Bilstein struts and shocks: Lengths and Valving

[foxclan Avid PP Poster! Find all posts View Profile Close foxclan]

Hey all,

For those who are interested in the top of the range monotube bypass adjustable Bilstein, this is even better than the 1478LT unicorn!!!



Best

Mark

"Pure Horn"

[Whitey Shockie Maker of the Month Award Find all posts View Profile Close Whitey]

Hey all,

I finally managed to dyno a new 2.8 diesel 150 Prado OEM strut, valving data shown below;



As you can see from the tables on the first page of the thread, the 150 specific Bilstein strut 24-173032 is valved 520N higher in rebound compared to the OEM strut at 0.52m/s.

The 24-173032 strut was matched to a 670lb/in coil by Quadrant during its development.

This explains why many 150 drivers complain of a "boaty" feeling driving the 150 on OEM suspension. The OEM 150 coil is a massive 780lb/in, so the OEM strut is not only under valved by ca. 500N, it is also very poorly matched in terms of coil rate, and will always struggle to control the OEM coil.

I have had feedback that the front end feels softer when moving from a 24-173032/586lb/in combination to a 24-173032/660lb/in, which can likely be attributed to the better matching of the 24-173032 valving to the higher rate coil.

This emphasises the importance of not only having the appropriate amount of valving, but matching that valving carefully with the coil rate.

For reference, the Quadrant 120 strut 24-238762 is matched to 620lb/in coils.

Best

Mark

[Wtrxprs007 Senior Member Find all posts View Profile Close Wtrxprs007]

Great thread guys!

Somebody once said that the bushes suffer prematurely if they are tightened without the weight of the car on the suspension?

Yes. You have to set the preload on them before torquing up to spec otherwise you'll be up for another bush soon

[Way2go Member Find all posts View Profile Close Way2go]

The lower bushes in my BE5-A712s really need replacing - any word on the 'new, improved' Superpro bush availability, or any recommendations from anyone as to a good replacement item (brand, part number, etc.)?

[craigm Addicted PP Member Find all posts View Profile Close craigm]

The lower bushes in my BE5-A712s really need replacing - any word on the 'new, improved' Superpro bush availability, or any recommendations from anyone as to a good replacement item (brand, part number, etc.)?

http://www.pradopoint.com/showthread.php?39401-Long-life-synthetic-composite-elastomer-bushes&p=555467&viewfull=1#post555467

[craigm Addicted PP Member Find all posts View Profile Close craigm]

Even better... there's a group buy that Whitey has gone to the trouble to arrange. http://www.pradopoint.com/showthread...l=1#post558042

[Way2go Member Find all posts View Profile Close Way2go]

Even better... there's a group buy that Whitey has gone to the trouble to arrange. http://www.pradopoint.com/showthread...l=1#post558042

Thanks Craig!

[Whitey Shockie Maker of the Month Award Find all posts View Profile Close Whitey]

Hey all,

Here's a plot of three of the commonly used front Bilstein struts showing how the valving can vary;



I didn't get a chance to dyno a 24-238762 before Quadrant closed, but it will be quite close to the 712 valving, slightly softer compression.

The behavior of the latest M2 modification of the BE5-D563 (which I am running on my Prado) is interesting. The bleed circuit in the piston head looks to be differently shaped on the rebound side, with the rebound stack opening up around 100mm/s higher than the 24-173032-1. I can easily feel the front end roll at low velocity, eg. cornering through roundabouts etc.

The 24-173032-1 also shows stronger compression Forces in the low-mid velocity range compared to the D563. This may translate to a slightly more bumpy on-road feeling.

Hope you are all enjoying your Bilsteins!

Best

Mark

[brock05 Junior Member Find all posts View Profile Close brock05]

Thanks for all your time and effort on this Mark, I'm more than happy with my setup provided by Zordo and it has provided all the attributes (on road) that i wanted over my old setup (haven't had a chance to play offroad yet). The information you have supplied here played a major role in my decision making process along with talking to John.

Cheers
Brad

[Whitey Shockie Maker of the Month Award Find all posts View Profile Close Whitey]

Hey Brad,

Hope you enjoy those Bilsteins!

Best

Mark

[bricat Junior Member Find all posts View Profile Close bricat]

Can you tell me how these super dooper by-pass remote canister shocks work when you are travelling along the Gibb River road or similar. It would not take long for the remote canister to reach the same operating temperature as the main body? Am I missing something here or should I say I am missing something here.

[Whitey Shockie Maker of the Month Award Find all posts View Profile Close Whitey]

Can you tell me how these super dooper by-pass remote canister shocks work when you are travelling along the Gibb River road or similar. It would not take long for the remote canister to reach the same operating temperature as the main body? Am I missing something here or should I say I am missing something here.

