RON430

Bilsteins got installed last Tuesday, going to be hard to forget that day and not because of the bilsteins. As I have said, I am going slow with my suspension mods. Got the sport bilsteins from will and finally had them installed. No problems in installation on a 2001 even though bilstein doesn't seem to know that yet. Still using stock springs as lowering is not that high on my list. A simple request to Lexus - please get someone else to do your shocks, if nothing else on a sport package. The bilsteins alone remove almost all of the annoying freeway float. There may be some more impact transmitted but it is very hard to tell, my wife cannot notice any difference in ride quality. But you do notice that the suspension both in the freeway float and in cornering is far more controlled. I will use this combination for a while before assessing what I want to change next but if the car had come with these shocks as standard, I would have left it alone for quite a while. I have been a big fan of bilsteins, at least give them credit for understanding what it is they do, and they do it very well. Not saying anything negative about other vendors out there but if I feel the need to lower or get adjustability in ride height, the bilstein coilovers will be my choice. If you are looking for an absolute flat cornering condition, and are willing to accept the ride quality, I would not recommend this setup but if you want a noticeable improvement in suspension dynamics and control with virtually no affect on ride quality, bilsteins and stock springs make a good approach. Not bimmer territory but actually not that far off either.

GS4Will

Hi RON,

thanks for the insightful feedback on the BILSTEINS.

to elaborate your comments on the factory parts, i believe Lexus really SKIMMED on parts such as shocks and tyres that came to our shore. basically they did this to save cost so that cars like the GS can be priced very reasonably. and the fact that lexus some how believe american luxury car buyers stil prefer cadillac-type ride(not that the GS is anywhere near that). luckily these upgrades do not cost too much $$$.

for the european GS, you can actually select a "sport pkg" that is the L-tuned suspension. and if you had look at your BILSTEINS closely, they are actually the OEM for toyota as indicated on the shocks that i sent you.

great to hear that you like the results.

william

2k1GS3

Are you saying the L-tuned shocks are Bilsteins? The same ones that Ron just installed?

RON430

Have to wait to Will to answer that one. I don't remember much about the boxes other than they listed the models they were usable for. I did look at the shocks and I am not sure I would know how to figure out that the Bilstein had any relation to Toyota OEM. The shocks definitely were Bilstein Sport setting. Using the resources on this board I have ordered most of the manuals for the 2001 GS from Steve at Carson, actually Gordon Miguel, also a great guy who I think works with Steve. For no particular reason, I ordered something called the 2001 New Car Features book. It covers the GS and the RX. It covers only changes in the new models. There was a new shock adopted and here is what it says.

"Low pressure (N2) gas sealed front shock absorbers with a linear control valve have been adopted to realize both driving stability and riding comfort.
Through the adoption of the linear control valve, the changes in the damping force are made constant at low piston speeds, thus making the vehicle behave more smoothly in relation to the steering operation. At medium and high piston speeds, the damping force is reduced to lessen the vehicle vibrations in relation to the roughness of the road surface.

The linear control valve consists of a C valve, a cutout valve and a leaf valve. These valves adopt a laminate construction and form orifices. At low piston speeds, the oil flows through the cutouts of the valves to achieve a linear damping force. At medium and high piston speeds, the valves flex to increase the amount of oil that flows through, thus reducing the damping force."

