Modifying Bilstein Shocks

[Shankenstein]

I ran across a couple video serieses (produced recently), and wanted to share.

The first set is not really professional-grade... but it's the same guy who wrote the DIY for ClubLexus (mentioned before). He walks you through the tools and procedures needed to rebuild BC Racing shocks. This is with Bilstein guts.

It covers depressurization, removing clips, removing wiper, draining oil, cleaning, replacing piston bits (ring, shims, etc), and reassembling everything.

[ame="https://www.youtube.com/watch?v=1L6b_AY9hbc"]DIY BC Racing BR shock Revalve tutorial - PART 1(Bilstein Internals) - YouTube[/ame]

[ame="https://www.youtube.com/watch?v=gvBN_3jZJF0"]DIY BC Racing BR shock Revalve tutorial - PART 2 (Bilstein internals) - YouTube[/ame]

[ame="https://www.youtube.com/watch?v=d3CPXOJh_g4"]DIY BC Racing BR shock Revalve tutorial - PART 3 (Bilstein Internals) - YouTube[/ame]


[ame="https://www.youtube.com/watch?v=4BMXsyO-fgE"]DIY BC Racing BR shock Revalve tutorial - PART 4 (Bilstein Internals) - YouTube[/ame]

[ame="https://www.youtube.com/watch?v=mDukDHoMSJg"]DIY BC Racing BR shock Revalve tutorial - PART 5 (Bilstein internals upgrade) - YouTube[/ame]

Also, for those looking into disassembling inverted struts (like Bilstein), check out Shaikh (from Fat Cat Motorsports) on a set of Mini Cooper struts.

[ame="https://www.youtube.com/watch?v=1kWL9PGfcW8"]How Shocks Work - Access Bilstein strut internal bump stop (1/7), v2.28 - YouTube[/ame]

[ame="https://www.youtube.com/watch?v=NsO_a01Ob7E"]How Shocks Work - Access Bilstein strut internal bump stop (2/7), v2.29 - YouTube[/ame]

[ame="https://www.youtube.com/watch?v=RU-p0qTNVIY"]How Shocks Work - Access Bilstein strut internal bump stop (3/7), v2.30 - YouTube[/ame]

[ame="https://www.youtube.com/watch?v=bNGd4eBoKtk"]Bilstein PSS9 - How to disassemble the adjuster prior to rebuilding the strut (4/7) - YouTube[/ame]

[ame="https://www.youtube.com/watch?v=dZ8S2k_2gEo"]A look at the Bilstein PSS9 shaft assembly (5/7) - YouTube[/ame]

[ame="https://www.youtube.com/watch?v=mplcbsgJZvw"]Close-up of the Bilstein PSS9 damping adjuster mechanism (6/7) - YouTube[/ame]

[ame="https://www.youtube.com/watch?v=suZcbqmm88s"]How to re-assemble the Bilstein PSS9 monotube insert to strut housing (7/7) - YouTube[/ame]

[burdickjp]

Originally Posted by strat61caster

Link for the hats? I'm still on the hunt for a cheap easy solution for the rear top hats... Right now it's either Raceseng or custom spacer, Beatrush would be good but I'm not doing 60mm springs and it's just as expensive as the Raceseng.

I'm having trouble finding them again. I'd found them a while ago because I was looking for an upgrade path that eventually included spring testing.

Sent from my SM-G900M using Tapatalk

[Kostamojen]

As promised, feedback on my little project, converting the front springs of the B14's over to Linear springs...

Parts used -

KW take-off Upper Spring perches from Racecomp: http://www.racecompengineering.com/i...bled-sets.html

Swift Springs from FRsport: Z60-203-040 (60mm, 8" tall, 224lbs)

Pics:

Before -



After -




As you can see, the Swift springs are much smaller than the progressive springs. At first I thought I would need to raise the perch half an inch to compensate for the shorter springs, but that was NOT the case! Keep the spring perches where you have them at if you do this, just swap the springs and adjust if needed!

Impressions -

The main reason I did this was that with the B14's I've noticed since I've had them that they have a hesitation with initial turn in. IE the steering actually felt unresponsive to start with, and then after a split second finally responds. It actually made the car have less steering wheel feedback IMO.

The second reason was for the ride, which some people have said is "bumpy" with the B14's. I knew it couldn't be because of the Bilstein shocks, cause they are quality shocks themselves. It had to be the springs!

As soon as I pulled out of the driveway, I IMMEDIATELY noticed quicker steering response!!! The steering feel itself had improved quite a bit, there was NO MORE hesitation during initial turn in! I test drove the car around the block and indeed it has improved.

