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PostPosted: Wed Jul 05, 2006 09:21 
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jamie_duff wrote:
The K-series is basically a race engine assembled carelessly.

It's a very capable powerplant when dealt whith properly.


Flat 4's make a very distinctive noise and this would be immediately obvious. I personally hate the sound in a car (not so bad driving a propellor) but there are loads more people who seem to love it.

Whichever way inclined you are though, it's not a noise you can confuse with an I4. :wink:


i had a 214 on an L plate. it tanked XR3is which surprised me considering they had a reputation behind them whereas i had a 5 door granny car :lol:

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PostPosted: Wed Jul 05, 2006 16:58 
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[shameless plug mode]Going back to insurance prices, I can strongly recommend trying Admiral if this is causing problems. Owning up to big exhaust, air filter, vented front discs, rear disc conversion, lowered suspension and (dealer option) alloys raised the quote on my Puma from £300 to £335, which I thought was very acceptable. Now they're charging me £275 for my Group 17 Clio![/shameless plug mode]


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PostPosted: Wed Jul 05, 2006 17:12 
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Funny that

I found the exact opposite. After being a customer for 3 years they tried to push the Cougar's policy from £450 up to nearly £800 over a set of alloys, so I told them to shove it.

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PostPosted: Wed Jul 05, 2006 19:09 
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Well, I've gone with the 4pot front brake conversion @ £400 fitted and the rear droplinks for £90 fitted. They're also fitting a set of braided hoses that I bought that a different garage were supposed to fit when changing the fluid at the 60K service, but didnt!

Insurance (Hyperformance) want no extra money at all for the brakes, just want a certificate of installation faxing afterwards.

I guess I'll leave the bushes alone, with the possible exception or ARB and steering rack bushes? this will have to be done at another time though.


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PostPosted: Wed Jul 05, 2006 19:45 
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Lum wrote:
I guess I'll leave the bushes alone, with the possible exception or ARB and steering rack bushes? this will have to be done at another time though.


These are OK in poly. In fact Urethane has good abrasion resistance so is ideal for anti roll bar bushes.

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PostPosted: Wed Jul 05, 2006 21:42 
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"Poly" bushes do tend to make most cars noticeably harsher. IF you don't mind the harshness, that's fine but as has been said, natural rubber tends to give the best compromise. If you want really harsh, you could always go to "rose" joints if the suspension design will allow it but they're pretty useless for road work.

The "silly cantilever thing" on the standard brake callipers is partly a cost saving measure but on many cars it is done to allow the wheel spokes to be closer to the disc so that it reduces the wheel offset. This can have big stability benefits in a straight line - particularly should you be unfortunate enough to have a front tyre blow out. Bigger offsets might also make the car pull a bit when you hit standing water on one side. I can only speak in general terms and have no experienec of the Legacy though.

If your pads were wearing unevenly, the callipers (in particular, the slides) were probably knackered and a set of recon. callipers should have sorted it.


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PostPosted: Wed Jul 05, 2006 21:50 
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I have no idea what the rose joints are. I was offered rose jointed droplinks by the garage but insisted on the Whiteline alloy ones. Sounds like I made the right decision.

My Legacy comes as standard with the same wheels as a WRX, only in silver rather than gold, therefore I will not be changing offsets by fitting WRX 4pots. This is also why I haven't gone for STI 4por Brembos :)

Since the callipers needed replacing, I think the WRX ones were a good choice all around. They are far more easy to obtain and dont have to be shipped from Japan.

The uneven pad wear seems to be a common complaint on this car, at least it seems to be on the Legacy forums.

So cheaper and better performing with no insurance hit. Seems like a winner all round to me.

Only remaining concern is will the change to 4pots affect the brake bias. The garage don't seem to think it matters.


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PostPosted: Wed Jul 05, 2006 21:51 
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Lum sir, you have a fastish car, certainly faster than mine. You appear to my simple mind to be adding "go-faster" bits to it. Grandad doesn't fit braided hoses to his Kia Mentor.

