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PostPosted: Tue Apr 19, 2016 10:08 pm 
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Space reserved for future info.

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PostPosted: Tue Apr 19, 2016 10:57 pm 
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I have spent a while researching options and specs of the various suspension options for the ST185. Through this I have gathered a fair bit of info on spring rates and damping rates adopted by many. I will update the first post in due course but options are very limited now unless you go custom.

Unfortunately most are now discontinued (although I seem to have been able to order most of them and just received a long wait).

Discontinued List :-
Eibach lowering Springs
Tein HA coilovers
Tein Superstreet Coilovers
Koni 8641-1211 SPORT rebound adjustable strut insert (damper)
TRD Springs - various
KYB AGX adjustable struts
....... you can see the pattern.

Items still in manufacture
1) Toyota standard struts
2) Bilstein front strut insert (Inverted mono tube) Part No. P30-0352
(Note P = Insert & 30 indicates valve diameter) These are not 36mm or 46mm Heavy duty types as some sites suggest and most of the benefit of the mono tube is lost (lower unsprung mass and able to use a larger diameter valve to provide better sensitivity at high velocity - more plush ride quality whilst still firm) they basically have an inverted damper within a bottom strut casing that all fits inside the standard Toyota strut casing!
3) BC Racing coilover.
Having spoken to them and looked at the shock dynos I have reservations. They are reported as being quite compliant and suited for road use. The shock dyno suggests they run little bump but plenty of rebound damping. There has been some reluctance to offer lower spring rates (only 1-2KG lower than they offer) and an indication that if they did that the warranty would be void.

4) Bespoke suspension = ££££

Performance options are therefore quite limited and easy/quick UK rebuilds/spares may not continue for much longer for any of them??

Bilstein will offer a UK rebuild/repair/revalve on their offerings and BC do offer replacement inserts shipped from Taiwan but having been bitten by Tein and their rebuild options I am more inclined to work with a UK supplier that will hopefully be around for a long time. This has led me to research the options a bit more and consider some possibly stupid ideas.......

A) Bilstein Universal Motorsport Strut 46mm of valve! $500 each : - http://www.bilsteinus.com/products/moto ... rts-strut/
Unfortunately not available in the UK and USA only :-(

B) Look at building up a Group 4 escort type strut casing from this http://www.motorsport-tools.com/coilove ... mm-id.html Laser cut some strut ears for the GT4 and weld them on. Use one of the various options of 36mm inverted Bilstein inserts from Grp4 escort, Pug 205 etc etc that can be easily & cheaply rebuilt & revalved (£70-£120 a corner it seems) and reliably sourced in UK from Bilstein or AVO. See:- http://www.motorsport-tools.com/escort- ... capri.html Note:- the 300/70 damping is pretty close to the GT4 Specific insert they offer (ideally it could do with a bit more bump and I have yet to ascertain if they are linear or digressive valved on the escort rally insert). The Pug 205 rally insert seems a better fit (maybe as the unsprung mass is closer with it having a proper front hub and driveshaft etc.)

I believe the escorts seemed to use 200-450 lb springs so circa 4KG to 8 or 9KG/mm so not far off sensible GT4 rates for road use.

Has anyone used the Group 4 type Bilstein inserts in their rally days? Any comment if they are durable/sensible for the basis of a custom setup?

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PostPosted: Wed Apr 20, 2016 2:53 am 
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On note of available suspensions:
• I have seen Ohlins for the 185 for sale. I am unaware of what shop makes them. My understanding is it is not officially from Ohlin, but I have no data.
• There is a suspension builder in the North Western USA who builds rally suspension for the 185. It costs about $2500. It is non adjustable. He has a huge ego, and says he leaves off adjusters because people will just mess up his work.
• Feal makes any of their trims for the 185. I use the 441, but they have a rally spec as well. All built to spec.
• The koni 8611 (race strut) should fit the oem housing, but may require a spacer due to length and a custom gland nut.
• Fortune Auto makes a set for the st205, that I think can be adapted to the 185. The rears bolt on, and the front just needs a lower threaded mount for connecting to the spindle. It already comes with a blank tube intended to weld to super strut. They also build to spec.
• BC offers a huge range of custom stuff, and will build a full 3-way external revision to spec, but it is costly. I think they quoted me $2800 for the setup I considered. If you order custom they will dyno plot each strut, which is more likely to ensure they are properly matched. Ordering off the shelf setup is likely not.
• KW will make a set for the 185 starting at $4500.
• You can buy TTE struts here: http://www.weverssport.com/rallysport/? ... p-n-450200
Will be very expensive if it is like anything else that was quoted to me and will need custom bits to work off a stock based 185.
• I have seen the Bilstein rally shocks go on sale quite a few times. They were not selling well, and I had seen them under $300 in the past. Of course money is still needed for valving, machining and welding.
• Ceika makes a full setup for the 185. The owner used to own a 165. They are slow and hard to deal with from the US, but likely easier from your side of the pond.
• Another option is to locate 4 front Evo MR struts and get those valved and adapted. I have seen a few cars do that, and out of the box they are pretty good struts.

