I have taken a couple of rides in Sydney taxis that have passed a million km, same engine…
One reason is that the cars never get too stressed (big 4.7 L straight sixes) and the engines almost never cool down: passed straight from day shift driver to night shift driver, with oil changes fairly regularly and major overhauls maybe only once every couple of years or so.
Best way to make your Camry handle is to buy a Mazda Miata or a BMW Z3.
[quote=“redwagon”][quote=“StreetSpec”][quote=“redwagon”]Be very careful selecting aftermarket springs as most of them are much shorter than stock for the ‘slammed’ look the ricers like, but have softer rates to keep the car somewhat comfortable. What you end up with is a low car that looks cool, handles like shit and scrapes on everything.
If you tell me what car we are talking about here I might be able to give you some recommendations.[/quote]
no, I don’t want to lower my car, just want to make it stiffer, less body roll and bouncy…the car is 6th gen camry btw
yeah, for koni sport package adjustable, one shop quote me $33k including sturts, springs and installation…$27k if without spring…KYB new SR is about $3000 less…not that much different so which one would u choose? …[/quote]
For 3k I would step up to the Konis. Koni is imported officially by the same company that imports Vogtland springs. They are good springs (quality) but check carefully the data. I had a set on my old Impreza and half my teeth fell out. Seriously. It was a great setup if I drove flat out all the time, but if I tried to cruise on them I’d get out of the car an inch shorter. They may different products available but the ricers here almost always go for the full race version of anything. Go no lower than 20mm below stock height and spring rates want to be no more than 30% higher. Vogtland is one of those ‘black box’ companies that will not divulge spring rates. They wouldn’t even tell me the rates on my GC8 springs which they had stopped making. :raspberry:
I would let Sulavaca have a look at the car for you to see if it’s just built-in factory wallow or if something is loose / worn / broken down there. My experience with dealers is that everything is normal as long as the car is in warranty. 
[/quote]
while in general this is good conservative estimates, you can go WAY higher than that on spring rates as long as your dampers are properly setup for the springs. as an example i ran 675lb/in front and 850lb/in springs in the back of an m3 (stock something like 250/200) and it was fine. totally streetable. removed the rear bar tho because you really don’t want a bar on the driven wheels if you can avoid it. making effective rate in anything but pure bump less than the >400% of stock as it appears here. the front however also had a gigantic bar to combat the macpherson-strut badness.
you can also go as low as you want as long as;
the problem with most setups is they either don’t correct geometry, run shocks or bumpstops that are too long, or run dampers that are nowhere near enough damping for the spring rates.
btw, for what it’s worth, the knobs are either totally non-linear or altogether useless on anything but a penske or maybe jrz shock. i ran koni doubles for a long time but had them revalved to work with the springs. then i tried penskes and the difference was astounding.
a camry has i believe the same double macpherson setup as a subaru. which is to say it’s not that great of a suspension geometry from the beginning, but cost effective and simple. the main thing is in what the factory chooses to put on the scale of comfort versus performance (and nvh).
so suggestions on taking some compliance out of the suspension before going too nuts with the shocks/springs are probably right on, although yes it can and does spiral out of control especially since the aftermarket stuff is typically more aggressive than what the factory would use in a factory “sport package”
I think the Z3 is horrible compared to the Z4
Remember that each car has a different motion ratio, so directly comparing spring rates between platforms can be misleading. On a strut suspension the motion ratio is very close to 1.0 (.966 for the GH Impreza). From this you can calculate the wheel rate (effective rate at the wheel). Multiply the spring rate by the square of the motion ratio, thus on a (McPherson) strut suspension the wheel rate is very close to the actual spring rate. On a double wishbone (or other non-strut) setup the rate is less than 1.0 as the spring is further inboard and has a longer lever operating it.
Using a new Impreza WRX as an example the front rate of 216lbf/in multiplied by .966 squared (.93) = 202lbf/in front wheel rate. The rear spring is 194lbf/in times .78 squared (.62) = 120lbf/in effective rear wheel rate. It’s obvious the motion ratio in the rear drastically changes the overall rate and that’s why you were running much stiffer springs in the rear of your M3 compared to the front.
Also, there can be huge difference between final effective rates between a fixed perch strut and a coilover in a McPherson configuration. So how the car feels is dependent on many factors outside of raw spring rate and one of the biggest factors is the weight of the vehicle. A 675lb spring on an M3 is going to give a very different ride from the same spring on a Civic!