So how much use is it? I mean, my car, is quite slow but I can't use all of it's performance on the road. Firstly, though I don't cause many queue's, you can't be too carefull as far as points on licenses go. Secondly if I drive with stopping in the distance I can see to be clear in mind (thinking of NCB this time) I can't go any faster there either.

I don't think my ablity to process the information required to go fast on twisty roads is that good, which may limit my need to make a fast car faster.

Or....do you do track days? In which case too fast is nearly fast enough.


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PostPosted: Wed Jul 05, 2006 22:16 
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The modifications I'm talking about aren't really about "go-faster" additions. In fact surely brakes are a "go-slower" addition, though presumably you mean that since I can stop quicker it will be safer to go quicker in the first place.


This isn't really what I am doing. I am really aiming to replace wear items (such as rubber bushes) with more durable items that I will never have to replace again, and also rectifying design flaws that the car has to save on manufacturing costs.

Case in point, the plastic droplinks are a bloody stupid idea, especially with the state of UK roads. The car is a grey import and they may be just fine on Japanese roads which I imagine will be better maintained than ours.

I am expecting the brake upgrade to pay for itself in the longer term as more even pad wear means the pads will last longer, plus UK WRX pads are cheaper than JDM Legacy pads.

Braided hoses, once again, should last forever wheras rubber hoses will perish. They also reduce the time between you seeing a hazard and braking forces being applied to the wheels. The reason for this is your initial braking force is wasted as the brake fluid causes the rubber hoses to bulge first, then the pistons move later. We are probably talking times of less than a second here but it could make all the difference.

Overall, my Legacy has almost as much power as a UK WRX STI 260 vs 265 bhp) but currently has brakes that are worse than the vanilla WRX and on a heavier car to boot. I think brakes are a very worthwhile upgrade.


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PostPosted: Thu Jul 06, 2006 12:30 
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The primary reason for the change from the plastic to drop-links to the poly-bushes on solid drop links is to reduce the slack before the Anti-roll bar is twisted, and hence reduce body roll during cornering - in particular at the back. By reducing body roll more front tyre grip is maintained thus reducing under-steer and giving a nice direct turn in, but also making the car over-steer more when it is so inclined. As the bushes are only connected to the ARB it doesn't affect ride at all, just body roll. Also consider a stiffer ARB such as the whiteline adjustable one that is so popular.

Lum if your car is over-steering more than you want check your tyre pressures as Subaru handling is very sensitive to tyre pressure.

I am also considering a few other little mods - Prodrive or Eibach springs, and larger disks on mine, neither of which should affect the Warranty. Braided hoses are a possibility if you experience brake fade, but I haven't been on the track yet and haven't noticed anything to justify it - they reduce the ability of the hose part of the brake system to expand under pressure and give a better brake response. Powerstation are not to far away from me, so I might get some expert advice - they make some of the fastest ones around in partnership with their next door neighbours Litchfield Imports who are the biggest importers of really high performance Imprezas (same building actually).

Getting insurance for PPP is not so easy and you can forget most of the big names - I am currently with Keith Michaels (a specialist) after Liverpool Victoria kept increasing the premiums. Saved over £200 this year by switching. KM is a broker, but one of their staff is a keen Impreza owner and is active on Scoobynet, and they are happy for you to call him directly - because he knows exactly what car you are dealing with it is very easy to explain: "2004 Impreza WRX with PPP, Quickshift and CD Changer" was all I needed rather than the loads of explanation everybody else needed.


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PostPosted: Thu Jul 06, 2006 21:42 
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Well, I have the car back. The garage are rather impressed with the whiteline droplinks they ordered for me, apparently they're rose jointed and rather big. They said they're going to keep them in stock.

My random oversteer is gone, the car is back to understeering, so I think I'm going to have to play with the front suspension a bit now. Thinking about it, the oversteer was usually in conjunction with a bump so it probably wasn't gripping properly at the back, hencr random oversteer.

Dont know if the brakes are any good yet, I have to be gentle for 200 miles.


