I don't like electric assist stearing.

As *opposed* to your original position there were no articles to be found? What happened there?

Point conceded. However, your original post didn't claim to be unhappy with the *degree* of understeer; you were in a state of high dudgeon that understeer existed at all, claiming the Boxster had none. As you continue to research this, I think you'll find that the Z4 steering tells you as you're about to lose it. What I've read about the Boxster is that you're in complete control until, suddenly, things are hopeless. Weird how high the 3-series placed on that list you posted. Less understeer than a Lotus Elise? epbrown

Reply to
E Brown
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They will. Since switching to my Goodyears, it takes a lot of silliness for my little triangle to start flashing. On the run-flats, hitting the on-ramp aggressively did it every time. epbrown

Reply to
E Brown

Maybe, but won't change the handling *balance*

Both of which will increase understeer. ;-)

Reply to
Dave Plowman (News)

Reread what Fred wrote because he's absolutely correct. *Your* proposed antiroll bar changes on the car will simply aggravate your problem. Hopefully, the sheer number of those of us pointing this out will convince you.

If, OTOH, you are a sworn Disciple of the Denizens of Dinan, give them the list of suggested changes above and ask them about it. I've met (actually, 'had dinner with') Steve and he's not an idiot. Although he'd love for you to buy a whole suspension package from him, I don't think he'd lie to you about the effect of those simple changes on understeer/oversteer. If you want a more tailored approach, you might contact my old pal, T.C. Kline, since he's done a lot with the Z4 in the past few years. You can tell him I sent you.

-- C.R. Krieger (Knows they all understeer)

Reply to
E28 Guy©

Next time you have dinner with Steve ask him to clear up his web site which states: "adds larger and adjustable front and rear anti-roll bars to reduce body roll for superior handling. The adjustable anti-roll bars provide the ability to fine-tune the system for closer to neutral balance reducing understeer. "

You may also ask him to tell his engineers not to suggest roll bars to help reduce understeer.

Reply to
grinder

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Not if selected and adjusted correctly.

Reply to
grinder

I wasn't talking about balance. The added traction of soft sidewall tires will help reduce slip.

Only correct if incorrect sized roll bars are selected.

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we mentioned, the anti-roll bar helps increase the mechanical downforce of the outside tire during cornering. This increases the traction of that tire, and that end of the car (front or rear). An increase in traction at that end, may leave the opposite end with too little traction. An imbalance of traction occurs, and one end of the car will lose traction before the other end. If the front tires lose traction before the rear tires, the car will understeer. If the rear tires lose traction before the front tires, the car will oversteer. Changing the anti-roll bar stiffness can adjust this out.

According to Dinan engineering:

"adds larger and adjustable front and rear anti-roll bars to reduce body roll for superior handling. The adjustable anti-roll bars provide the ability to fine-tune the system for closer to neutral balance reducing understeer. "

Reply to
grinder

Judas Priest!!!! Repeat after me: "I KNOW they all understeer."

Now for the last time let's say this together "it's a matter of degree!" The difference between the balance of my Mini S and my Z4 allows me to corner better in the Mini.

Reply to
grinder

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"The anti-roll bar reduces body roll to keep the suspension geometry, and ultimately the tire, parallel with the road. Stiffer bars reduce body roll more, but too stiff a bar can deteriorate independent suspension performance, and ultimately cause an inside tire to lift off the ground during hard cornering. The anti-roll bar can also be a major tuning element in reducing excessive understeer or oversteer. Used INCORRECTLY (my emphasis) it can also cause it."

I don't intend on using them INCORRECTLY. Of course you and whoever are certainly entitled to do so to prove your point.

Reply to
grinder

Dinan's website is doubtless correct. It's your interpretation that's wrong. Relatively stiffer front bars will increase understeer. Relatively less stiff front bars will decrease it.

Since nothing comes for free, decreasing the stiffness of the front bar by itself will also increase body roll.

JRE

Reply to
JRE

If the result of the selection and adjustment is a stiffer front bar and a softer rear bar than the ones you have now, the car will understeer more.

JRE

Reply to
JRE

Yes. Stiffer front *and* rear bars will increase lateral transfer and reduce body roll. The adjustability can be used to change the balance of the car by making the front bar *relatively* less stiff than the rear one to decrease understeer.

JRE

Reply to
JRE

At both ends. Resulting in the same understeer. It might improve the steering response, though.

I'm only commenting on what you've written. Increasing roll stiffness at the front increases understeer. As does reducing it at the back.

It's not for me you need to quote this. You need to read and try and understand it. ;-)

Actually just adding larger anti-roll bars is a bodge which will spoil the ride. Camber changes are a better way to set about it.

Reply to
Dave Plowman (News)

Maybe, but it depends on the car. The OEM tyre sidewalls for the NSX are stiff to the point of being damned near solid, but they have a soft compound tread rubber set in a bias pattern. With non-OEM tires (ObUS) on this car, there is a 'slingshot' delay effect in the handling which is really nasty. It's completely absent with the correct tyres. Obscure trivia, but I'm in an obscure mood tonight.

Reply to
Dean Dark

Missed the start of this but I have just test driven a 2006 E65 7 Series. The steering is very light but positive. At low speeds it's a kin to Jaguar XJ but at higher speeds it does stiffen up slightly and is nice but going from my E38 to the E65 takes getting used to and moving back to the large (by comparison) steering wheel of the E38 and heavier steering makes me want to go back to the dealer and say "I'll take it".

However, there is a little matter of "where do I get the £40K from..................

Sir Hugh of Bognor

The difference between men and boys is the price of their toys. Intelligence is not knowing the answer but knowing where and how to find it!

Hugh Gundersen snipped-for-privacy@h-gee.co.uk Bognor Regis, W.Sussex, England, UK

Reply to
hsg

Could be. Most of the reports I've read when changing from OEM run flats to 'conventional' suggest comfort is the main gain.

Reply to
Dave Plowman (News)

BMW of course stuck with steering boxes on their larger cars long after the rest of the world went to R&P. Something to do with our US cousins not liking too positive steering on this sort of vehicle, IIRC.

Tell me about it. ;-)

Reply to
Dave Plowman (News)

Read the post from E Brown.

Reply to
grinder

Read the post from E Brown. Also when I went to conventional over ride flats on my Mini S the handling improved dramatically AND the noise difference was huge. It was like going from a go-cart to a limo.

Reply to
grinder

So the handling went from excellent to dreadful?

Reply to
Dave Plowman (News)

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