Clear skies, a running car and AUTOCROSS !!

I'm going to go play, now.

cool!!!
let us know how things went

cheers,

Jeroen

Where the hell is JP with the details?
They only run three lap us there, how long could it take? :-)

Im a little bummed I bitched out and didnt make the drive south. Sounds like fun.

Well, the car is faster.

My co driver was a tenth off the TTOD Z06.
I was ...er...farther back....a life time of 2.5 sec. The ought6 is normally the fastest door slammer at the local SCCA events.

There's more in the car even with the old tires.
It was LOOSE. I have too much camber in the rear.
The inside of the rears was 20 deg hotter than the outside, the fronts were 20 deg cooler than the rears, but fairly even across. Gotta back off the front bar, me thinks.

Someone talk to me about tire pressures. On my 4th run (6 passes on the car) the car was really squirrely. After that run, the pressure had risen 6 psi at the rear. I dropped the pressure back to 28 at the rear and that seemed to help.

Feel free to offer advise, please.

How low can one go on Kumhos?.. and
Does dropping the pressure provide more grip or am I just imagining it.

Everyone got 5 passes and should have gotten more (we did get fun runs, tho). I took nearly an hour to break into the trailer
that holds all the goodies. Someone changed the lock.......keerist.

Nuthin' broke, so it was a good test. SCCA in 2 weeks. We'll be ready.

BTW, Boring Bruce was there with his digi camera, so I might have some pics to bore you all with....film at eleven.

I'm downloading them thar pics now
I rode with JP on his first run & added 3 seconds to it. This was my first time at AX and (Lordy) I didn't know what to expect. (Jim Chambers said I'd get throw'n around alot) I din't fully understand by what alot was I found out! Geeze! JPs car is FAST... I couldn't recover fast enough from one turn before we were into another... head bumping against the back & the top.... shoulders hit'n the roll bar... and then, of all things, my camera went shoot'n out from betwix'd mah legs and under JPs throttle foot We're still fly'n around the corner & I'm hear'n JP "Grab the damn thang"!!
So, there ya have it... The whole extra 3 second story
Oh, and lastly.... I'm hooked. I'll be driv'n mine next time. Pics comin' yer way JP.
Thanks for the great time
bruce

I was there too but don't tell anybody. I'm hoping I beat the guy driving the full size Mercury 4 door (it will be close). Finished 5 seconds behind a stock 1.7 in my 2.5 six. 5 runs--spun out on #1 and screwed up the slalom after that. Hit a cone on #2, spun out again on #4. Two clean runs--both real slow! I added a race seat and 5 point harness since last year and it really helps to be held still in the car. I think my spins were partly caused by the fact that, since I wasn't being flung around as much, the car didn't feel out of control until it was! As JP said, "practice, practice, practice,......".

Jim, send me your email address and I'll send your pics to ya.
bruce
bcaphoto at attbi dot com

Bruce took some great shots....after retrieving his camera. Here's one.

GREAT shot.

I love when people enjoy there 914 on the edge....

I'll revisit your questions above later JP.

Those Kuhmo's roll way over....


B

OMG! That's coool. I love when they cock one at the hydrant!

Nice pict. Looks like a good time!

Bruce was nice enuff not to get any of my more lurid
slides....he,he. here's another

Way too much body roll.

Give the suspension low down...

I know the front bar.

It appears you need to run some stiffer rear springs.

B

Geeze man! any stiffer springs & JP will need to install a shock seat! I'm sure I'm gonna be bruised in the morning but it sure was fun!
bruce

Bruce,


I'm actually semi pissed at JP for allowing you to bring a flying object into the car. I have almost killed people on the race track that where hand holding a video camera and trying to drive while filming.

I'm done now. Glad you had fun. 90% of 914 owners have NO idea what their car is capable of.


B

21 mm front t bars, 180 lb rear springs, 2lb digital camera... OOPS.....what can I tell ya, I screwed up.
I WAS almost kilt....or worse, slow.


I'm reluctant to do stiffer t bars at the front.
The stiffer rears will make the car looser, right?
The second pic is a little deceptive. That corner is off camber.