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PostPosted: Thu Jul 06, 2006 22:37 
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Ok, was going to mention "rose" joints but I guess you'll have seen some by now so there's not much point!

Also, rubber brake hose swelling is definitely a known phenomenon and definitely increases the amount of time to reach a given clamping force but I think it is measured in milliseconds rather than seconds or even tenths of a second! It's true that natural rubber brake hoses perish but it is a gradual process and the deterioration is visible on the outer casing long before it is likely to become a problem on the inner hose. The same can't be said for the braided ones - they have been known to get the internal plastic liner kinked without showing much evidence of damage on the outer braiding. Maybe the most important benefit is the accuracy with which you can modulate braking effort with braided hoses. The same lag that delays brake application with rubber hoses also delays any lessening of braking effort by a similar amount. Although I'm nowhere near a good enough driver for it to make a difference, some racing drivers can exploit this!

One issue that could be become a problem is the phasing of the ABS pulses. The frequency with which the ABS pump cycles the pressure will have been calculated so as not to be a harmonic of the frequency of the swelling in the rubber hoses. Obviously, the braided ones will have different characteristics. I'm not sure how (if at all) this would affect things but to give some idea, when we modify a vehicle at work to take a wheelchair, the base vehicle manufacturer generally doesn't like us to change the length of any of the rigid pipes under the car by more than a few hundred mm for the same reason - altering the frequency at which the wheels cycle.

You've already mentioned brake balance so you're obviously aware of the potential consequences of that!

The only other thing is being gentle with the brakes for a few hundred miles. Unless you've been specifically told to do this by the pad / disc manufacturers, it might not be the best thing to do. Too gentle a life in the early days can sometimes "glaze" the brakes and they don't perform as well as they should. This is quite a good article on it:

http://www.stoptech.com/tech_info/wp_bedintheory.shtml


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PostPosted: Thu Jul 06, 2006 22:46 
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I haven't actually seen the rose joints yet, it was dark when I got home, so I didn't bother to crawl under the car and have a peek.

I would hope that the braided hose issues you talk about will have been taken into account by the manufacturer. Goodridge are a well respected maker of such hoses and they are sold specifically for 98-99 import Legacy B4s. If they're not compatable with the ABS then they have a product liability or corporate manslaughter issue on their hands.

I mentioned brake balance only because the garage told me not to worry about it. I guess going from 2 pot cantilever things to 4 pots doesn't affect the braking forces that much. What signs should I be looking for if there is a problem?

I suppose if the balance is out then I should replace the rear single pots with 2pots, of a kind where one piston is on each side. I must check to see if the WRX has these as standard as WRX rears in addition to the WRX fronts would presumably put the balance back as they're designed to be used together.

I've not been mega gentle granny-in-a-Micra with the brakes. They have just seen a run through Milton Keynes with a fair few 70-0 stops, I just haven't been leaving them as late and not applying full force. Hopefully this will be sufficient.


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PostPosted: Thu Jul 06, 2006 22:54 
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Lum wrote:
My random oversteer is gone, the car is back to understeering, so I think I'm going to have to play with the front suspension a bit now. Thinking about it, the oversteer was usually in conjunction with a bump so it probably wasn't gripping properly at the back, hencr random oversteer.


As in 'hopping' or 'skipping' at the back?

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PostPosted: Thu Jul 06, 2006 23:04 
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SafeSpeed wrote:
As in 'hopping' or 'skipping' at the back?


Possibly, it's hard to tell for certain. It wasn't a smooth 3fast3furious drift or anything like that, so I guess you're right.


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PostPosted: Fri Jul 07, 2006 08:54 
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Are you sure that the shocks are OK - worn shocks will increase the bounce over bumps, and might lead to the over-steer, but the more rigid ARB set-up you now have will transfer a little movement/damping to the other side and reduce the effect.

2002 onwards Imprezas have 4 pot front, 2 pot rears, unless upgraded. If your are serious about stopping, then you can go to 4 pot rear and 6 pot front with significantly larger disks, but a much cheaper change to a higher performance pad type and better disks will also improve things. Just don't go for the racing spec pads because they don't work when cold!


