I agree that getting the balance right is key, and too stiff on the rear can make a car tail-happy.

It could be that the Korean bar on the front, and one of the stock bars on the rear will be a better option with the F-Types. To not go overboard on the rear. It really needs to be tested, what works on the XF (and apparently it works very well) might not directly translate to the F-Type.

The main thing I wanted to put across is, there are a selection of different factory bars, and one option for aftermarket ones. So there are options if someone wants to pursue it.

Has anyone got any pictures of an F-Type being thrown hard into a corner on a track? This was the kicker for me with the XJR that something needed to be done.

The body roll you feel from behind the wheel might not be that bad when you see the stance of the car from the outside.

 

a stiffer bar up front will just add understeer off throttle

i honestly think people are wasting their time on sways for f-type

 

Cambo - I am curious if the Project 7 has a unique sway bar (which Jaguar's marketing materials imply). Please can you look up the Project 7 Sway bars and see how they compare with 2015 R:

Project 7 VIN: SAJWA7A8XGMK27463
2015 R VIN: SAJWA6DAXFMK20231

 

Took me a while but I got there in the end...

The Project 7 does indeed have different sway bars to the other F-Types...

However....

Project 7 front sway bar = C2Z3523 = same as XF 2.0L Turbo, 4.2, 3.0 and 5.0 Naturally Aspirated models

Project 7 rear sway bar = C2D22337 = same as XF Sportbrake, and the F-Type Convertible without Continuous Variable Damping

Ummm......

 

Do I understand you correctly that the Project 7 rear sway bar is the same as the base F-Type convertible?

 

Yes, that's what the parts catalogue says.

However the springs and shock absorbers are unique to the Project 7, no shared parts with other models.

I should have said "a separate listing for sway bars in the catalogue"

 

Just an update on the topic of sway bars.

A friend of mine, also a forum member, has an XJR like mine, but the air suspension was replaced with coilovers from Arnott, which are very soft, much more "comfort" than sport. (I can attest to this, I went for a ride in the car a few weeks ago and it was like riding in a Rolls Royce, could not believe how different it was to my car)...

Anyhow...

He's just fitted one of the front swaybars from J-Craft in Korea, for the time being the rear bar is still the stock one. He's reported that the body roll is gone and the car is handling much much better than before, the poor handling which resulted from changing to the soft coilovers has been fixed.

So that's two positive's to report so far, one from an XF, one from an XJ, hopefully more to come.

What we really need now is a picture of the stock front bar from an AWD F-Type, p/n T2R7849, to see if there was any changes to the design of the bar, perhaps in order to clear the front differential. It's not known at this time if the unique bar for the AWD F-Type is because of a difference in stiffness, or because of clearance issues...

The front bar on the RWD models, exactly the same fitment as the XF, XK, XJ, etc...

 

That would be nice to know. That might be an upgrade for the RWD worth playing with.

 

Would also be good to know if the J-Craft bars will fit an AWD model.

Obviously i'm not going to buy one just to find out... but i'm sure someone could.

 

Did anyone get a chance to try these (the Korean sway bars) yet? Unfortunately I've been riding in my boss' 991.2 Carrera most of the past week and I'm craving some of that 'chuckability' of the Porsches.

Would these help significantly? Does anyone have any thoughts regarding changing both or just changing the front (mentioned in this thread that the Project 7 has the same rear sway bar as the Base)?

 

On the topic of handling improvements, I believe in the F-Type R AWD case, I found that the Dive was probably the worst part of the whole package under hard braking. It's not that big of a deal, but the brakes get overloaded pretty quick when they are running a bit hot (lots of weight to slow down). Swaybars are not going to help with Dive/Squat but Springs will help with it as well as with body roll. My thoughts are that it would be better to update those with higher spring rates (SVR Springs or maybe Velocity) in order to clean up the handling.

Just my .02

Cheers

 

I don't know if anyone has put the J-Craft sway bars in an F-Type yet, I guess if they had we would be reading about it here on the forum.

I was planning on putting just the front bar from J-Craft in my XKR, but since fitting the XKR-S springs & shocks I'm not so sure it's needed now, but I haven't been round a track in this car yet either, so I may change my mind once I've put it on a track with corners.

 

So I went ahead and installed the Korean front sway bar on my '14 base. First impressions, turn in is sharper and the front end does feel more planted.

Would I say it's a ground-breaking difference? No, not really. But for 500 dollars or whatever I paid for it, can't really complain.

I'm also not sure how much of the difference is because of the stiffer sway bar (34mm solid vs stock which is 34mm hollow) and how much is because of the new sway bar bushings (the sway bar comes with polyurethane sway bar bushings).

I'll continue to post more impressions as I keep driving the car.

 

Sounds like it's only due to the bushings, since when it comes to a sway bar, a solid bar is essentially no stiffer than a hollow bar; it's just easier to produce and weighs more. I can give a technical explanation if desired.

 

Check your math. The hollow tube will be as strong or stronger than the solid bar, only if it has the same mass, not the same diameter. The additional strength will range from 0% to 100% as the diameter of the tube increases to infinity (and beyond).


~Buzz Lightyear

 

Thanks for the report!

 

Technically the hollow tubing would be weaker from a torsional perspective than a solid bar; but given the outer portion of the material is so much more important than the inner portion for torsional strength, its basically a moot point given how thick the walls are on typical sway bars for automotive applications. There's almost no difference between a 34mm solid tube and a 34 hollow tube with a 10mm inner voided diameter. I guess I don't know what math you're telling me to check?

 

Not to worry. Your description here fairly represents the science.


But... just in case you want to see the math: https://en.wikipedia.org/wiki/Second_moment_of_area


Anybody need a cup of coffee?

 

Nope...a Tylenol!

 

If I recall my calculus correctly (a mighty big "if," if you get my drift), and if I also remember my physics correctly (we're now at (if) squared), we can ignore the engineering I may or may not remember correctly and you can wrap your head around it like this:

A 25mm solid bar will have the torsional stiffness of a 25mm hollow bar plus the equivalent bar that would fill the void. If the inside void is 10mm, we just add what the 10mm bar would do to the 25mm hollow bar.

With me so far? I think *I* am ...

Now think of what a 10mm bar adds. Weight, without much stiffness. A 25mm solid bar is marginally stiffer than a hollow one, but if it's a reasonable bar to start with, the extra weight does not proportionally add to stiffness.

If our cars were light, we could quibble over a couple of pounds. They're not.