Where did you have the bar set ??

Your forgiven (dad) next time I'm up there... I'll slap the person who was running grid.


B

ERRR....I was running the grid. he,he

I set the bar just a little passed mid point towards the bar....for lack of a better idea.....now I have a better idea

You have to tighten the front to make the rear stick or transfer weight back there (drop the rear end 1/4 inch)

Did you have the car corner weighted ??

Last weekend when Jeroen and I ran the Orange 3.0 six... I had the 31mm bar set on full SOFT and the back end was still GLUED. I felt the front end was understeering like a pig for my liking. I had 4 options:

1. raise the rear and dump weight forward (easy to do with threaded adjusters)
2. raise the rear tire pressure
3. lower the front tire pressure
4. blow it off because I dont run AutoX in zone7 for points.

I left to get food and Jeroen dropped the front tire pressure. This helped when I made another run. The car is on narrow Hoosiers with 250 rear springs and 22 front Torsion bars.

B

DANG !! My new desktop pic Guess I missed out, too

Korijo it was sunny & 71 deg....you screwed up

Bad:

No corner balance.
By "tighten" the front, do you mean increase the roll stiffness? That is not "conventional wisdom", but if you say so......There are 2 SAAC AXs (sat & sun) in a couple of weeks. I can do some.......tuning.

The front is really stuck nicely. It's no longer skittering all over the place at inopertune moments. Muellers bearings were worth every penny and bead of sweat. My thinking on big front tires is on hold. Now, if I just can make the back end to get with the program.

I asked my co-driver what he thought. Old Chuck says " I dunno, I just drive".... WTF, he does it very well.

Tighten the front:

Stiffen the bar or:
install larger torsion bars

Dont use so much gas pedal. You may be inducing the oversteer.

Can you get me some fenderwell measurements ?? SHIT. You tweaked your fenderwells. I cant give you measurements that will get the car close to balanced without scales.

Do you have the threaded collars on the rear ?? or just the stock Bilstein adjustable "clip" ??

B

Oh..

conventional wisdom is:

Tighten the opposite end that is loose.

If the rear tires are hotter than the front... your sliding the ass end around. Tighten the front or transfer weight back there.

B

Just the Bilstein "clips".

The car is dead nuts even ....ride height at all 4 doughnuts to the ground ....4.5 inches...not very precise, but it's all we gots.

As to the sway bar. I think we talked about this when you were up here (you, me and DD). What you say is the opposite of CW and DD said so....I just listened

No shit the ass is sliding around. I never totaly lost it, but came damn close to one of my pattented tank slappers

Are you on the lowest clip setting for the rear Bilsteins ??

Who was CW ?? Chuxster ??

I'll let you know the next time DaveD gets a 914 over 40mph.. LOL


B

Various things I have read over the years (including sway bar instructions) say to soften the front sway bar to reduce oversteer. This is what I mean by Conventional Wisdom...or raise the front spring rate.

Since we don't run the rear sway bar on these cars, I wonder what is right.

My experience tells me that higher rate springs in the rear make the car loose (oversteer). My experience with the old set up showed that softening the front sway bar decreased oversteer.

I really don't want to add more body roll. I'm hoping that dicking around with tire pressures will get me where I wanna go. I do like it to oversteer a bit and I may not be that far off......

I'm on one clip from the bottom on the rear shox.

Your contradicting yourself:

"soften the front sway bar "

"or raise the front spring rate" to reduce oversteer.

Stiffening the front bar gives you the same response as adding bigger torsion bars. Its just a very fine control over the "amount" you ad versus the big jump a larger torsion bar has. Sway bars have a range that you can ad. Something like this: Set on full soft it has a effective range of: 0-150lbs. Full stiff might be: 200-350lbs.

Just FYI: the person at the AutoX who told me to do the 4 things... is a Indy Car team engineer. I should have jumped when he told me what to do... but again it wasnt for end of year points.

Oh.. most the instructions I read are for 911's.

B

That's you're not "your", damnit.

To keep this simple, I'll do what you say....and report back, of course.

Gotta think on that sway bar as springs thing a bit, but now it's time to shut off my brain.