After that, I drove it on some roads I commute every day on and the ride has improved as well albeit not as noticeable. I test drove it on the freeway and also, the ride has improved. Driving in a straight line on the freeway actually feels better too.

Upon further test driving, the back end still likes to step out nicely which is what I really liked about the B14 setup (always very controllable). There is a little more initial understeer that I have to be cautious of because of the lack of give with the first flick of the wheel, but other than that I'm VERY happy with the results.

I don't plan on changing the rear springs anytime soon, but I could easily say that running a 325 or 350lbs spring would work well if you want to keep the rear end more planted. My primary concern is with a ride more capable of dealing with rough roads and daily driving than pure track driving.


P.S. I don't run camber plates up front, I run camber bolts plus crash bolts on the strut. I do run the Subaru Group-N tophats though.

[strat61caster]

Originally Posted by Kostamojen

The second reason was for the ride, which some people have said is "bumpy" with the B14's. I knew it couldn't be because of the Bilstein shocks, cause they are quality shocks themselves. It had to be the springs!

I'm starting to think that a big part of the ride quality is Bilstein's extremely conservative bump stops. Stock the 86 has ~3" of bump travel, numbers kind of swing all over the place but this thread is currently claiming 2.5"

http://www.ft86club.com/forums/showthread.php?t=26661

Bilstein uses their own bumpstop up front which iirc is ~60mm and reuses the stock rear which is ~50mm, so if you lower the car 1" off of 3" inches of travel and the bump stops are basically ~2" long... well the conclusion is that the B14/B16 pretty much sit on the bump stops at all times.

Can that design work effectively? Yes. Does it? I'm not so sure. I should have mine together beginning of next month.

I have a hunch your improved front end feel is partly due to it being less bumpstop active, but if you're car is super low than a stiffer spring won't change that. But it's pretty much spot on what I posted a few days ago to just get 60mm springs and top hat adapters and your total cost was probably ~$100 for each front end with the spring at ~$80 and the top hats from Racecomp at $25 each which is a pretty economical upgrade imo.

[burdickjp]

Originally Posted by Kostamojen

As promised, feedback on my little project, converting the front springs of the B14's over to Linear springs...

Parts used -

KW take-off Upper Spring perches from Racecomp: http://www.racecompengineering.com/i...bled-sets.html

Swift Springs from FRsport: Z60-203-040 (60mm, 8" tall, 224lbs)

Pics:

Before -



After -




As you can see, the Swift springs are much smaller than the progressive springs. At first I thought I would need to raise the perch half an inch to compensate for the shorter springs, but that was NOT the case! Keep the spring perches where you have them at if you do this, just swap the springs and adjust if needed!

Impressions -

The main reason I did this was that with the B14's I've noticed since I've had them that they have a hesitation with initial turn in. IE the steering actually felt unresponsive to start with, and then after a split second finally responds. It actually made the car have less steering wheel feedback IMO.

The second reason was for the ride, which some people have said is "bumpy" with the B14's. I knew it couldn't be because of the Bilstein shocks, cause they are quality shocks themselves. It had to be the springs!

As soon as I pulled out of the driveway, I IMMEDIATELY noticed quicker steering response!!! The steering feel itself had improved quite a bit, there was NO MORE hesitation during initial turn in! I test drove the car around the block and indeed it has improved.

After that, I drove it on some roads I commute every day on and the ride has improved as well albeit not as noticeable. I test drove it on the freeway and also, the ride has improved. Driving in a straight line on the freeway actually feels better too.

Upon further test driving, the back end still likes to step out nicely which is what I really liked about the B14 setup (always very controllable). There is a little more initial understeer that I have to be cautious of because of the lack of give with the first flick of the wheel, but other than that I'm VERY happy with the results.

I don't plan on changing the rear springs anytime soon, but I could easily say that running a 325 or 350lbs spring would work well if you want to keep the rear end more planted. My primary concern is with a ride more capable of dealing with rough roads and daily driving than pure track driving.


P.S. I don't run camber plates up front, I run camber bolts plus crash bolts on the strut. I do run the Subaru Group-N tophats though.

I'm curious what your alignment looked like.

Sent from my SM-G900M using Tapatalk

[getbent]

RCE has there been any update?

Originally Posted by Racecomp Engineering

If you guys are able to wait just a couple of weeks, we may have something interesting for you.

- Andrew

[Racecomp Engineering]

Originally Posted by getbent

RCE has there been any update?

I'll spill the beans a little bit. We will be releasing a custom valved Bilstein non-ajustable coilover soon with 400 lbs/in springs (linear) soon. Price is more than B14s but remember these are custom valved with custom linear springs. From our testing...AWESOME ride quality and performance that's great too. Good simple fun set up.

