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I4 has bigger sway bars than V6?

5.7K views 16 replies 12 participants last post by  JCamry94  
#1 ·
Just scratching my head over this one. Has anyone noticed that the in gen3 - 3.5's, the I4's have bigger sway bars than the V6's. Why is that? My guess is the heavier V6's have stronger spring rates, they don't need as bigger bars. However, if one has stronger spring, and smaller sway bars, and the other has softer spring, and bigger sway bars, wouldn't that give both the V6, and the I4 the same level of handling? There's not that much difference between the front sway bars. About 23mm front for the V6, and about 24mm front for the I4. However, the rear bar is much bigger in the the I4. About 15mm for the V6, and 17mm for the I4. The only exception would be the SE V6 which uses a 17mm bar just like the I4.

So then, if I had the V6 (which I don't), couldn't I just install the front and rear sway bars from an I4 on my V6. Or, are there major differences in the chassis configuration between the I4 and V6 that wouldn't allow the swap?
I don't see any major differences, but I've been wrong before.

I don't know, just somthing I've thinking about the past few days.
 
#4 · (Edited)
The rear sways would definitely fit. The front should too cause the suspension is the same. I dunno about you, but I had a 21mm Whiteline rear sway, it was WAY better than stock.
21mm? What's the part number of that one? The only Whiteline RSB I've found for my 96 is the 18mm BTR36.
 
#3 ·
upgrading from 15-17mm wont give you enough difference to go through all the hassle of labor for ... you would want to get something upwards of 19mm, IMO

also, you would want to downgrade your FSB for better handling (more body roll, but less understeer - a good trade-off, if you ask me)
 
#8 ·
upgrading from 15-17mm wont give you enough difference to go through all the hassle of labor for ... you would want to get something upwards of 19mm, IMO
This is only my 2nd post here and yet I'm already committing the faux pas of digging up a 3-year-old post from the grave! :facepalm: However, as an engineer, I feel compelled to comment about the relative stiffness of the 15mm vs. 17mm bars.

A 2mm difference doesn't sound like much, but if two sway bars are otherwise the same (shape, material, solid vs. hollow) as the two OE bars should be, the torsional stiffness is proportional to the fourth power of the radius. So, here's what you get:

  • 15mm: 15/2 = 7.5; 7.5^4 = 3164
  • 17mm: 17/2 = 8.5; 8.5^4 = 5220
  • 5220/3164 = 1.65
Thus, the 17mm bar is 65% stiffer than the 15mm bar. Doing the math again, the Whiteline 18mm bar is 107% stiffer than a 15mm, and 25% stiffer than a 17mm. So, you can see that even a meager 2 or 3mm increase in diameter can provide a significant change in stiffness.

-Shawn
 
#11 ·
Is there anything any stiffer about wagon rear bars? I know the springs are heavier. Just wondering if finding and installing a set of Whiteline bars would be worth doing on the wagon?
 
#12 · (Edited)
Sway bars should be the last thing you change. For the most part, anti-sway bars do provide reduced body roll, but they have the unfortunate habit of reducing suspension independence as you increase the torsional stiffness.

The best way to reduce body roll is to use a stiffly sprung linear spring, then use a much smaller sway bar or none at all. They are good at keeping the wheels from leaving the pavement during hard cornering, but I have a hard time believing the Camry will put a wheel up with its cushy suspension.

I suppose most people go for sway bars because they're the easier to change, but just remember that the higher stiffness you use, the less grip you have available. This is because the torsional stiffness acts as a catalyst and pushes the tires closer to their limits. That's why if you increase the rear bar stiffness, you lose rear grip faster, and gain oversteer as the fronts will have more traction.
 
#13 · (Edited)
That's why if you increase the rear bar stiffness, you lose rear grip faster, and gain oversteer as the fronts will have more traction.
That's not entirely true, at least it wasn't for me. Where I am half of the year you are driving on a loose surface, and have very little traction anyways. In the winter it's snow, then comes spring and it's dirt left over from snow removal.

On a loose surface I found that the body roll had enough momentum in the rear to kick the wheels out under an aggressive turn, The TRD rear swaybar prevented the rear from gaining enough force in turn to do that, as easily.
 
#15 ·
Shawn, you're right, of course. Most spring manufacturers don't really change much, but the Camry could use a stiffer rear spring anyway. I regularly see Camrys nearly bottomed out with 3 people in the rear and maybe some stuff in the trunk. I think Toyota made it a bit TOO soft. Couple that with the weight change on acceleration, and it looks ridiculous. :lol:

I've been playing with my sway bar endlinks on my MR2 because I had this nagging issue: front end washout and extreme tracking. The endlinks weren't adjusted to the new ride height (approx. 1.6 inches lower), so because the endlinks were closer to the bar and strut housing, there was even more tension. I had to lengthen the endlinks to make them parallel with the strut and increase the leverage. Now, the front tires don't washout resulting in improved balance and the car doesn't track as heavily. Steering effort has also been reduced, so I can flick the wheel again. Having to fight with the car is never fun.