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PostPosted: Fri Jul 07, 2006 11:07 
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Farily sure my shocks are ok. They pass the used car buying, push down on each corner test, and they wern't advised as being faulty at the 60K service.

I haven't replaced the ARBs, just the droplinks (which were advised), and now the problem has gone away, so I guess it's all right.

As for stopping, I think these brakes are the biggest that wsill fit under my 17" WRX wheels. They came from a 2000 impreza so presumably I'd want rears from the same car if braking becomes a problem


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PostPosted: Fri Jul 07, 2006 23:28 
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Lum wrote:
I haven't actually seen the rose joints yet, it was dark when I got home, so I didn't bother to crawl under the car and have a peek.

I would hope that the braided hose issues you talk about will have been taken into account by the manufacturer. Goodridge are a well respected maker of such hoses and they are sold specifically for 98-99 import Legacy B4s. If they're not compatable with the ABS then they have a product liability or corporate manslaughter issue on their hands.

I mentioned brake balance only because the garage told me not to worry about it. I guess going from 2 pot cantilever things to 4 pots doesn't affect the braking forces that much. What signs should I be looking for if there is a problem?

I suppose if the balance is out then I should replace the rear single pots with 2pots, of a kind where one piston is on each side. I must check to see if the WRX has these as standard as WRX rears in addition to the WRX fronts would presumably put the balance back as they're designed to be used together.

I've not been mega gentle granny-in-a-Micra with the brakes. They have just seen a run through Milton Keynes with a fair few 70-0 stops, I just haven't been leaving them as late and not applying full force. Hopefully this will be sufficient.


"Rose" is a trade name but is almost universally used to describe "sperical" bearings. Basically a sphere (albeit with a hole though the middle) pressed into a housing so that it acts as a balljoint. They are often used to replace rubber bushes where people want sharper responses and don't mind increased harshness.

I take your point about the brake hoses and liability but personally I wouldn't like to be the one fighting the claim against a company that big! Is it possible that Goodridge only make the material but another company cuts it to length and crimps the ends on to sell it for the car application?

No way of telling how much the braking force has been affected. Typically, the main things that affect it are piston diameter, disc diameter, effective pad centre position (i.e. the distance out from the centre of rotation that the retarding force is applied) and the coefficient of friction between the disc and the pad. It is further complicated by the fact that the friction between the pad and disc changes with temperature! As for signs of imminent trouble, again it depends...
...If the alteration had made the front brakes do an unusually large proportion of the braking, probably nothing will be noticed. You just won't be getting the full benefit of what the rears could have contributed. If it makes the rears do too much braking, on a non-ABS car, you might notice that you have to look in your mirror to see where you are going! :shock: If the rears lock up first, there's a likelihood that the car could spin. As it has ABS, I'd expect the ABS to prevent the rear wheels from locking so HOPEFULLY, nothing terrible will happen but the ABS might cut in on the rears more often. If it has electronic stability control, I haven't a clue what it might do! I guess the best thing would be to talk to other people who have done the same mod and see if there are any known issues peculiar to that car.

Impossible to say whether doing the same thing to the rears will make things better, worse or about the same.


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PostPosted: Fri Jul 07, 2006 23:41 
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As far as I'm aware, Goodridge make the hose, complete with fittings and test them on the cars that they are sold for. My kit is for Legacy B4s from 98-99. I queried this with them as 98 cars used the BG5 chassis and in August 99 they switched to the BE5 chassis which I have. They said it would work with both, so I asked why it didn't say 98-03 (when thy stopped making BE5s) and they said it was because they didn't have any 2000 Legacies to test with so they didn't want to say it would work.

I did have to fit bigger discs to fit these brakes and I imagine that since there are 2 more pistons now, the effective diameter has increased, unless the cantilever counts as two extra pistons for the purposes of this calculation.

Most people who have done this have gone for STI Brembos rather than WRX 4pots, however that would've meant going to 18" wheels and losing the subtlety of my car. You don't buy a Legacy if you want bling :)


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