 delivered GB and NI
Last edited by 2pot; Oct 2, 2015 at 01:05 PM.
Got my P11L springs fitted a few months back and chose Pedders Sport Ryder shocks. Car: UK MY00 turbo.
Unfortunately I didn't take measurements of the car on its standard suspension; now the distances from centre of wheel to arch are:
O/S N/S
Front 337 335 mm
Rear 337 335 mm
The ground is slightly sloping which probably explains the difference between N/S and O/S.
Fuel level: almost full.
Front before
Front after
Rear before
Rear after
Guess what other change I made!
Unfortunately I didn't take measurements of the car on its standard suspension; now the distances from centre of wheel to arch are:
O/S N/S
Front 337 335 mm
Rear 337 335 mm
The ground is slightly sloping which probably explains the difference between N/S and O/S.
Fuel level: almost full.
Front before
Front after
Rear before
Rear after
Guess what other change I made!
Last edited by Nick_Cat; Oct 31, 2015 at 02:39 PM.
Got my P11L springs fitted a few months back and chose Pedders Sport Ryder shocks. Car: UK MY00 turbo.
Unfortunately I didn't take measurements of the car on its standard suspension; now the distances from centre of wheel to arch are:
O/S N/S
Front 337 335 mm
Rear 337 335 mm
The ground is slightly sloping which probably explains the difference between N/S and O/S.
Fuel level: almost full.
Front before
Front after
Rear before
Rear after
Guess what other change I made!
Unfortunately I didn't take measurements of the car on its standard suspension; now the distances from centre of wheel to arch are:
O/S N/S
Front 337 335 mm
Rear 337 335 mm
The ground is slightly sloping which probably explains the difference between N/S and O/S.
Fuel level: almost full.
Front before
Front after
Rear before
Rear after
Guess what other change I made!
The feed-back is really helpful.
A full, side-on, image would be nice, again with fuel level.
May be the 215/45 x 17 tyres are making it look lower? Less arch gap.
The P11L's are all coming out about 335mm front height. Which was the front ride height of the Prodrive WR97/98 Bilstein/Eibach spring kit.
The P11L rears vary with fuel load (and, occasionally, strut dimensions): 340 +/- 5mm, is the current average (335 +/- 5mm on the wagon).
This was the intention - positive rake (and a bump stop change) neutralising undesteer, without resorting to a bigger rear bar.
My mantra:
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 sta 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.
As to how it drives, I was surprised. He said it was surprisingly comfortable! I must have got the bump stop set-up right.
Have you managed to measure your P1 + WR99 ride heights yet (fuel level?)? I believe the wr99 rears lifted it 5/6mm, over the inverted KYB's you had previously?
The P11L's are all coming out about 335mm front height. Which was the front ride height of the Prodrive WR97/98 Bilstein/Eibach spring kit.
The P11L rears vary with fuel load (and, occasionally, strut dimensions): 340 +/- 5mm, is the current average (335 +/- 5mm on the wagon).
This was the intention - positive rake (and a bump stop change) neutralising undesteer, without resorting to a bigger rear bar.
My mantra:
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 sta 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.
As to how it drives, I was surprised. He said it was surprisingly comfortable! I must have got the bump stop set-up right.
Have you managed to measure your P1 + WR99 ride heights yet (fuel level?)? I believe the wr99 rears lifted it 5/6mm, over the inverted KYB's you had previously?
Last edited by 2pot; Nov 6, 2015 at 09:49 PM.
That car does look lower than most - into the over-lowered area. Tyres, maybe.
My Type R ('P1') which was a similar height and it was pretty much on the stops. Drove horribly - understeered and crashed on hard hits
Your mantra is fine - more than one way to skin a cat as they say
As you know, I have 22/24 bars on my classic and I can't imagine it driving any better
Only been out in it a couple of times (been suspension fettling mt Forester STi so that sees the days out jollies) and forgot to measure. I will though
My Type R ('P1') which was a similar height and it was pretty much on the stops. Drove horribly - understeered and crashed on hard hits
Your mantra is fine - more than one way to skin a cat as they say
As you know, I have 22/24 bars on my classic and I can't imagine it driving any better
Only been out in it a couple of times (been suspension fettling mt Forester STi so that sees the days out jollies) and forgot to measure. I will though