Monday, January 2, 2012

Coilover Dampers for the Slowtra - The Euros Part 1 (The Germans)

Happy New Year Everyone!!! Let's start 2012 with the long awaited post on Euro coilovers for the Slowtra beginning with the Germans. Achtung!

AP
AP Sportfahrwerke GmbH is not the same as the famed AP Racing brake manufacturer and supposedly hails from Germany. "Sportfahrwerke" literally translates to "Sport Suspension" in Engrish. AP claim in their website to have been selling superior quality suspension kits for the last ten years. AP make a range of suspension including springs and non-coilover shocks for the Euro N16 the "Almera" but for this post will only be on the coilover range simply called the "AP coilover suspension kit. There is a newer independent height and rebound adjustable coilover known as the "APX" but I cannot confirm if this is available for the N16. I also cannot confirm if the coilovers are mono or twin tube though from pictures shown it looks to be twin tube. AP's website is not very helpful at all and is lacking in technical details.
  • Part Number: GF85-001
  • Damping Adjustable: No. Damping is fixed at factory and claimed to be 25% stiffer than stock but as there are no rates nor damper dyno plots available I'll take this with a pinch of salt.
  • Ride height adjustable: Yes. AP claim you can lower by as much as 30-55mm, Independent Ride height adjustable: No so if you lower too much you will alter spring preload and damping.
  • Rebuildable: Not stated
  • Front Spring Rate: Not known, Rear Spring Rate: Not known. AP specs the coilovers according to vehicle weight which for the N16 is 1010kg front axle load and 970kg rear axle load.
  • Top Mounts: Use back the stock rubber top mounts
  • Other Notable Features:  TÜV certified according to AP. Looks to be a conventional threaded steel body coilover damper with an aluminium spring collar perch. From the pictures on their website AP utilises helper springs.
  • Price is relatively cheap at around 500 or so British Pounds or around RM2.5K not including shipping and tax. AP claim to offer quality and performance comparable to another popular German aftermarket suspension manufacturer Weitec a lower price. However looking at the specs and the lack of any local distributor/support I would recommend the Taiwanese or Japanese coilovers if you do track days rather than car shows
KW
KW Automotive GmbH also from Germany is currently one of the most popular race/performance/track day suspension manufacturer and produce a range of coilover dampers from the simple non-adjustable Variant 1 coilover to really serious motorsport stuff with equally serious price tags. For the N16 and USDM B15 it's either the top of the range or the bottom. An email enquiry to KW on whether they would make a Variant 3 or Clubsport for the N16 as resulted in an expected "No" reply. At least KW responded to my email. Let's start with the bottom of the range Variant 1 twin tube coilover damper.
  • Part Number: 05285001 (not stated in KW's catalogue but I got the same part number from several websites selling the KW Variant 1 for N16 so this should be correct. Pls note that this is chap Saw and if you order pls state your car's chassis code, manufacturer and model which should be Nissan Almera N16)
  • Damping Adjustable: No. Damping is fixed at factory.
  • Ride height adjustable: Yes, Independent Ride height adjustable: No so if you lower too much you will alter spring preload and damping.
  • Rebuildable: I should think so. There is no distributor listed for MY in KW's website. Only Singapore Indonesia and Thailand. Duh!
  • Front Spring Rate: Not known, Rear Spring Rate: Not known.
  • Top Mounts: Use back the stock rubber top mounts
  • Other Notable Features: TÜV certified. Available in two different damper body material - galvanised steel and "Inox" or stainless steel. Composite spring collar perch.
  • Price is not cheap at close to 1000 Euros (RM4.1K) for the Variant 1 Inox line not including shipping and tax. KW command a price premium over AP and Weitec due to their reputation and quality.
Thanks to Mike Kojima and the Dog III Time Attack race car we have the 3-way adjustable motorsport race coilover damper. These are high pressure nitrogen gas monotube configuration with separate remote reservoir. Front dampers are inverted with linear ball bearings to minimise friction. Aluminium is used for the damper bodies to minimise weight.
  • Part Number: Contact KW.
  • Damping Adjustable: Yes. 3-way adjustable for high and low speed compression damping and rebound damping.
  • Ride height adjustable: Yes, Independent Ride height adjustable: No. This is a professional motorsport coilover damper hence optimum ride heigh is customised to your specs.
  • Rebuildable: Definitely Yes.
  • Front Spring Rate: 700 in/lb (12.5 kg/mm) with helper spring on the Dog III, Rear Spring Rate: 900 in/lb (16 kg/mm) with helper spring on the Dog III. In reality KW can build the damper to your range of preferred spring rates.
  • Top Mounts: To your specifications. The Dog III uses Ground Control front spherical bearing top mounts adjustable for camber and caster. To install such top mounts you first have to chop off the front suspension turret/tower tops and reweld back metal plate allowing for the adjustment. Rears are non-adjustable spherical bearing and are "plug and play".
  • Other Notable Features: The dampers have a very short body resulting in a very low ride height (4 inches or 101.6mm lower than stock). This is a proper race car damper after all. Full technical details can be found in MotoIQ. I also have a write up for the Dog III's suspension. This is really serious stuff.
  • Price is equally serious @ > 24K RM for Dog 3 spec not including shipping and tax. Yes that's right. Twenty four thousand ringgit! Shocks at motorsport pro-level are all around these region or even significantly more once you progress to factory "works" level. Just ask how much WRC spec Reiger cost. So are you willing to pay?
Weitec
Weitec Fahrwertechnik offer the Hicon GT, GTN  and TX "Plus" coilover dampers but only the lower end Hicon GT twin tube coilover damper is available for the N16.
  • Part Number: 13285001
  • Damping Adjustable: No. Damping is fixed at factory.
  • Ride height adjustable: Yes. Weitec claim you can lower by as much as 30-55mm, Independent Ride height adjustable: No so if you lower too much you will alter spring preload and damping.
  • Rebuildable: Not stated
  • Front Spring Rate: Not known, Rear Spring Rate: Not known. Like AP, Weitec specs the coilovers according to vehicle weight which for the N16 is 1010kg front axle load and 970kg rear axle load.
  • Top Mounts: Use back the stock rubber top mounts
  • Other Notable Features: TÜV certified. Looks to be a conventional threaded galvanised steel body coilover damper with an aluminium spring collar perch. From the pictures on their website Weitec utilises helper springs for the Hicon GT. Also like AP, technical details are rather lacking from their catalogue and website.
  • Price is higher than AP coilover dampers at around 700 or so British Pounds or around RM3.5K not including shipping and tax. However looking at the specs and the lack of any local distributor/support I would recommend the Taiwanese or Japanese coilovers if you do track days rather than car shows.