Of course it is most important that the dampers be selected to work with the spring rates you’re planning to use. This is where a lot of projects fail. A great many people want to lower their car but don’t understand the whole system. They look at springs and think they can go to shorter springs and only increase the spring rate a little, trying to maintain comfort, and try to save money by keeping their OE struts and shocks. The shorter springs also reduce available bump travel, which in and of itself is not necessarily bad, but fail to realize a much firmer spring will be needed to keep the car off the stops. The right way is to consider the weight of the vehicle, the intended use, the motion ratios front and rear, and then decide on a spring rate. Required damping force is then easy to calculate.
I’m not sure if I agree with you about rear bars in general, but the M3 does have a lot of power and I’m sure oversteer is a big concern. I like to use the swaybars to fine-tune the handling bias of the car once springs and dampers are correct and by classic suspension theory I’d have said you had too much spring in back if you had to remove the rear bar completely. The last time I tuned a BMW it was an E30 M3 (with a T4!) so I’m probably way out of date with this idea.
Pretty much. What many people fail to realize is that lowering via fitting shorter springs to an existing damper maintains the same total suspension stroke (unless there is coil-bind) but that the car now has a static height that has the shock much further into it’s bump stroke. In other words gaining droop travel but losing an equal amount of bump stroke, and as you say, that puts the shock body close to the bump stops. While shortening the bump stops is an option (replacing them with shorter, stiffer items is better) it will shorten the life of an OE strut quite dramatically by forcing it to operate constantly in this area of it’s total stroke. The solution is to fit shorter dampers along with the springs, but the necessary corollary there is that the new damper will have less total travel. No problem in a car that will just see track use but it will be an issue on the street.
As you mention, many people run short, stiff springs on the OE struts and are then surprised they have ‘ricer bounce’, wallowing in corners, bump steer and perhaps not as much reduction in body roll as they expected.
As you mentioned in point 2, many cars exhibit worse handling when lowered beyond a certain point. One common mistake is to lower the car so far that the center of gravity drops below the roll center, introducing more body roll rather than less. It’s also common at this point to find that the angles of the track rods are suboptimal at the new ride height which can introduce bump steer and other unpleasant side-effects, requiring another round of modifications like moving the steering rack, the control arm pivot points, fitting offset track-rod ends etc.
So ‘as low as you want as long as…’ might only be 10 or 15mm, depending on the car!
I found that non-linear range on the KYB adjustable struts I installed on my old Impreza but the Konis are quite linear and I’ve seen the shock dyno graphs that show that. So, knobs half way on a Koni is very close to being the halfway point through the damping force range of the shock. Perhaps being revalved changed that for you. All standard disclaimers apply. 
[quote=“mabagal”]
a camry has I believe the same double macpherson setup as a subaru. which is to say it’s not that great of a suspension geometry from the beginning, but cost effective and simple. the main thing is in what the factory chooses to put on the scale of comfort versus performance (and nvh).
[/quote]Yes, the Camry has a McPherson strut in back with double links, somewhat like an older Subaru. All the new Subies have double-wishbone rear suspension btw, except the Group N rally cars. The advantage of the McPherson strut in back is the possibility to build in much more travel, which is a plus on poor roads if comfort is a priority. It is harder to make this system handle well but it can be done, albeit at the expense of quite a lot of travel. Long travel on this setup makes the camber range wider and at full droop the positive camber can be horrible, not to mention the effect that has on traction. 
So in summary I’d say that if the OP wants his family car to handle in a semi-sporty fashion, he should be in an Accord or a Legacy rather than the Camry.
To the OP: Although Red gave the definitive answer, the quote above is the only part you need to pay attention to. I can promise millions the world over have buggered around with their stock cars and almost always been disappointed in the final cost of making it just right over a car which just does the job in the first place. This is also why modded cars are usually worth a lot less than standard on the used market.
Leave it alone and just change your car if you aren’t happy with it. Assuming it doesn’t have any faults at present which are causing any uneasiness.
redwagon, totally on the motion ratios, but i did it as percentage of stock spring rate to compare directly.
fwiw in the m3 example, off the top of my head with effective wheel rate was something like 650F/550R sans bar (pure bump). with giant front bar in turn, a lot more. the challenge as you alluded to with macpherson is to keep the camber where it needs to be given how bad the mac strut is when it starts travelling. what a lot of people, including me, do with macpherson is to get it as close to not moving at all (within what the surface and tire stiffness permits) and as low as geometry, surface, clearance allows with the main driver often being “can i get enough camber to keep the tires happy at this ride height”.
the car also was 2720lbs, had something around 400-450hp depending on altitude and fuel, gobs of torque (it was a twinscrew’ed motor) and hoosier 315s logging around 1.2-1.5g sustained depending on surface, so the rear needed to articulate to get it to behave on corner-exit power-on. as it was the car was nearly bicycling the transient stuff and had less aggressive of a ramp on the diff as many run to optimize power-roll-on behavior, so anything to keep the inside rear on the ground helped.
