Standard Shocks vs Sachs Performance package
 

Hi all,

Does anyone know how significant a difference the PP Sachs dampeners really make over standard? I believe they were offered starting 2017 as part of the available Performance Package on limited models. Are they a noticeable improvement over the standard or just a slight change?

Thanks!

IMHO they are too stiff for the street and not stiff enough for the track

Sent from my Pixel 3 using Tapatalk

I really enjoy them on the PP BRZ. I have a friend with a stock example, it is more crashy over bumps but nowhere near what a poorly sub-$1200 coilovers would be like. I think it's perfection for a street car that sees minor HPDE

People either love the Sachs or hate them. If you search these forums you'll see plenty of people who couldn't wait to swap out the Sachs dampers for coilovers. The common complaint being that they are crashy.

On the other end of the spectrum is that people have said the Sachs dampers are very comparable to the Bilstein B6. So yes they are firm and have good damping for stock suspension.

The Sachs are actually more compliant while offering better control.

They only get crashy when you pair them with lowering springs.

The Sachs in my 2017 felt crashy with the OEM spings.

The suspension was the second thing I swapped, tyres were the first.

The roads here are quite bumpy though.

As with everything, Opinions may vary

When you say "crashy" what do you mean exactly?

Newer models with softer springs are far from crashy. Still firm, sure, but at least the rear doesnt skate around on potholes etc like the 2013 models.

The sachs are good if you can find them for cheap. I wouldn't pay $200+ a shock for em though.

I have a 2013 FR-S which had standard shocks for some time.
Those definitely felt a bit overdamped and crashy.

I then switched to PP Sachs when one of my stock Showas started leaking at 65k miles.
My impression of the differences:
The Sachs have a bit more low speed compression, so initial turn in support is improved. The stock FR-S shocks like you would hit the rear bump stops with a higher shock velocity which I feel made the car more tail-happy. The Sachs mitigate this to some extent, also the bump stops are a different color and possibly have a different spring rate range.
The Sachs don't have a ride quality that I feel is leaps and bounds better than the FR-S. They both have a sensation of feeling overdamped, the Sachs maybe a little less so.
Neither is really what I'd call a track-ready shock/spring setup. On bumpy tracks and sticky tires(<=200tw), you will find the available travel is insufficient. On high-g corners with some bumps, the chassis will have some oscillations from that lack of travel. (Buttonwillow's Riverside comes to mind)

I've never felt that Subaru's suspension tech/tuning was great. Whether on my 06 STi, 11 WRX hatch or the newer WRX/STI, the suspension leaves a lot to be desired.

With that being said, I've been a long time BMW guy so that's my comparison. Not trying to sound like a BMW snob, but I think a lot can admit, manufactures have "chased" BMW for years....whether that's steering feel, suspension tuning, exterior styling, technology, etc, they've WERE the "benchmark" for many, many years (nowadays is different as they've seemed to lost their way).

The non PP suspension, IMO, is better on the street than the PP suspension. The PP suspension is over damped for most street applications (I live in NH). Yet, the PP suspension isn't great on track (very, very few stock suspensions are good on track).

Again, just my $0.02.

Sent from my Pixel 3 using Tapatalk

with lowering springs, you get a much harsher ride because the damping curves are specific to the oem springs. You typically get overdamped compression and underdamped rebound.

Yeah I can attest to this. Got lowering springs on Sachs. Don’t care for the ride at all. Wish I went with coilovers. Lesson learned.


Sent from my iPhone using Tapatalk

Which Springs did you go with?

When test-driving new BRZs back in 2017, I found the PP cars to have noticeably more high-speed compression damping and 7/10ths handling felt more go-kart-like vs. non-PP. The non-PP cars seemed to me to have a smoother ride but still handled great. I really don't think the PP Sachs dampers are "better", just different. At the time I preferred the PP dampers but now I think the harshness in highspeed damping isn't warranted and gets kinda old sometimes. Anyway, I went with the PP primarily for the brakes. I hate changing pads with sliding calipers...

