chronohunter

iTrader: (1)

The other issuse with bars is they are undamped. Great shock like Ohlins are mandatory for making the EVO work especially with the big rear bar. The truely amazing thing is that they actually ride a little better than stock even with the much increased spring rates. As a next step I would like to try the Cusco rally front bar which is half as stiff as stock and go stiffer on the front springs. It really is all about finding front grip

Oh and great recommendation about keeping your testing on the track. it is the only place you can drive hard enough and think clearly enough to feel this stuff

chrisw

iTrader: (2)

Thanks to ogvw, I can personally say how great these coilovers are. truely amazing. I am running some pretty significant spring rates and feel like I can easily go with even higher rates and still maintain good on-street performance.

These coilovers are simply the best mod I have done on my car to this date

Getting back on topic, this thread is one of the best on this forum...

hagakure

iTrader: (2)

I Agree with Robi Here
I do think some other types of experience do help with your "feel" concerning cornering...

P

hagakure

iTrader: (2)

Point well taken...I'll stay safe

Percy

ogvw

iTrader: (4)

With stock springs and bars you are limited to tuning the camber with the lower pinch bolts on the shocks (unless you fabricate a different upper mount to facilitate using a camberplate - but you'd be sacrificing a lot of wheel travel for only a little gain). One good Idea would be to use a plate like this....eccentric 3 position.

Turbo-Ron

Nice explainations guys - many here appreciate it

Interestingly - the skeptics have led you guys to produce better explainations that reemphasize the rationale for your conclusions.

Thanks to all

Doctor Dre

I hope that most of these driving techniques are being performed on a track or Auto X course. There is absolutely no reason that you should be left foot braking on public roads. You would only trail brake to give the front tires more grip so that the car will rotate. By braking your going to get weight transfer to the front wheels which should cause the front wheels to grip even more. However, if this weight transfer is too abrupt this might cause the rear tires lose grip. Be careful

chronohunter

iTrader: (1)

Glad to have you back in Robi and very glad you have an open minded about this stuff. BTW that 240 in OTC was fantastic, now that thing had some corner speed and a damn good power to weight ratio (and well driven). You expect and old 240 to be a bit of a rat trap...not this one.

It's funny you mention the Racecar engineering article because I was going to recommend you pick it up, it does talk in detail about the benefits of trail braking but failed to put it together with the late apex line that makes the technique so fast. I don't ignore overheating the front tire, I don't have a problem with it by minimizing load transfer with the front suspension set-up we use it (using the inside tire more) is easy to manage but always a concern. The fact is EVO will always be limited by those damn front tires no matter how you drive it. We use driving technique to balance the car, you use set-up. Technique can be changed to suit any type of corner, set-up can only be changed in the pits. We can just vary the trail braking from 0-100% depending on the cars needs at that moment and that means less compromise and more speed on the average and as mentioned before its more stable an easier to drive. Trail braking is just another tool avaliable to the driver (but certainly NO crutch).

You still need to come up with a professional source that supports your style of driving. I hope you realize that I drive pretty sideways too but because of our different set-up I can do it all at a higher speed in the same given corner. Isn't that what it's all about (and the tires will stay under the car for the whole race because it’s balanced taking the weight distribution into account and working with it, not against it).

One last point trail braking increases the size of the traction/friction circle, it does not "overload it" it increases its load carrying capacity (that's the advantage). It's good your tire temps are equal that is important the problem is that you have had to loosen up the rear so much to achieve it. Our tire temps are equal as well and again the corner speed will invariably be higher.

As for the magazine guys liking it they are all super nice guys and enthusiasts but none are professional racers and they all love to slide (who doesn’t!). Keep on posting (get Muller involved since he is the source of the RRE set-up).

Good to here from you

Paul

chronohunter

iTrader: (1)

All good points, you can though practice this on the road as long as you do it well below the limit (you can go through the motions to get the timing and feel down).
Be safe guys

Scottybob

iTrader: (3)

I'm sure a few people reading this are planning on going to their first HPDE, track day ect. I don't have nearly the technical knowlege or driving ability of some of the contribuitors to this thread. But I've been instructing HP driving with a nation wide car club DE program, so I'd like to offer some advice to those green group students.

Dont do anything to the car except get a good alignment and a good tire pressure gauge. It will take you several to many DEs to begin to get close to what a stock car will do. Do not add a rear swaybar. In my opinion it would make the car too loose.

