Bilstein Struts

[KenshinX]

I'm not really sure how old these struts are or the specs on them They were on the car when I bought it. After getting my L28et swapped in and running good on stock components Ive decided to work on the suspension. Well last week hastened the process. I notice that the wheel was sitting at negative camber with the top wheel pointing in the fender and i figured it was the tie rod or wheel bearing. After close inspection it seemed the strut/coilover was at fault. (fine cause I wanted to get new GC coilover kit anyway) Well after more inspection it seems the top threaded part of the strut snapped or the top plate piece connected to the camper plate gave way not really sure I just know the whole assembly was leaning against the inner frame. Well after getting the strut out I found them to be Bilsteins I was expecting them to be KYB or Tokico. The number on the sticker is P30-061 with 3060061H003 stamped at the lower half of the strut tube.

 

My question is since I dont know what the PO put together on this car. How can I tell if these are able to handle the coilovers on the car and if the failed because the spring rates were too much? Are these stock rated? I cant really tell what the spring rates are or who the springs are made by because I see no stamp I just know they are black and look to be in good shape. Any help would be appreciated. If possible and these are good struts I would like to get another set if anyone could tell me where I could get them from they measure about 14.750" inches at the tube

Edited December 25, 2010 by KenshinX

[JMortensen]

Someone made their own strut top, and that explains the camber too. The Bilstein strut insert is not the source of the camber. What you have there is actually pretty good. Looks like the PO wanted more neg camber and did what he needed to do to get it. It's a lot like Tom Holt's rear strut setup:

 

http://sth2.com/Z-car/shocks.htm

[KenshinX]

Well if thats the case I'm gonna try giving Bilstein a call and maybe I can order a new pair using the stamped number. The one picture the threads are snapped therefore I cant bolt back down on the camber plate. Thanks for the info and Link

[JMortensen]

Looks like a 5/8" monoball in the top, You might need a bushing in there to center the strut in the monoball.

 

If you're going to replace all 4, you can buy the Bilsteins mentioned in the strut thread here: http://forums.hybridz.org/index.php/topic/50944-the-strut-thread-koni-illumina-tokico-carrera-bilstein-ground-control/ and then you can buy the bushings to center the strut from Ground Control. With those current Bilsteins you will probably need a spacer underneath the strut. I used some 1.5 x .090 tube, which you can get from www.online-metals.com

[mark]

Ive seen a few Z cars trying to run a lot of castor that would snap off a strut top like that. Check and make sure that the part the strut top bolts to is a mono ball. I'm betting the mount that the strut bolts to does not move either by design or because it is seized up.

 

There is a reason the strut top snapped off. Try to find it before you put it all back together.

 

The other cause of broken strut tops is impact guns. Unfortunatly I know this from personal experience.

Edited December 25, 2010 by mark

[JMortensen]

Mark is right, my bad. I didn't click on the photos to make sure there was a monoball in there, I just assumed it was there. After clicking, I don't see one at all. That would be a real problem. Might take those aluminum pieces off and see what is under there. If the stock strut tower is all hacked up, you might be looking at a set of camber plates to fix it.

[260DET]

As well as a monoball there it should have a thrust bearing for the vertical load which should not be carried by the monoball. Some cheap aftermarket strut tops don't have that, see an OE setup as to how it goes together.

[KenshinX]

Great points guys. Ive actually been skimming through several threads and manuals to try to find what exactly I missing after taking down the whole assembly. I did not see any type of bushing or bump stop I guess you would call it anywhere when i removed the assembly. Is there anyone that can post a pic or diagram of what this set up should look like. I am actually having a hell of a time getting the camber plates off as you can see from the pics the bolts are so close to the hole mount that I can't get a socket or wrench around it to unbolt the top nuts or vice versa.

 

I was considering inexpensive plates such as these:

 

http://www.thezstore.com/page/TZS/PROD/PSDC15/23-4188

 

Jon: Thats actually exactly what I was trying to see by trying removing the camber plate.

 

Also is there any benefit to running the struts linked in the thread over the ones I have now? The car will likely not see any track or auto X and mainly be street driven, but not daily.

 

Bilstein P30-0032 revalved 300/100 in a shortened strut housing with some P/N 450424 gland nuts to adapt them to a Z strut thread.

I have Bilstein P30-061

Edited December 26, 2010 by KenshinX

[KenshinX]

As well as a monoball there it should have a thrust bearing for the vertical load which should not be carried by the monoball. Some cheap aftermarket strut tops don't have that, see an OE setup as to how it goes together.

 

 

Is this what you were referring to as the thrust bearing?

 

http://www.thezstore.com/page/TZS/PROD/23-4376

 

Although, I know I'm not running a the stock strut mount insulators. I also noticed that there was no bump stop on the strut so would a stock "bumper rubber" as the manual calls it be suffice?

 

The only camber biscuit style plates without going into all the mods to get it to work would be the MSA style ones I linked above but they have no monoball and I cant find any detailed reviews on them as to how they perform. I have found these and the price seems excellent are there any word on these plates? http://designproductsracing.com/Z_Suspension1.html

 

I may just go with a set of Illuminas since they measure out to a little over 14" in the front just as my sectioned tubes are and will probably be easier to find and easier to install with mods.

Edited December 27, 2010 by KenshinX

[JMortensen]

Bilsteins have an internal bumpstop, so nothing needed there. If you replace them all because of the damage, I wouldn't revalve the struts if it's a street car. Just get that part number and install them as is.