A lot of "sport" suspensions at this level of car and beyond are more designed for a sporty feel than actual performance. They way they designed in the handling balance characteristics on these cars is another example. I do think the PP dampers are better on track and a solid improvement in every way over the early shocks for the twins. And definitely an upgrade if your original OEM shocks have 80k miles on them!

- Andrew

I don't see why you would go through the effort and cost of switching to PP dampers/springs when you could just get one of the affordable coilover setups out there.

I installed TRD springs on my car with the Sachs and i think that it rides and handles better than with the stock springs. It seems to absorb impact better with the TRD springs, while being flatter in corners.

Mike_ZN6: imho there might be good deals for used PP ones from someone parting out them exactly because upgrading to something else. So imho instead of choice between PP vs aftermarket coilovers, it's rather OE vs PP.

Stock has always been fairly overdamped in compression and rebound...gives it that "sporty feel" that ends up being crashy in certain instances and not always the best performance or ride.

Some lowering springs are actually a better match to stock shocks in terms of rebound % critically damped than stock springs. The problem is that most of springs lower too much and there's not enough travel, so it doesn't matter. RCE Yellow (duh), TRD, Eibach Prokit, and Swift are the only springs I would consider.

- Andrew

Sure coilovers have come a long way and "cheap" doesn't always mean bad. But not everyone wants to bother with the complexity of coilovers. And some people like myself need to keep the car OEM whether it's to maintain ride height for winter driving, or to stay in stock class at autocross.

Can you share some information on how the PP dampers match with the yellows vs OEM springs? Are they still slightly over damped with the Yellows?

Background:
1. "Critically damped" or a critical damping ratio of 1.0 means no "overshoot".
2. The "rule of thumb" damping ratio is 65% or 0.65 for sports/race cars for rebound. Some consider more than this to be "overdamped"....some consider more than critically damped (1.0) to be overdamped. For me, overdamped just means too much damping. :) Lots of factors could lead to more (or less) damping to be "ideal" for a given application and "ideal" will probably be different at each end of the car.
3. The ideal damping ratio also depends on piston speed. A relatively lower damping ratio for high piston speeds (bumps) is generally a good thing for some cars. A higher damping ratio for lower piston speeds (body roll) is generally a good thing for track cars. That's a digressive shock.

Since I have the #s handy....

With the 2013 shocks, the fronts are what most would call overdamped in rebound at both low and high speeds, with both stock and our RCE Yellows. Well over 1.0 in low speed (about 1.15 at 2 inches per second with RCE Yellows), and > 0.80 for high speed. The rears are between 0.60 and 0.70 for both low and high speed with our Yellows.

For PP shocks it's a little better, but not that different. I unfortunately do not have those #s handy. It certainly does not go below 0.60 up front.

- Andrew

That's helpful, thanks! My main worry about PP+Yellows was that the extra spring rate would overwhelm the shocks.

Not to thread jack, but it’s related. so do you go rce yellows/ Bilstein b6 or another lower spring with b6 for DD or go to coil overs. Have 50k on my stockers but will be thinking about it in a year or two with my mileage a year (15k a year)

IMO slightly spring rates (within reason) "overwhelming" shocks is a bit of a myth...

The fact is that critical damping varies with the *square root* of spring rate, not linearly. So a given damper will generally accommodate a fairly wide range of spring rates. If you were at, say 75% of critical damping with stock springs, you'll be at 66% critical damping with 30% stiffer springs.

I don't feel underdamped at all running Swift BRZ Sport springs with the stock PP dampers, and they're 34%F/43%R stiffer than stock. If anything still overdamped in terms of high-speed damping.

My bigger concern is the lack of bump travel with the stock dampers and running 30mm lower than stock...

Good question...our first BRZ shop car (owned by Myles) got a whole lot of goodies and was pretty track focused.We ran RCE Tarmac 2s, Ohlins (modified), JRZ, Bilstein, etc.

For our 2nd shop car....which is my personal car...we were targeting a more mild mostly DD build. My initial plan was Bilstein B6 with our RCE Yellows, which I'd spent plenty of time on. That changed because the Bilsteins were out of stock for like 2 years, and then we developed our RCE SS1 coilovers. So I helped develop those and run the final product on my car (and now it's turning into a rally-x car, but that's another story).