It was a gud day tho.

Sounds like a great day. You have nothing to lose by setting the bar on full stiff and driving the car around. Then set it on full soft and drive the car around. Should only take about 15 minutes to adjust the bar.

B

We had a significant snowfall last night. F you all in sunny CA.



JP, put a ty-wrap on all four of your shock absorber pistons to check if you are bottoming them out.

Hey JP,

The end that you tighten (either by swaybar or springrate) is the end that's gonna loose grip.
The end that you soften is the end that gets more grip...
(so if you want more grip in the rear, either tighten the front, or loosen the rear. And vice versa)

Since you got the rear tire temps way hotter on the inside, I'd suggest you lower the rear pressure first

One of the pics shows you lifting the inner front wheel, but that you're still having quite a bit of bodyroll at the same time.
That would make me think you have too much swaybar for the t-bars you're running (= get bigger t-bars in front)

I'll post some pics on of the orange car we took out last weekend when I get back home tonight.
It had nearly no body roll (22mm front t's and 250 rear springs and a big 31mm front swaybar set to full soft)

I was pretty amazed how "comfy" the orange car still was. It was definatly not oversprung or bouncing all over the place.

Where did you suffer from oversteer? On corner entry or corner exit?

cheers,

Jeroen

Brad, you have good reason to be and so does JP. THAT will never happen again. The energy & force created by the constant slingshot effect when reversing direction puts so much G force on everything not strapped in including the light camers.

Sorry JP for mentioning it, din't wanna get ya slapped I'll take it fer ya
bruce

I think we are missing the point to this thread big time.
Most of the posts so far have been about dialing in the suspension on ULF. Maybe if he gets it dialed in perfect he might pick up a few tenths, I want him to go after the 2 1/2 seconds left in the car as it sits.

As one who doesn't have a clue about finese on the track, I think we should be trying to figure out how that other guy got within 1/10 of TTOD with the same set up.

I've read the books, watched others, and still don't know why some drivers are faster than me, JP's car is obviously faster than he is (and way way faster than I would be in it) so I be scratchin my haid wondering what the other guy was doing that we aint.
I don't want ot hear slow down to go fast, when I do that all I do is slow down.

Is it timing? is it too much throttle or aggressiveness?
This AX stuff is frustrating. It seems like the action comes so fast that i'm usually a tiny bit late setting up for the next corner, could that be part of it? I also slide my car more than most, maybe I need to be less aggressive and try not to slide at all, JP could that apply to your style also?

Maybe i need to ride with someone who is faster than me, but I'm scared to let someone else drive my car at the limit. JP, have yo ridden in your car with that hot shot driver? What does he do different?

I'm with Sammy. I'm not even in the same ballpark as JP (not even same league) but I too am frustrated. I know I did poorly but don't have much of an idea about how to get better. Probably time to read the books I have gathering dust on the shelf. Reading this thread helps too. The rear of my car was real loose. Turns out I had 32 lbs cold in rear tires, 28 front. If I understand correctly, probably should have been even or possibly reversed. I have stock (non-adjustable) front bar and 180 lb rear springs. It's real hard to anticipate the course when you're looking at it backwards!

Boy, this discussion should take an interesting turn.

It is really difficult to determine what your tire pressures should be based upon a limited amount of knowledge. More info is needed (tires, etc.) However, to me, your pressures seem low for an autocross. Remember that due to the limited amount of time, tire pressures will normally only increase by as much as 4 lbs. during an autocross.

For my car, with 195/60/15 street tires, I normally start with 40 lbs. hot pressure all around and adjust from there.

Paul, I have 205/45x16 on 7" Fuchs. Kuhmo Ecsta street tires.

I agree with Sammy 100 %, but I'm working on 2 things at once. I want Chuck to beat everybody and I wanna learn to drive nearly as well.

I don't get a chance to really watch what he does, nor do I want to interupt his concentration by riding along....tho I should prolly do both.

I KNOW I'm sloppier than him. Tho he hit some cones, I never saw him get badly out of shape...I certainly did It IS frustrating....more butt time, I guess.