 

I am not a fan of the poly camber plates from MSA. Poly is very stiff, so the risk is that the same thing that happened to the current struts would happen with the poly in there. It just doesn't give enough. With a monoball in there the strut can swing back and forth with virtually no resistance. That's what you want.

 

I don't think you "need" the thrust bearing either. It is a good idea when you use a 5/8" monoball, but if you used a 3/4" monoball in the top, I think you could get away without it. The problem with the thrust bearing is that in order for it to work you have to put a weird side load on the spring, unless you use the new Ground Control camber plates. By putting the load right on the monoball you alleviate that side loading of the spring, but I don't know anyone that makes a 3/4" monoball camber plate for a Z.

[KenshinX]

Thanks for the advice again Jon, The "design products racing" camber plates have an option of a 5/8 spherical bearing and a 3/4 diameter bearing, so I guess thats my answer right there. I may give them a call and figure out whats, What I'll be sure to post pics hopefully I dont run into anymore issues during the re-install.

 

Design Products Racing:

 

http://designproduct...uspension1.html

[johnc]

Bilstein charges $65 per shock to disassemble and inspect. New shock shafts are $10. I suggest you pull all 4 shocks and send them off to be inspected. Call 858-386-5941 and talk with Ramone.

[KenshinX]

Hmm I may do that. I just called shox.com and found out that Im running stock sized 240z struts and that the Bilstein P30-061 are no longer available. and that the P30-032 are from a vw (which i already knew from reading the thread) but they are much shorter then what I am running and I dont want to do anymore modifications. So he suggested I run the Tokico Illumina BZ3015 for $129.99 each shipped which I think is a good price.

 

Now the Tokico would be my second choice if I can take JohnC advice and send off my struts and get them redone it would be cheaper and probably more durable not to mention I know for sure that they fit and work.

 

lastly If I can get in touch with design production racing I'll order those camber plates with the 3/4" bearings as well.

Edited December 27, 2010 by KenshinX

[JMortensen]

The modification you would need to run the Bilsteins is nothing more than installing a spacer to fit under the strut cartridge. IMO Bilstein>Tokico, and I certainly think that is true of the Illuminas, but you're right that you wouldn't need the spacer with the Illuminas.

[surfer.tech]

If i wanted to run P30-032 on my 240z what springs would everyone recommend?

[johnc]

If i wanted to run P30-032 on my 240z what springs would everyone recommend?

 

Start reading: http://forums.hybridz.org/index.php/topic/50944-the-strut-thread-koni-illumina-tokico-carrera-bilstein-ground-control/

 

We're not going to hand it to you, you need to figure it out for yourself.

[260DET]

This is the sort of setup incorporating a thrust bearing I was talking about http://www.datsport.com/suspension-front-camber-plates-thrustbearings.html Mine are a similar design from memory but anyway there is no side load or angularity on my springs at all. I personally would not have the 'monoball only' type on my car, its second rate engineering in my opinion.

[JMortensen]

As well as a monoball there it should have a thrust bearing for the vertical load which should not be carried by the monoball. Some cheap aftermarket strut tops don't have that, see an OE setup as to how it goes together.

 

This is the sort of setup incorporating a thrust bearing I was talking about http://www.datsport....stbearings.html Mine are a similar design from memory but anyway there is no side load or angularity on my springs at all. I personally would not have the 'monoball only' type on my car, its second rate engineering in my opinion.

 

Richard, you're contradicting yourself. The first one says that the vertical load should not be carried by the monoball. The second one has a bearing to allow for steering to be handled separately, but the vertical load still goes into the monoball. The idea behind the thrust bearing in the Ground Control, EMI and other plates is to put the vertical load on the needle bearing and isolate the monoball so that all that it has to do is handle the angularity change. It has the side benefit of handling the steering as well. FWIW, I had the old style GC plates in my car for 40K miles and although grit did indeed get in there, they still worked pretty smoothly when I took them off and I sold them to another member here who is probably running them right now.

 

I think the more important issue than the steering load is the vertical loading, which when put into a 5/8" monoball is asking a bit much of the bearing, but a high quality 3/4" ball should hold up OK. The spring angularity issue comes from trying to use a needle bearing to take the vertical load. The new GC plates allow both the needle bearing to take the vert load and for the top hat to stay inline with the spring. The EMI, old GC and probably some other plates hold the top hat rigid so it doesn't change angularity with the strut, and this is where you get the side load on the spring.

[260DET]

As I said Jon, "mine are a similar design from memory", similar in that there is a proper sealed thrust bearing in them to take the steering load. Its several years ago that the design of mine was discussed with the custom builder, at the time it was difficult to get my head around the design, sorry I can't now recall exactly how it was done so I can't say for sure that the thrust bearing does not sit up against the monoball. But what I can say for sure is that on mine the monoball does not rotate with steering input. Which is a good thing.

[JMortensen]

I think that answer doesn't make sense. Just thinking about it logically I'd like to see how the monoball does not rotate with steering effort. Once you tighten down the nut on top of the strut, it forces the strut to hold tightly to the monoball. If you turn the wheel, when the strut housing turns at the bottom, there is no way that the monoball at the top can resist turning unless the shock shaft turns, which is what the site you linked to says they are trying to prevent with their design. If you isolate the vertical load from the monoball then presumably the monoball will spin more freely and that will ease up the steering effort. I don't think there is a way to put a monoball over the shock shaft to allow for angularity changes and not have it also turn with the strut. You'd have to have some disconnect in there, or have the monoball itself mounted inside a bearing so that the outer race of the monoball could rotate in its housing while also allowing the strut angle to change, which is something I've never seen before. Even then it might move radially if the twisting force was high enough for some odd reason.