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Rexer200

Replacement for Ohlins R&T

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2 hours ago, AJ124 said:

I am about to go from Flex A to AST 5100. The tein's just don't cut it on a B road and a bit soft for track work. AST offer a raised front top mount which should be a helpful addition, I am assuming its the same top mount @Deacon has on his Moton's.

These ones?   https://www.vividracing.com/ast-suspension-front-top-mount-subaru-brz-20122018-p-152407840.html

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18 minutes ago, Deacon said:

That's what I have and AJ is getting yes

What are they like for B roads? How come only the fronts have raised top mounts? I thought the rear travel was more of an issue 

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Imho one needs to keep in mind that while rears are shorter and of short travel, but it's more of challenge for shock maker, as actual rear wheel travel is higher then shock's itself, due suspension ratio of 0.75 (as shock is attached not to rear wheel hub like front mcpherson struts, but to mid of LCA. That changes also effective springrate btw).

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5 hours ago, Church said:

Imho one needs to keep in mind that while rears are shorter and of short travel, but it's more of challenge for shock maker, as actual rear wheel travel is higher then shock's itself, due suspension ratio of 0.75 (as shock is attached not to rear wheel hub like front mcpherson struts, but to mid of LCA. That changes also effective springrate btw).

Where did you get 0.75 from? Is this GT86 or guestimate? The early Swave RCA I have offer 3 shock lower mounting points

What I wanted to know is if the guys with Motons /AST have fitted rear raised top mounts or flat ones?

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1 hour ago, Rexer200 said:

What I wanted to know is if the guys with Motons /AST have fitted rear raised top mounts or flat ones?

Moton / AST don't make rear raised top mounts.

Church is correct about the motion ratio - the front is approximately 1 and the rear approximately 0.75 so a 4/5kg spring set up is actually approximately 4/3.75kg at the wheels.

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43 minutes ago, Deacon said:

Moton / AST don't make rear raised top mounts.

Church is correct about the motion ratio - the front is approximately 1 and the rear approximately 0.75 so a 4/5kg spring set up is actually approximately 4/3.75kg at the wheels.

Coming back to the point of this thread what I was looking for is peoples real world experience on UK B roads and track which is why I signed up to the UK GT86 forum in the first place.

I know the suspension theory I know the 0.75 is some approximation or guesstimate on the rear ratio however how does it help me? There are masses of suspension theory and technical threads all over the Internet but positive recommendations from other owners on their current set up is what I was looking for.

if anyone else has some valuable real world GT86 experience with their suspension I would be very interested to hear it?

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So to summarise the real world experiences from this so far;

* The original Ohlins kit with 6k springs and top mounts is good for B roads / Track
* The Flex A's are good on B roads but ultimately too soft for track
* Moton's are excellent on B roads and track but very low speed bumps not so good (adjustment on the Moton's is greater than AST5100's)
* At least one person has AST5100 but not sure of their opinion of them

 

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@Rexer200 I think there are two big problems with getting opinions from others on something like suspension. Firstly most people have only owned one set up and will say it's the best but don't have a comparison and most people don't want to say that what they've spent their hard earned money on isn't as good as something else. Secondly suspension seems to be one of those things that's very personal in terms of preference. E.g. I like very little roll in my car and lots of grip so the set up I have with the Motons and bigger ARB's etc suits me but someone else might not like it at all.

In terms of gathering opinions I think they'll always be somewhat biased but can be useful for highlighting issues people have had which may steer you away from a certain set up for instance - like maybe issues with longevity or rust or something.

 

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@Deacon I agree with you. Which is why my main focus was a bumpy UK B road at speed. Here more than anywhere the driver preference is taken out of the equation. If the car is hitting the bump-stops and being thrown all over the place or feels unstable then most drivers, regardless of ability will know about it.

Amber Performance have offered me their GT86 with Flex A's and EDFC Pro so I'm going to try to get over there and take that out

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@Rexer200 I went with them as they are fully customisable in regards to valving and spring rates. I can tailor them further if needed, much like Deacon has done with his Moton's. The raised top mounts were a big factor as it regains 30mm of travel. I can't give any feedback until I fit them, get a geo set up and put some miles on them on roads I know well, then I can offer comparison to the flex A's. 

The flex A's for the money are good, but if you have more budget there's defiantly better options. I have been a passenger in Ade's Ohlins equipped car on track and it was far more controlled than my Tein set up, we were both running the same tyres at the time, so that eliminated one variable. I was put off Ohlins by some recent QC issues a few member on the other forum had with newer kits, not sure if they have been resolved.

On my B road 7 mile journey to work there is at least 6 points my car hits the bump stops up front travelling at 60mph, I am only running 15mm lower than stock.