Maybe I have to face the fact that I'm a better crewchief than driver....but not yet.

A couple more pics. Say hello to Chuck.

And "the slow guy"

The new trick magnetic number plates were prolly worth a second or so.

OK, a few points here....

What B said in this thread is Conventional Wisdom. Make the front suspension stiffer, and the rear of the car will stick better. I recall B saying the opposite, back at the meet at your place. Could be the beer gettin' in the way of my memory--or of my understanding of the discussion up there. As I recall, we did make a bit of a dent in the supply in the workshop that day...


Now that one is easy to fix! At the driver's meeting, speak up and ask for an instructor. Have the instructor ride with you, and try to pay attention to what he or she is saying. Do this at every autoX for a year--you may be amazed at how much your times improve!! Also, after you've autoXed a handful of times, you will find that your brain actually starts working (a little bit, in my case) again through that adrenaline haze. At first, it is all just happening very much "NOW NOW NOW NOW NOW" and there's no time to think at all--but after a while, you can actually remember where you want to put the car, and how to get it there.


Sammy, one of the most important autoX skills (after throttle steering) is looking ahead. Always know where your next turn-in point, apex, or track-out point is. Look at it. Forget the apex just in front of you--you've already set the car up for it and you're gonna get it or you're not. Where's the track-out? Look at the thing! Once you start looking ahead--really looking ahead--you will not wind up "behind the car" so much.

Anecdote--I was a corner worker out in a long 180-degree sweeper. Tobias Olney came roaring through in his 914-6. He turned the car in, and I saw that he was looking all the way around the corner at the apex. Tobias is a credible TToD threat. (OK, part of it is the car. But he can use that car!) This is not a coincidence!

--DD

I remember the disagreement, but as to who said what, I doan remember fer sure.....what I rememeber is not what you thought you said....got it?

I'm gonna stiffen fuckin' the front sway bar and find a fuckin' parking lot to terrorize, then I'll know that what you thought what you said was not what you meant.....that should clarify things

Let me know when you find the lot, Ill bring some pop and hot dogs, and we'll have a party.

The last AX, I had my front bar set to almost full stiff, and I was understeering slightly. I have street tires and stock torsion bars, so that prolly has something to do with it.

Check this guy out. He's up on 2 wheels!!! Must be a stunt driver!!!
bruce

There's a pic on the PP 911 list that I really wanna steal....anybody know how I do this?

jp,

Sure. Just right-click on the photo and select "save picture as . . ." and then save the picture on your desktop or some other place where you know where to find it. Make sure it has the proper suffix (e.g., if its a jpeg call it 911photo.jpg, if it's a gif call it 911 photo.gif).

douglas

Thanx, Douglas. I was screwing up the naming of the file. Here's the pic. Randy Wells at the Parade bring the inside wheel to new heights......prolly needs stiffer springs or sumthin'.

Thats the old 911 "salute" I rmember watching a old 911 at Lime Rock going through big bend with a wheel about 1' off the ground. Funny thing is the guy was posting some respectable times ( for being on 3 wheels) On a 911 thats from to little rear spring and to much front anti roll bar

Set the car up with torsion bars and springs, fine tune with sway bar.
JP, tire pressures too low. Taking tire temps at ax is almost waste of time as you'll never get them up to temp. Maybe with 2 drivers each getting 5-6 runs, back to back.
Car has too much body roll, needs heavier front torsion bar. As car sits stiffen front bar, keep making stiff until front plows, then back it off. When car is loose (oversteer) decrease front tire pressure, increase rear pressure.
Walk the course then walk it again. Sit in car with eyes closed and drive the course. You cannot think on course, you have to know what turns follow what turns. DD says ride with instructor. Hardest thing to learn is to be smooth and look ahead. Do not toss car around.
When rear is sliding by spinning tires you'll lose 1/2-1 second, maybe longer.
You must stay aggressive and attack. You are either accelerating or braking (in some form). If you are coasting because of indecision on increasing or decreasing speed you are losing time.
The fastest drivers can no more tell you how to go fast than I can. It's a seat of the pants feeling that comes from seat time, seat time, seat time.