2007 auto-x begins

[mohaughn]

Went to the first autocross in my area today... Had a blast driving the car with the new suspension. Fastest time of the day for me was 45.9. My first run was real slow, 54 something... Even then I'm sure I could easily get another 5 or 6 seconds off of my time once I get more familiar with the car and get used to how the course is setup at this particular location.. I had one of the instructors drive my car and he did right around a 42. There was an M3 in street prepared that was putting down 39.xx consistantly. Fastest time I saw was a 37.4 in a street prepared miata.

I was running in the novice group but payed attention to the cars in XP. One was a shelby cobra replica and the other was a 300zx twinturbo. The fastest time out of those two was a 39.something and the cobra was only putting down 41s... Both of these cars were running r-compounds.. If my car did a 42 with street tires I should be able to compete with 39s on r-compounds...

[mohaughn]

pics.

[mohaughn]

A few more. My car, my buddies 330is with the performance package which is a lot of fun to drive. The XP shelby cobra replica, one of the really fast miatas, and a random z.

[AlaskaBlue]

Looks pretty good. Did you get the suspension worked out yet? The thing I found with my car was that it needed camber plates..badly.

[mohaughn]

Yes. Everything is installed with the exception of the x-brace and the new motor mounts. I still need to get the front wheels shimmed out to 2 degrees negative camber so that I can adjust between 2 degrees and 3.5 degrees for the track. I put a bubble camber tool on to the front wheels and they are showing a little over 1 degree of negative camber.. If I had to guess the rears are up around 3 or so. So there is still some more work needed to get everything dialed in, but I can take my time on doing that stuff while I learn how the car handles... it really is like driving a different car.

[AlaskaBlue]

a good suspension really does make a big difference. I was just wondering why you do not have it any lower? There is too low, but that is pretty low before it screws up the geometry.

[mohaughn]

The front right now is a 1/2" lower than the back. I could drop the front a lot more but the back is at the lowest point without switching to even smaller rear springs. I ended up not getting the shorty springs and I'm not running the height adjusters on the rear with the smallest spring pad I could get. If I were to drop the ass anymore I would definitely need to invest in the weld-in rear wheel adjustments as the rear camber doesn't need to get any worse.

Only having 17's makes it look like it still has a bit of wheel gap. The control arms are almost to the point of being vertical at the current height.

What's the height at the rocker panels on yours?

[AlaskaBlue]

Do you mean horizontal? I have 17s as well with uber rolled fenders to fit 235/40s on there. My car does have some rake to it. The rear probably has about 4-5 inches and the front is probably around 3. I could be off a tad, but I will measure next time I can.

[mohaughn]

For height I meant measuring from right behind the front tire and right in front of the rear tire... I'm at like a little over 5.5 in the front and a little over 6 in the rear. Do the KW's use a 4 or 5 inch rear springs? I think the ones I got were 6 inch rear springs and the shorter ones that you can get are 5 inch springs. If yours is lower in the rear with a height adjustable perch they have to be small springs.

If I were to take the front down another inch the control arms would be starting to slant down.

[kelso]

ran my first one recently as well, and between my first lap and my last one, shaved off 10 seconds from my time... i was running my 15's with continental tires though, no grip at all and lots of understeer
i might miss the february autocross but otherwise i plan on being very active this year

[mohaughn]

I've been wracking my head trying to figure out why the ass of my car seems a bit higher than other cars running coilovers and low profile tires... and I think I figured it out...

I don't have sideskirts.. On my 328i I measured that the side skirts were almost 3/8th's lower than the actual body of the car... I'm also running 215/45/17's where it seems like a lot of other people are running 2xx/40/17's..

The difference in diameter in a 45 vs 40 is .8 inches. So in terms of the distance between the hub and the ground it is .4 inches higher... Combined, the side skirts and the profile of the wheels add up to .775 inches... So I think my rear ride height is spot on at a little over 6 inches. Seems to match up with what other people have measured as 5.5 inches to the rear side panel at full drop. I could get the front as low as 4.75 inches on the current tires. Which would measure just a little under 4 inches with lower tires and side skirts.

I did go ahead and drop the front another 5/8th's to give it a little more rake. Nice to think I will get another .4 inches of drop all around by going with a 235/40/17 tire when the current ones give up the ghost.

[mohaughn]

Just picked up another cheap upgrade that will hopefully make me faster. Mainly because the shift knob won't be coming off in the middle of the course. I fumbled putting the car in second on my faster run last time when the knob decided to jump off the shift lever.

http://forums.bimmerforums.com/forum/showthread.php?t=685790

I was going to pick up an aluminum shifter knob from a vendor off of this site but I didn't want to have an extra heavy shift knob. This one is taller, more rounded in shape, won't transfer heat, and isn't as heavy. Only curious about how slippery it will be without gloves.

[AlaskaBlue]

I wouldn't think that it would be very slippery at all with some nice gloves. Definately seems nice. I'm glad someone else appreciates that a shorter knob isn't always good since you have to move your hand a lot further.

[AlaskaBlue]

http://www.318ti.org/gallery/data/500/medium/DSC000501.JPG

http://www.318ti.org/forum/attachment.php?attachmentid=3120&d=1169420880

I am still amazed at the height difference we have. I have a 95 too with no sideskirts. I mean there is a big difference. My front control arms are a few degrees away from throwing off the roll centers. The back is almost all the way down.

[mohaughn]

As it sits right now I have a little bit more I could drop the front. TcKline recommended 1/2 to 1 inch of rake maximum. My control arms are just a few degrees off of being parallel with the ground right now. If I put the fronts at full drop I would be well past the point where the control arms are putting down towards the center of the car.

TCkline does have a smaller rear spring, so I could get another 1.5 inches of drop on the rear with a smaller spring and 40 series tires. That would put it at a little over 4 inches on the rear. I'm not looking to slam it that much just yet. If I had to guess the KW3 rear spring is a 4 or 5 inch spring. You may also see some spring sag from the progressive rate springs.

Have you measured the height to your rear side panel? I've found a few other people that have coilovers set to the lowest point and they measure around 5.5 to 5.75 inches with side panels. That is with a HR coilover and another with a PSS9.

[S10mafia50]

The front rockerpanels on alaskablue's car are 3.75" right behind the wheel, and in front of the rear wheels, it is 5.5"

How do I know, I'm snowed in and it basically lives here....so I went out and measured with a tape measure....
Andrew

[AlaskaBlue]

I intend to get a hold of KW and run some shorter rear springs whenever the car is ready to be raced again. S10Mafia50 is posting measurements now.

[mohaughn]

OK. So the KW3s do give you more rear drop than the Tc/Koni DAs. I'll be at 5.75 or something like that with the smaller tire.

I actually had a question for them about my camber plates so I just called to ask about the other springs. Loaded the short spring will give you about 1 inch of drop. He didn't have the exact measurements on hand. If you are running the normal rear spring they recommend not using the height adjustable perch for the most drop. If you use the small spring they recommend using it. If not the spring will fall out anytime you jack the car up. Which can easily be fixed with some zip ties..

I have to go re-read the info about the roll centers on that e30 m3 website. I might be looking at my arms the wrong way. I could get the front that low but my arms would be pointing down by about 10 degrees or so.