 

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1 hour ago, Rexer200 said:

@Deacon I agree with you. Which is why my main focus was a bumpy UK B road at speed. Here more than anywhere the driver preference is taken out of the equation. If the car is hitting the bump-stops and being thrown all over the place or feels unstable then most drivers, regardless of ability will know about it.

Amber Performance have offered me their GT86 with Flex A's and EDFC Pro so I'm going to try to get over there and take that out

That sounds like a good plan.

If you like the Flex A's but want firmer valving you could always order a set of the CSG spec Flex A's from the states to combine with the EDFC set up.

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5 hours ago, Rexer200 said:

Where did you get 0.75 from? Is this GT86 or guestimate? The early Swave RCA I have offer 3 shock lower mounting points

What I wanted to know is if the guys with Motons /AST have fitted rear raised top mounts or flat ones?

Well, it may differ where there are several mountpoints, but i guess not revolutionary, proportional to lever (wheel vs strut from LCA pivot axle) change if coilover mounts closer or further to wheel (as different lever - for same force pushed at wheel, different force on shock/spring), as alternative mount holes are close enough.
I have to double check though how real spring rate should be calculated from that motion ratio. Found eg. that motion ratio needs to be squared to get wheel rate from spring rate.

You can google on 0.75 motion ratio site:ft86club.com. Was mentioned in several suspension related threads.

EDIT    ok, this seems reputable enough source, as RCE is one of knowledgeable & well spoken of suspension vendors for twins. so indeed:

"To get the "wheel" rate of the spring, or the spring rate at the wheel, you multiply the spring rate by the square of the motion ratio.  So that 7k/5k is really more like 7 kg/mm front and 2.8125 kg/mm rear."

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@Church My Swave rear LCA's have a length of 44cm with lower shock mounting points at 30, 32 or 34 cm, meaning ratio is either 68%, 72% or 77%. 

At the moment they're fitted (as per Fensport) to the 34cm setting, meaning that for my current 3k rear springs it is effectively 1.77k at the wheel.
If I move the shock to the 30cm mounting point then the wheel rate becomes 1.38k ... not gonna do that!

When I fit the new 5k springs, choosing the 30cm mount would give me 2.31k at the wheel and the 34cm mount 2.96, so the 30cm mount maybe a good starting point for me.

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@AJ124 Thanks for the feedback...

* The original Ohlins kit with 6k springs and top mounts is good for B roads / Track
* The Flex A's are good on B roads but ultimately too soft for track (CGS spec stiffer but no UK review)
* Moton's are excellent on B roads and track but very low speed bumps not so good (adjustment on the Moton's is greater than AST5100's)
* AST5100,  Personalise with valving / springs, AST 30mm raised front top mounts (top mounts can also be fitted to other coilovers). no on road review yet
* Reiger R3, UK dealer will contact me next week, Used by Toyota for tarmac and gravel comp. cars but no UK road review
* Nitron NTR R1/R3 I'd love to hear from anyone in the UK who has these on an 86

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While CSG spec Flex A or SRC or RCE Tarmac and clubsport ones (KW/ST based) sound promising (and i also extend that with 949 racing Xidas shocks (many from US miata track crowd swear by those, so might turn out very competitive too) .. there is big BUT. shipping/import costs & non-locality for warrantying & servicing. For example, even if KW (in Germany) made by RCE valving spec theirs .. to service them you need them to ship back to RCE@US, then they will send to KW, then back, then to you .. non-locality imho is important enough bit, unless one by large gives up potential warrantying with extra shipping cost and waiting times and will use them for whatever wear resource they have till they last. I suspect non-locality issues also with australian suspension vendors products, unless they have local dealerships in UK.

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I had the Ohlins MP20 on my previous 2014 GT86 with the 30/40 springs, and have the MP21 on my current 2016 GT86 with the 50/50 springs and the Ohlins (solid) top mounts.

My experience with the 30/40 spring was similar to yours, and lost the rear at the track a couple of times quite unexpectedly because of not enough travel at the back. Luckly I recovered both times. The car was lowered to Ohlins recommendations, about 20mm in front and 15mm back.

With the 50/50 springs and 2' of camber at the back I have a quite a hard time getting the rear loose, and I also feel it long before it happens. But I also did not lower the car, I kept it stock height.

If I were in your shoes I would give the 50/50 springs a try.  

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@Adi Thanks for the feedback, really interesting to hear your thoughts about the Ohlins and the 5k springs. Hopefully I will be able to fit the 5K springs to the back of mine soon to see what it’s like. I would almost consider a stock setup like BRZ tS however my car has 300bhp via a Cosworth supercharger and 360mm AP 6-pots up front so not sure the stock suspension would cut it for acceleration and braking.