There is a diagram or two of the internal workings and a plot of damping force versus piston speed. The net result, assuming the translation is correct, is that the faster the piston moves, the lower the damping force that is exerted by the shock. The claim is that this is done for ride comfort and that one remark about steering operation (the discussions about vibrations at 55 may take part in this). I must admit that while I was not shocked, I was definitely impressed by the fact that the components in the Lexus are chosen most likely for ride and isolation first and handling a distant second. I haven't looked at the Bilstein site for more detail but I would doubt that they are biased in that direction. I am desperately trying to not get into a placebo comparison here and convince myself that I made the correct decision but I can definitely feel that the suspension movement is far more controlled without much, if any, harshness being transmitted. The disclaimer is that I am a long time fan of Bilstein. If they make a unit for your application my opinion is that you would be hard pressed to find a better unit. There may be comparable units but nothing much better unless you count adjustability in the equation and I wouldn't give up operational correctness for adjustability. I am far less interested in looks which is why I am not too concerned about lowering. If I change springs it will be to alter spring rates and possibly do some lowering of the CG but not to make the tires fill up the wheel wells more closely. My take on the Eibachs is that their spring rates are very close to stock but they do provide the drop. For right now I wanted to improve handling and get rid of that annoying freeway float. Stock spring rates with the Bilsteins seem to be a good compromise between handling and ride comfort. Not sure I want springs much stiffer right now. Also, I have 16s and I am thinking about either going to 235/50-16s or to 17s for footprint and they will both likely firm the ride up somewhat. Like I said, I know the approach I am taking is expensive relative to picking a whole carton of parts from the outset and only having one install charge but I really don't want to go too far on this car. Like the other old fart, Mean Gene, if I want a road racer on the street I will look for something other than a GS. As an ex BMW owner I have to admit that not only the handling of the bimmer but the overall ride is maybe the best in the world. Even there it was improved with Bilsteins and I figure the GS can easily get to the same level, all the right design pieces are already there. Sorry for the long post.

GS4Will

2k1gs3,

L-tuned are made by KYB of japan. they were originally bounded for the european market on the sport pkg GS.

both l-tuned and Bilsteins are good alternatives to the mushy stock shocks. the Bilsteins is a bit firmer. but as RON said, the name says a lot about any products from Bilsteins. many car guys have experience with bilsteins products, so whenever they need suspension components, they take bilsteins with no reservation.

william

GS4Will

Ron,

i drew the conclusion of Bilsteins and toyota from the toyota co emblem on the bottom of the bilsteins shocks. just an observation.

william

RON430

Hey Will,

Geez, I didn't look that close. Not sure what the mark means. Might just be Bilsteins way of keeping track of inventory. I don't know if you ever heard of a shock being modified like the 2001 shocks on the GS as I posted. Reducing damping force with piston speed seems like it would be done to reduce impact harshness from hitting a bump but you give up the shocks duty to damp the spring oscillations. I had never heard of this being done before. At one point or another I have posted that in my opinion you do not need to get a harsh ride to get good handling and Bilsteins definitely prove the point. KYB are very good shocks as well, they were the other licensee of the DeCarbon shock system with Bilstein. I will let things go for a while, the shocks make that big a difference in my mind. May want to increase roll stiffness but that would mean bars. Interestingly, that screwy New Car Features book says they also increased the front bar stiffness on the GS in 2001 and increased the rigidity of bushings on both front and rear bars. Both sound like steps forward but I think they took a step backward with the shock for ride comfort. Nobody's perfect.

Ron

2k1GS3

Wow, Ron, it sure seems like you have put alot of thought into this! Not quite sure how to translate the mfg. info on the 2001 shocks. Bottom line, do you believe the design of there was meant to "tighten up" the suspension from previous years? Has anyone noticed a difference btw 2001 and previous years? For me it is too soft and I am wondering whether L-tuned is enough for my taste--some ppl think it is still too soft. Others like it alot.

Hmmm...now I really dont know what to do; L-tuned, Eibach/Bilsteins, just Bilstein shocks...My primary goal is to tighten up and flatten out steering without losing too much of the comfort of this car.

Thanks for your thoughful insight.