The advantage of the Bilstein B6 + RCE Yellow setup is that it's simple. Just put them on, get a good alignment, and go have fun. It rides and handles well, and you can focus on driving. One limitation is that it's not ideal with wide sticky tires. But with a 225 Michelin PS4s or similar, it's great. For roughly $1200, it's a great simple DD set up for a fun street car.

Coilovers can be better, but they're not always better. The damper itself is the most important part of the equation and most options under $1500 have valving that is not as good as a Bilstein B6. More features like height adjustability and camber plates etc., but the shock valving itself isn't always great. They may not have a lot of travel and the camber plates they use can be junk.

That said...there are a couple good coilover options under $1500 with impressive valving for the money. You'll usually get stiffer spring rates than RCE Yellows (which is good if you have stickier and/or wider tires), and sometimes more travel. The good ones at that price point (RCE SS1, CSG Flex, Bilstein B14) will ride at least as good as stock with much better handling. They'll still require a bit more effort to get set up just right, but shops like us will help you with that.

Beyond $1500, most coilovers will be more track focused, but can still be tuned to provide a good DD ride with the right set up.

Hope that helps. Happy to answer PMs too.

- Andrew

Not the guy who asked the question, but thank you. Very informative

Sent from my SM-G950U using Tapatalk

I echo above. Thank you very much.

FYI, I discovered that there are more types of Performance Package Sachs shocks, while just a type of springs.
Toyota used always the same shocks, that differ from Subaru. Subaru had 2 different shocks set, revised for models G and H (let's say from 2018).
Then there are the Toyota GR and Subaru STi, with specific springs, but this is another story...

That's actually very interesting. Do you have the specs for all the combinations for these?

I’m actually about to install Sach Dampers and STI pinks tomorrow. I was between rce yellows and STI pinks. Got a really good deal on very low mileage Sachs off a 2019 PP and STI pinks off a 2018 TS. Quick question, are the rear LCAs on the performance package different than the standard models? Or would I be able to just put these right in?

The rear LCA's are the same across the range as far as I'm aware. Also, the STI Pinks are not the same as the TS model springs, even though they are also pink. I have the TS springs and dampers also waiting to go on the car.

Thanks! Is there any information available on the TS STI pink springs? I’ve recently learned these are not your typical STI pinks. No intention of thread jacking and thank you all again. Timing of this thread couldn’t be any more perfect for me personally lol.

Are the Sachs monotube? I am aware that the standard shocks are a good compromise between performance and cost, but I am not sure about the ones from Sachs. Maybe a bit better than standard while keeping the cost relatively low?

I'll post later all the part numbers.

Nope, still twin tubes. Better for street, worse for track.

These are the part numbers for PP parts; beside of the P/N all PP springs are marked as 3 blue for front and 1 blue and 1 white for rear:

Toyota:
Front spring: SU003-07194
Rear spring: SU003-07196 (Models E-F, same as non PP)
Rear spring: SU003-08065 (Models G-H, same as non PP)

Front strut R: SU003-06790 (Marked 20310-CA140 on strut, red sticker)
Front strut L: SU003-06791 (Marked 20310-CA150 on strut, red sticker)
Rear shock: SU003-06796 (Marked 20365-CA130 on shock, red sticker)

Subaru:
Front spring MT: 20330CA200 (Same as non PP)
Front spring AT: 20330CA210 (Same as non PP)
Rear spring EU/US: 20380CA210 (Models E, F, G production date 20180101-20180930, same as non PP)
Rear spring EU/US: 20380CA211 (Models G-H from production date 20181001, same as non PP)
Rear spring JP: 20380CA200 (Models E, F, G production date 20180101-20180930, same as non PP)
Rear spring JP: 20380CA201 (Models G-H from production date 20181001, same as non PP)

Front strut R: 20310CA160 (Models E-F, blue sticker)
Front strut L: 20310CA170 (Models E-F, blue sticker)
Rear shock: 20365CA120 (Models E-F, blue sticker)