6 comments:

Firdaus Asri said...

Bro,

Good comparo writet-up :)

Recently I'm in dilemma on which coilovers to opt based on my ciput affordability. Came across BC which is of good quality, specs similar to Tein Monoflex and cheap at 3.2k including top mounts. But unfortunately they don't have BR or V1 variant for my car. Striked that out. Then I've looked into these:

1. AP specifically APX - As you mentioned, it's the cheapest of the lot but based on reviews they're of crude built quality, twintube, mentally crashy ride and officially not serviceable in here.

2. Bilstein PSS9 - Superior built quality, inverted monotube dampers, ride height and damping adjustable, and of course tested in Nordschleife! Put it simply, the ultimate coilovers I can get for the Polo but it comes at hefty price of at least RM7k++ exclusive shipping and tax. Definitely my budget are not stretchable. Also officially not serviceable in here. :(

3. KW Variant 1 - Twintube, ride height adjustable but fixed damping from factory (~20% stiffer than stock). Good quality, priced within RM4-4.2k landed for V1. Overpriced when I can get H&R twintube coilovers for a lot less (below). Officially not serviceable in here.

4. KW Variant 2 - Older version of monotube coilovers (compared to Bilstein & H&R), ride height and basic damping adjustable. Price around 5k i guess. And officially not serviceable in here.

5. KW Variant 3 - Specs similar to Bilstein PSS9 and comes at about the same price as well. Definitely not.

6. H&R Twintube Coilovers - Good built quality, twintube dampers sourced from Bilstein and 30% stiffer fixed damping from factory. Price about 3.4k.

7. H&R Monotube Coilovers - Good built quality, inverted monotube dampers from Koni, 30% stiffer fixed damping from factory. Price around 4k.

8. H&R RSS Coilover - Not available for Polo.

In the end I've went for H&R monotube coilovers. Although they're not damping adjustable but for me, it's the most value for money without being too cheapskate hahaha...plus I can spend spare change to get it the ride height corrected plus corner weighting :)

Andrew Saw said...

Bro,

Honestly I would settle for something like the Bilstein PSS 9 or KW Variant 3s. You pay more but these are more effective in the long run especially if you do track days. From my experience it is going to be a big compromise having one damping rate for both daily driving and "enthusiastic" driving.

Firdaus Asri said...

True bro unfortunately my money tree doesn't grow fast enough hahaha

Andrew Saw said...

Same here Bro. That's why its BC Racing rather than Intrax 1K2 :)

Firdaus Asri said...

Yeah, if I can get BC, that would be it :)

Andrew Saw said...

Would have liked to try the double adjustable remote reservoir BC ERs but alas no application for the Slowtra.