It has been a while since I had been researching all this, but there may be a few other options out there I am not thinking of. I have owned the Tein HA, and they didn't suit my driving style. Very stiff, but tein would customize them for a price. I like my Feals so far in the few races I have done on them.

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PostPosted: Wed Apr 20, 2016 12:11 pm 
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Interesting thoughts.
If it wasn't for the issues getting the Bilstein Universal struts to the UK I would have probably gone for them. They are on sale at present at a couple of shops for $370 ish. I can't see anyway you are going to get Bilstein 46/50 setup for 3 times the cost as they only seem available in full race applications form bespoke coilover manufacturers.

The Koni Race series I had considered, would have to be the 8611 series as double adjustable and the single adjustable have far too much bump damping as designed for very high spring rates it seems. It is the the default option but some aspects put me off: -
1) Price at £330 per insert for the double adjustables.
2) you lose some of the digressive nature at low damping settings (as you seem to with all adjustables which is why I don't actually have a preference for non-adjustables strangely and contrary to most peoples desire).
3) rebuild/revalve doesn't seem easy and may not be possible which questions the longevity of the solution (will I have the same issue trying to source a new setup in 5 years time??).

The Evo option is interesting primarily as I believe the the EVO Bilstein B6 HD is a very similar arrangement to the off-the shelf ST185 B6 insert and I believe they use the same size (smallish for Bilstein) valve within a tube within a tube within the strut case. The good reviews may suggest I am being too fussy. Modding the Evo strut is possible but the ears are totally wrong so not easy.

EVO Specs
B6/B8

FRONT Part No. 35-118435
Free Length: 19.35/18.7 (inches!) (492mm/475mm)
Compressed Length: 13.35/13.39 (inches!) (339mm/340mm)
Compression Valving: 58/60 (Newtons*10 @ 52cm/sec or 20.5 in/sec)
Rebound Valving: 150/126 (Newtons*10 @ 52cm/sec or 20.5 in/sec)


Rear
Free Length: 21.73/21.14
Compressed Length: 15.96/15.96
Compression Valving: 96/96
Rebound Valving: 147/147

ST185 Specs
Bilstein B6 St185 Front
Part Number 34-003527 ( Old Bilstein Part Number= P30-0352) P=insert 30 = 30mm valve.
Free Length: 501mm
Compressed Length: 356mm
Compression Valving: 63
Rebound Valving: 260

Presumably the higher rebound to cope with the extra weight or the lardy GT4 front and/or higher spring rates required.

I havent looked at many of your other options yet.

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PostPosted: Wed Apr 20, 2016 4:01 pm 
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And just for reference data, here is a drawing of the Fortune 500 st205 setup. The simplest option would be to find a threaded lower mount from another coilover manufacture, but no one that makes them for the 185 has the same diameter and thread pitch for the tube size. Since the lower section is weldable you can get the tabs put on for mounting. They likely would not support knowledge of this setup, so for rebuilds you would just never mention the modification. They are digressive like the feals. The feals had more droop through, and only came with swift springs where on fortune it was an option. The better advantage of fortune is as your budget and experience with the car grows you can keep upgrading them. You can end up with external cartridge 3 way adjustable by the time you are done. The lack of support is why I ultimately did not go with Fortune. They are very stingy about who they will produce for, and if they discontinue a product, they will never offer it again.
http://s31.postimg.org/vri15djvf/ST205.png

On note of the EVO inserts, they are not HD, but HD is available. Evolution forums had some threads comparing them. The Koni 8611 is a great series. I almost went this option, but Koni wants to do all the rebuilding, and did not want to give me any of the information I wanted. You essentially need to know what kind of valving you want and have them meet those specs.

I think I found the dimensions of the tubes to be the same for the 185 and 205. So that may open more insert options. It is possible the bottom of 205 inserts have an extension though that might require modification to the 185 housing. Its been a couple years since I really spent time on this project.

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PostPosted: Wed Apr 20, 2016 8:39 pm 
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Hmm,
I've looked at the forums and I can see/find no B6 Sport all are deatiled as being the HD. I'd be interested if you can remeber where you found the comparison.

I've found plenty on Evo MR Bilstein vs B6 HD.

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PostPosted: Wed Apr 20, 2016 9:08 pm 
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I should have been more clear, but I meant the EVO mr struts and the B6 HD are not the same.
Just a quick search and one here notes in their development they are very similar, but not the same on the dyno.
http://www.evolutionm.net/forums/evo-ti ... st10865569

A little mention of it here too:
http://www.evolutionm.net/forums/evo-ti ... -hd-s.html

New MR shocks are more expensive than the B6 HD, but you can find used MR shocks cheap. I was looking at the used option since they need to be rebuilt for use in the 185 anyway.
The forum I linked is where I did much of my research. There is also a nissan road racing forum, which is where I got the idea of using the evo shock. I wasted months digging around in there, so there is no telling how deep that information is. http://nissanroadracing.com/showthread.php?t=3851

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