so anyway, that was my setup. it worked well enough in racing to make the car a threat for solo2 national titles (we put it 2nd fastest one year in the always crazy street modified class) and it worked on the street.
i write all of this to say if you really want to, you can all the way to a competent weekend warrior, streetable car. which is to say, you CAN improve a camry, although it is not the ideal platform to try… neither was an m3.
to the op:
redwagon and sulvaca are right on suggesting you get an accord if you want a similar car with better handling. the simple reason why is that its upper-control-arm suspension make it a better starting point. the somewhat goofy setup i had on the m3 was because of the peculiarities and badness of macpherson strut. on your camry you have to deal with four of them instead of the usual front macpherson, rear a-arm/multi-link with upper-control-arm. sure, wrx guys have also had to deal with this also and many got their cars to handle ok, but it’s a reason why the subies always handled worse than the evos in street situations. and also why nissans were worse than hondas.
another totally good option is to leave your car as is and use what you would have spent to attend a real performance driving school. you will be surprised how much you weren’t getting out of your car before.
another way to make a handle for your Camry is to taken a nice large crowbar, bend it into some usefully handle-like shape, and then weld it to the roof.
You’d need big hands and super strength to lift it, though.
on the shock linearity, the singles are ok for the very middle of the range, but pretty bad at the end points.
but then again they are singles and rebound adjustment alone is a bad way to go about things when dialing it in.
on the koni double adjustables i was running (the 8711 DA), the low and high speed rebound and compression are mixed into one knob for compression, one knob for rebound, which causes a lot of having to fiddle to get a compromise for a surface.
other than having a funky nitrogen charging procedure, the penske triples and quadruples are really really works of art. they are also easy to self-service, which is good for changing valving yourself as needed.
heres a good breakdown that with dyno plots of the various shocks: bit.ly/9QCYHJ
and always fun to mention when taking about shocks “f1 dampers don’t have knobs”. they have 7 post rigs and track simulators for that. 
all good advises tks…
[quote=“sulavaca”]To the OP: Although Red gave the definitive answer, the quote above is the only part you need to pay attention to. I can promise millions the world over have buggered around with their stock cars and almost always been disappointed in the final cost of making it just right over a car which just does the job in the first place. This is also why modded cars are usually worth a lot less than standard on the used market.
Leave it alone and just change your car if you aren’t happy with it. Assuming it doesn’t have any faults at present which are causing any uneasiness.[/quote]
[quote=“mabagal”]to the op:
redwagon and sulvaca are right on suggesting you get an accord if you want a similar car with better handling. the simple reason why is that its upper-control-arm suspension make it a better starting point. the somewhat goofy setup I had on the m3 was because of the peculiarities and badness of macpherson strut. on your camry you have to deal with four of them instead of the usual front macpherson, rear a-arm/multi-link with upper-control-arm. sure, wrx guys have also had to deal with this also and many got their cars to handle ok, but it’s a reason why the subies always handled worse than the evos in street situations. and also why nissans were worse than hondas.
[/quote]
I’m gonna wait for the new facelift accord, should due this year…legacy is still out of my reach unless I sell both cars…I have no problem selling the camry…but I dont really want to sell the other one coz I like the way it handles and the overall look
RW, what do (or did) u do for a living? u seems to know everything about car, in and out 
…I know what Sulavaca do or did before so I’m not surprise if he knows all about car or anything with wheels
no it doesn’t have any faults, just dont really like the way it handles…infact, I like the outlook better than the new accord…the new accord also got that hard plastic dashboard + AC/radio display at the bottom + no flat floor at the back, all which I dont like but it handles much better…
[quote=“StreetSpec”]
RW, what do (or did) u do for a living? u seems to know everything about car, in and out 
…I know what Sulavaca do or did before so I’m not surprise if he knows all about car or anything with wheels 
[/quote]
I’m just a cranky old mechanical engineer who used to design gear transmissions for a living, so I guess that makes me a retired gearhead. Sulavaca is far more knowledgeable than I am on the real day to day quirks of a very wide range of vehicles as he’s been hands-on for a very long time. I only worked in the auto industry for a short time on the service management side and later in production line automation project management. On the more fun side I got to dabble in preparing vehicles from 2-stroke production race bikes to cars for saloon car racing and hill climb events along the way. I still work in manufacturing, but not in the automotive field. I’d now call myself an enthusiast tweaker of the ‘dangerous amateur’ type.
Hope none of that sounds too self-aggrandizing.
ah that explain all your knowledge about car handling
not at all…