- Andrew

[JoeHK]

Originally Posted by Racecomp Engineering

I'll spill the beans a little bit. We will be releasing a custom valved Bilstein non-ajustable coilover soon with 400 lbs/in springs (linear) soon. Price is more than B14s but remember these are custom valved with custom linear springs. From our testing...AWESOME ride quality and performance that's great too. Good simple fun set up.



- Andrew

Sounds very promising but what about us (most of the guys in this thread probably) who already own a set of B14 of B16's
Would you recommend just switching the top spring perches and get some linear swift springs because i'm not about to sell my coilovers
I mean, i still need the linear springs so i guess best bet would be to get the spring perches from you guys and then find swift springs just like someone did a couple of posts above right?

I must say though your custom bilstein option sounds very interesting and if i didn't live across the pond and hadn't bought my coilovers yet i'd definitely be the first in line to buy them


Sent from my Potato using Tomato

[Racecomp Engineering]

Originally Posted by JoeHK

Sounds very promising but what about us (most of the guys in this thread probably) who already own a set of B14 of B16's
Would you recommend just switching the top spring perches and get some linear swift springs because i'm not about to sell my coilovers
I mean, i still need the linear springs so i guess best bet would be to get the spring perches from you guys and then find swift springs just like someone did a couple of posts above right?

I must say though your custom bilstein option sounds very interesting and if i didn't live across the pond and hadn't bought my coilovers yet i'd definitely be the first in line to buy them


Sent from my Potato using Tomato

We are working on putting together a spring and top perch package together for those that already have B14s. The rates would be a good bit softer than our custom coilovers since you'd be without the revalve but it should be a nice combo. It'll take a little more time.

- Andrew

[getbent]

Will these include top-hats?

Originally Posted by Racecomp Engineering

I'll spill the beans a little bit. We will be releasing a custom valved Bilstein non-ajustable coilover soon with 400 lbs/in springs (linear) soon. Price is more than B14s but remember these are custom valved with custom linear springs. From our testing...AWESOME ride quality and performance that's great too. Good simple fun set up.

- Andrew

[Racecomp Engineering]

Originally Posted by getbent

Will these include top-hats?

No, optional camber plates but you can use stock mounts.

- Andrew

[wootwoot]

What kind of tire would pair well with a 400lb spring? I'm on 225 MPSS at the moment.

[Shankenstein]

Originally Posted by wootwoot

What kind of tire would pair well with a 400lb spring? I'm on 225 MPSS at the moment.

It's good to analyze grip level vs effective wheel rate.

Dimensions: From stock, you're increasing the contact patch by 9% (7.5" to 8.2").

Compound: The compound is designed for more grip, and based on C/D's test (LINK to PDF), it's probably ~20% more grip.

You may see lateral forces ~30% more than stock, so a good set of lowering springs would be sufficient for your current setup.

For 400 lb/in springs, that's 3x stiffer up front and 2x stiffer in the rear (for a Toyota FR-S). They will be stiff, but dampers will determine if this is back-breaking or buttery smooth. Either way, your sway bars and bump stops will be less relevant (a good thing, in my opinion).

If this is a daily driver (with lots of potholes and hopping curbs)... this may not be ideal. For "street" tires (Direzza, RS3, RE71R, Rivals up to 245 width) with bolt-on power levels (200-250 hp), this is a fine choice. If you're pushing 300+ rwhp and R-compounds, you'll want more.

TL;DR - 400 lbs/in springs will be stiff... but it's OK with your current setup and will be future-proof for upgrades to tires and power. Once you transform into a track monster, a revalve and new springs are in order.

[AZP Installs]

Originally Posted by Racecomp Engineering

I'll spill the beans a little bit. We will be releasing a custom valved Bilstein non-ajustable coilover soon with 400 lbs/in springs (linear) soon. Price is more than B14s but remember these are custom valved with custom linear springs. From our testing...AWESOME ride quality and performance that's great too. Good simple fun set up.

- Andrew

Since you spilled the beans... these will be some very nice setups. Depending on which springs you opt for will determine if they will be motorsports or street bias.

We originally tried the B14s for Spec 86 Cup but they proved way way too soft for competition.

The RCE guys have come through with some nice units. If we can get on a track soon we will have even more feedback for them.

-Mike Paisan


Maintaining, Modifying and Educating TriState Enthusiasts since 2001.
Like us on Facebook! | E-mail: sales@azpinstalls.com | 725 Fairfield Ave | Kenilworth, NJ 07033 | 908.248.AZP1 (2971) |AIM: AZP Installs
"Race Tested, Enthusiast Approved!"