Hey Brian,

In most of the bypass shocks it's just a needle valve which throttles the oil flow rate allowing the valving to be adjusted over a specific range.

You are correct about the reservoir attaining the same temperature as the main shock body....it just means they take a bit longer to heat up compared to a shock with no reservoir.

The real benefit of having the reservoir is you have more surface area to allow the shock/reservoir system to cool (also allows a shorter closed length in the main shock body as gas chamber is transferred to reservoir). This means that the shock/reservoir system won't fade as quickly as a shock by itself. It will eventually fade though.

The same principal applies for larger 60mm piston shocks...they hold more oil, so they take longer to heat up, but they also have more surface area from which to dissipate thermal energy.

All shocks will fade eventually no matter their diameter or if they have a reservoir.

In saying that, monotubes will be far better in thermal management terms than twin tubes.

Some shock companies have done extensive dyno testing and have performed extensive cycling to see how quickly they heat up. I know Tough Dog have done dyno tests on a wide range of shocks, but it is highly unlikely you'll ever see that data!

Hope this helps you out!

Best

Mark

[brock05 Junior Member Find all posts View Profile Close brock05]

Hey Brad,

Hope you enjoy those Bilsteins!

Best

Mark

So far so good :mrgreen:

[Whitey Shockie Maker of the Month Award Find all posts View Profile Close Whitey]

Hey all,

I’ve finally tracked down all the different versions of the D563 strut, valving is shown below;



The BE5-E232 is the Hilux TRD spec strut, also known by the Toyota Tokico part number 48510-YWR01. Toyota have just slapped their Tokico sticker over the E232 sticker.

The main difference between the E232 and the original D563-M0 is the rebound is higher by around 840N and compression is softer by around 880N.

The D563-M2 appeared many years later after the M0 version, and you can see that within valving tolerance it uses the same rebound as the E232. I would say D563-M2, E232 and D563-Gen8 all use the same rebound shim stack. However, the D563-M2 still uses much higher compression than the E232.

The soft compression of around 1500N has also been adopted in the latest D563-Gen8 strut for the new 2.8 Hilux. Note that the open length of the D563-Gen8 strut is limited to 555mm, as the double wishbone geometry on the new Hilux is different to its predecessor.

While all of these struts are curiously regarded by Sydney Bilstein as Hilux spec struts, there is no reason they cannot be run in a Prado. As I have discussed in other threads, high rebound struts on the Prado when combined with around 660lb/in coils can dramatically enhance the off-road performance of the IFS. I myself am running the D563-M2 strut with a 675lb/in coil and it is brilliant in the rough stuff.

However, the soft compression valving of around 1500N is of particular interest. Will this enhance the off-road performance of a Prado even more?

Another clue in this valving jigsaw puzzle is the valving of Koni struts. The Prado specific 88-1712 has 3100N/1500N. The Hilux specific 88-1713 has 3500N/1500N. Both of these Koni struts fall in the same range of valving as the D563 struts above. The 88-1713 in particular looks to have almost the same valving as TRD spec. The purely hydraulic 88 and 90 series RAIDS have a hard earnt reputation in the roughest of corrugated conditions, so the soft 1500N compression may be an important factor.

My on and off-road driving impression of the D563-M2 is very positive. Off-road in heavily rutted conditions on Fraser with soft 16psi tyre pressures, the IFS cycles brilliantly. On-road with 40psi, I can feel the front being slightly skittish on crappy bumpy sections of Brisbane roads. Lowering tyre pressures is the equivalent of lowering the compression valving, so for 40-60km/h in the sand and rutted stuff with low tyre pressure I doubt you’ll feel the difference between 1500N and 2200N.

On corrugations at moderately high tyre pressures of at least 30psi, then I think you’ll definitely notice the difference between 1500N and 2200N of compression, and the lower compression (TRD/Koni spec) may be beneficial at moderate speeds.

Higher speed driving in whoops will require higher compression to cope with bump outs.

Hope you’re all enjoying your Bilsteins!

Best

Mark

[Whitey Shockie Maker of the Month Award Find all posts View Profile Close Whitey]

Hey all,

The plot below shows a comparison of all the "TRD" spec struts;



The average compression of these struts is around 1500N.

The CalOffroad 24-218528 strut has slightly softer rebound, but within typical tolerance of +/-300N at 0.52m/s, it is the same as the others. It may use a softer rebound preload shim to knee over at lower velocity.

All of these struts come at 555mm open length, so you'll need to get them lengthened to 570mm for maximum articulation on the Prado IFS.

The Gen8 Hilux strut is probably the easiest strut to get hold of if you're interested in running this lower compression type of valving.

Best

Mark