Front strut R: 20310CA280 (Models G-H, yellow sticker)
Front strut L: 20310CA290 (Models G-H, yellow sticker)
Rear shock: 20365CA240 (Models G-H, yellow sticker)

GR (10 mm lower):
Front spring: 48131-18060 (Made by Chuhatsu)
Rear spring : 48231-18030 (Made by Chuhatsu)

Front strut R: 48510-18040 (Yellow sticker)
Front strut L: 48520-18040 (Yellow sticker)
Rear shock: 48530-18050 (Yellow sticker)

STi/tS 2017+:
Front spring MT: 20330CA260 (Marked 1 light blue and 1 yellow)(Lowered 10 mm)
Front spring AT: 20330CA270 (Marked 1 light blue and 1 yellow)(Lowered 10 mm)
Rear spring US: 20380CA270 (Marked 1 purple and 1 yellow)
Rear spring JP: 20380CA260

Front strut R: 20310CA240 (Model F, green sticker)
Front strut L: 20310CA250 (Model F, green sticker)
Rear shock: 20365CA220 (Model F, green sticker)

Front strut R: 20310CA300 (Models G-H, purple sticker)
Front strut L: 20310CA310 (Models G-H, purple sticker)
Rear shock: 20365CA250 (Models G-H, purple sticker)


Update: reading a Japanese article, I discovered that Subaru added a couple of stabilyzing spoilers behind rear wheels, on the bumper in models G and H, and suspensions have been tuned accordingly. Toyota didn't, that's why Subaru rear shocks have been revised, but not Toyota's.


Update 2: not Sachs, but these are the other OEM specific options.

GRMN:
Front spring: 48131-18050
Rear spring : 48231-18020

Front strut R: 48510-18030
Front strut L: 48520-18030
Rear shock: 48530-18040


tS Model B (2013) (15 mm lower):
Front spring: ST20330AS010 (Marked 1 blue and 1 orange)
Rear spring : ST20380AS000 (Marked 1 white and 1 orange)

Front strut R: ST20310AS000
Front strut L: ST20310AS010
Rear shock: ST20365AS000


tS Model D (2015) (15 mm lower):
Front spring: ST20330AS030
Rear spring : ST20380AS000 (Marked 1 white and 1 orange)

Front strut R: ST20310AS070 (Made by Bilstein, inverted strut)
Front strut L: ST20310AS080 (Made by Bilstein, inverted strut)
Rear shock: ST20365AS030 (Made by Bilstein)


STi Aftermarket spring kit (15 mm lower):
Front spring: ST20330AS000 (Marked 1 white and 1 orange)
Rear spring : ST20380AS000 (Marked 1 white and 1 orange)(same of tS Model B/D)


STi Aftermarket shocks+spring kit (15 mm lower):
Front spring: ST20330AS010 (Marked 1 blue and 1 orange)(same of tS Model B)
Rear spring : ST20380AS020 (Marked 1 blue and 1 orange)

Front strut R: ST20310AS040 (Made by Bilstein, inverted strut)
Front strut L: ST20310AS050 (Made by Bilstein, inverted strut)
Rear shock: ST20365AS020 (Made by Bilstein)


86/BRZ Race coilover, STi and TRD are same kit (made by KYB):
TRD shocks kit MS260-18001 (Yellow color)
TRD springs kit MS250-18001

STi shocks kit 20300AS000 (Silver color)
STi springs kit 20300AS010


I missed the specific Toyota 86 14R60 coilover, as you can't order them, and not suitable for street, with square 14.6K springs!

This is wonderful, well done sir!
But I have to ask, what are the model letters? Different build date ranges?

Holy shit thanks for the info dump!!!


Sent from my iPhone using Tapatalk

Yes, in Japan they are identified as model number, let's say that model E Is built from April 2016, it's the first facelift.

And that just the Sachs dampers.. I wonder if the CA--- indicates the valving like how bilstein tags their shocks. There a different shock for every version of the sachs equipped cars it seems like.