The one thing I’m not 100% sure of is that my rear socks from the MP20 kit have SUS6P2016L stamped on them and the manual for the MP21 kit only quotes the first part, SUS6P, however I’m not sure if the shock valving is different. 
I would’ve thought it should be since the 5k setup should require more rebound damping and less bump damping vs the 3k damper. 
 

Does anyone know for sure if Ohlins revised the rear damper valving MP20 to MP21?

184AB98F-9B96-4FFB-B0B4-EF7733C5D1CD.jpeg

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Well, imho good adjustable shocks should be able to accommodate +/-30% spring rate change.

As for MP20/MP21, IIRC they are essentially same, just that MP21 is German TUV approved and has rubber spring seats. So if there are any damping changes, then imho they might be vs earlier, MI20 shocks with stock 60/60Nm springs and included Ohlins camberplates in set.

Hmm, that sticker .. i wonder if it's for shock itself, or just for that "cup" with threads for height adjustment and mounting hole to suspension arm .. if later, it might be from generic Ohlins parts-bin and to be in many kits (eg. for some other Subaru cars), and not linked what valving in shock "core" with shims used is.

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I've been considering the MP21s when I get back to the UK with the Raceseng rear top mounts and potentially running stock front top mounts... 

 

Is anyone running the extended rear top mounts with Ohlins on here? Could that potentially cure the lack of damper travel? 

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@Addymk2 when I fit the 5k springs I should be able to tell you if the Raceeng top mounts will work, depending on if you have rear LCAs with lowered shock mounting points.

At the moment my car sits at 350 mm (center of wheel to arch) and with the 3k rear springs I’m not sure if it could sit it much higher. It looks like the height adjuster on the Ohlins damper is on its highest setting and the low ride height is caused by the sag of the soft springs and the 15mm lowered shock mounting point on the RCA. I could potentially add more spring preload but I don’t want to risk the spring going coil bound.

The 5k springs will sag less so will help raise the ride height,  I actually want to run the recommended 365mm height. 
I’ll let you know

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1 hour ago, Addymk2 said:

Is anyone running the extended rear top mounts with Ohlins on here? Could that potentially cure the lack of damper travel? 

Unless you run out of height adjuster on the Ohlins then the Raceeng extended rear top mounts won’t help shock travel. They are developed for non height adjustable shocks on shorter springs or for single height adjustable shocks like Bilstein, ie no separate height adjuster  

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10 hours ago, Rexer200 said:

Unless you run out of height adjuster on the Ohlins then the Raceeng extended rear top mounts won’t help shock travel. They are developed for non height adjustable shocks on shorter springs or for single height adjustable shocks like Bilstein, ie no separate height adjuster  

https://jdmuscleusa.com/collections/2013-brz-86/products/raceseng-13-brz-13-16-fr-s-shock-top-2in-rear-top-mounts-ohlins-road-track-only?variant=31185767235686

Interesting, they've developed a kit specifically for the Ohlins. I assumed it could potentially add to the dampers total travel, as opposed to going straight to the bump stops but I was wrong 🤦‍♂️

 

Thanks for the info mate.

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Worth understanding that these mounts don't magically increase travel. They allow to retain travel when you overlower car by relocating upper mountpoint higher when otherwise one would need to lower car that much at expense of travel.

If one doesn't lower to unwise amounts (possibly running into other issues, such as increased CV joint wear and fscked up geometry, and doesn't also get things like diff riser kit & roll center adjustment kits), but keeps it within range of adjustment of separate height adjustment, then such mounts serve no other function but that of emptying wallet.

"2 inches of extra rear shock travel"? When reasonable lowering for twins is usually mentioned to keep within 1inch?

As for ground-scraping slammers for looks .. i doubt they need any good shocks at all. I highly doubt good handling of car and coilover quality/performance is in any priority to them, so why pay extra for Ohlins + accompanying extra lowering hardware in such case.

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I just wanted to update this topic. I’ve now changed to the 50 N mm Ohlins Springs on the rear of my car and the ride has been transformed versus the old 30 N mm springs supplies with the SUSMP20 kit.

it’s just so much better without any bottoming on the rear I’m going to stick with this suspension for now. Fensport noticed a slight leak on the front nearside shock so I’m getting that rebuilt soon and at the same time I’ll fit 50 springs to the front, to replace the 40s and the front adjustable top mounts.

So affectively my kit will be upgraded to an SUSMP21.

still seems crazy why Ohlins would fit 30 springs to the rear in the first place especially considering the lack of travel versus the stock set up

 

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