I need to make a change to my alignment setting, and I'm still thinking about what it needs to be. This set up was improvable, but driveable. F camber -2.0, toe .1 degree toe out. R -1.5, zero toe.

Do not attempt to trail brake over 70mph (with this alignment setup). I trailed a little brake into a 95 mph turn that I used to trail brake pretty aggressvily in a FWD car. It made for a intresting car control exercise.

Turns out the car seems to pitch into a nice slip angle all by itself on high speed turns, and can be nicely rotated in slower turns.

The car is very sensative to tire pressure adjustment. 2 pounds on either end makes a very noticable difference.

I think some input from our more experienced posters on stock suspension would be intresting.

chronohunter

iTrader: (1)

Again good points all. As we stated many posts ago the faster the corner the less you trail brake to the point that you don't above 3rd gear corners. It is just for slow to medium speed corners. As far as my input is concerned your comments are right on the money as are your alignment specs. For new track drivers the rear bar is fine but start with it full soft and take those life preserving "baby steps" and above all get out on a skidpad first and run around that thing till you're sure your gonna' hurl. No one has any business being out on a track till you can catch understeer and oversteer without any conscious thought. That is the best advice I can give. You don’t want to discover your cars (or your!) “unique” traits through a top-of- 4th gear sweeper and not be sure you can catch it (or better yet anticipated it). Happy tracking

metaphysical

iTrader: (3)

I think I understand what your saying, using basic physics and common understandings of vehicle dynamics, that trail braking is a good technique and will improve your lap times. But, with that being said, are their any real engineers with actual engineering degrees in here? Perhaps this is too basic and just using assumptions on former findings. Paul, don't you think it's possible that with the RRE JICs and the RRE accelerate through the entire turn driving strategy that their setup could be as fast, if not faster than your setup and driving style? Yes, we understand your an incredible driver, maybe the best out there with an Evo, but John Mueller is also an amazing driver. Perhaps his setup with him driving could be faster than your setup and your driving? Is this possible? It seems like everyone (except for Robi) is now saying that the RRE method is wrong and guaranteed to be slower. The tide in this thread keeps steering towards, "well, book x says this, and instructor x who won x said that, so it's the only way to go." Don't you think it's possible that perhaps your missing something, trying to overanalyze over-simplified engineering principals? (No offense, but it's not like we have a team of Harvard engineers here.) Maybe they can't explain it in jargonish words, but it does work, it does win (and as Robi pointed out) it has beat nearly every other setup out there.

Scottybob

iTrader: (3)

Guess I'll leave the alignmnet alone Cant wait to get it on track with some race rubber.

chronohunter

iTrader: (1)

How can I say this without sounding like an egotistical jerk? I do this for a living for the Volvo WC team for my work as a vehicle dynamics instructor Racing instructor Racing driver and a mechanical engineer. I have also do tire and vehicle evaluations for most major manufactures was the chief instructor at the Skip barber Racing School for years. I eat and breath vehicle dynamics and have given talks to and ridden with I would guess over 100k people in 12 years of doing this. None of it matters, you know why? Because you don't trust me, I could have made all this up right? Hell half the stuff I've been lucky enough to do sounds like wishful thinking (B.S.) to me as well! Good example: two weeks ago I was ripping around the Nurburgring in a M3 for a couple of days followed by three days at Michelin's Laurens test track etc. (I love my life )

So what’s the solution!?! YOU go out and buy (or sit on the floor at Borders!) and read every modern day driving book out there. Go talk to any Professional race engineer or driver and ask them. Read a physics book and definitely Skip Barber's Going faster. My obvious point is this is not my idea or the Vishnu shop official driving and set-up that I am professing.

It is the way it is done in any well turned out road race car around the world. That is why I am begging the RRE camp to prove me wrong on this. This all started because Robi said Trail braking was a crutch for an improperly set-up car (in so many words). I could not leave that alone

It's not about whether I am faster than John or not (though I love to race anyone). It is the physics of proper car set-up for the EVO and then how to drive it. Which is safer and faster

shiv@vishnu

iTrader: (20)

Paul's an engineer, among other things.

Beating other improperly set-up EVOs, driven by amateur to intermediate drivers who are still learning the fundamentals of high performance driving does not make you gospel. Running record smashing times at the 'Ring with only 2 days of practice does

But what do i know, i'm probably considered one of those intermediate drivers and i only have a b.s. in econ

Shiv