RON430

2k1GS3 - Mean Gene and I go back a long way. Maybe we don't know each other but it seems like we are about twice as old as the average guy here. I started in cars in the late 60s and have a fair amount of road racing under my belt. In my era, "If it don't go, chrome it." was the catch phrase for components added for looks. Obviously, that has changed and there are guys here who are putting together some really spectacular looking and performing vehicles. I am no automotive engineer but I have spent time with the books, always appealed to me, and then tried to sort out the operation and effect on the vehicle. I was a little dismayed with the ride and handling of the GS430 out of the box. There is a considerable freeway whoopdeedip around here and it really put a knot in my stomach going over it at 70 in the GS. The Bilsteins didn't get rid of all the float but I would say that they get rid of 75 to 80%. While I might like it a little firmer, the whoopdeedip does not get me queasy anymore. I haven't noticed any unusual squat or dive characteristics under acceleration or braking and that makes me think the spring rates are not far off (although figuring out stock rates or profiles and comparing to Eibach, H&R, etc. has been impossible). I would like a bit more flatness in the corners but not at the expense of straight line ride. You can just firm everything up or try the components that work mostly in the turns, the stabilizer bars. Front and rear bars (and their links and bushings) have a big effect on what happens in the turns. They have limited effect on what happens in the straights until you start to get very stiff. The stabilizer bar will transmit what happens to one side of the car to the other. If you are very stiff, a severe bump that would effect one wheel, now effects both and you notice it more. I have no problem with this feel in some cars but it is not what I am looking for in the GS. I really don't want the word harsh to enter into a description of anything I do. Natural tendency is to leave on whatever you put on so I am going slow, which is why it will be expensive. It is much cheaper to install everything at once but it is impossible to tell the impact of any one component if you do that. My guess is that when people put bilstein/Eibachs on, the thing they feel most are the bilsteins. Hardest thing to do on a race car is change one thing at a time. When you watch a Nascar happy hour and a guy says they threw everything out and changed a bunch, they really are far off. For me, if the car had come with bilsteins, I would have left it alone for a while ( I still can't believe I changed shocks on a car with 1800 miles on it). But if you want a lot more firmness, it will take more than the bilsteins. I just look at the whole suspension and will try to work with all of it, tires, springs, shocks, bars, etc.

Once again, I would like to apologize for the long post. One of the things that has been great here are the guys who have tried a lot of things and post their results. It can save a lot of money. I think that some older posters are intimidated by the younger guys and their mods but sometimes the older guys have been around and had quite few cars over the years and have really refined what they want in a car. I forget who posted but someone tried different profile and rim size tires and the 225/55-16 gave him the best ride/handling all things considered, that was really a valuable input. If I shorten up to 235/50-16 I get as big a contact patch as a 235/45-17 but should avoid some of the harshness of the lower profile. Like most cars, my gut says some more rubber on the road is a benefit for the GS. Sometimes what looks good isn't necessarily the easiest to live with on a day to day basis. I hope we can have continuing topics for guys who aren't into radical mods but who do want to improve things in the Lexus. From what I can see, all the right stuff is there and just needs some re-orientation from the factory goals which are definitely not performance oriented. And you get that great reliability and build quality.

RON430

2k1GS3 - The previous post got somewhat preachy and didn't really answer your question. I am still going through the "changes" book (thanks Steve and Gordon once again). 57 pages of engine changes alone, then another 27 pages of everything else. Biggest suspension changes are the ones I mentioned. Funny thing is that the RX gets the screwy shock as well but they have a spring inside that assists as the travel gets used up. The GS shock shows the spring in the cutaway but no description so I don't know whether it is there or not. In any event, I think the shock took a step in the luxo ride direction and not the handling direction. The only other significant suspension change is a marked increase in the brake master cylinder piston diameter which went from .87" to 1.06". They also went to a concentric two piston arrangement, if the accumulator fails it only affects the outer piston so you keep a fair amount of brakes. Other notable changes, they added more sound deadening insulation (hard to believe) and the stereo. The Nakamichi was a completely different set of all components but according to the Lexus manual, the Mark Levinson is the same head unit as the stock system. The ML is only a changed amp and speakers. Oh, and for the trivia buffs they now tie a few more sensors into the Body Electronics Area Network which carries the macho acronym of BEAN.