2007 Lotus Exige S

[asshanson]

All new star specs with less than 500 miles on them. Don't really want to mess with shocks or springs yet, they are all stock.

They were all tight turns, like 20mph or so.

[simulatedwood]

Did the front of the car feel like it was digging at all or just sliding? How does the tire wear look for a new set of tires?

[asshanson]

It wasn't too bad, felt alright but the front just doesn't have as much grip as the rear. Definitely wasn't sliding all over the place. Maybe I'm just comparing it to the corvette which seemed really neutral, if I gave it a little gas the back would come out just a bit. It seemed to have the opposite effect in this car, more throttle just made it push a little more, maybe I just need more throttle haha. I haven't checked the inside/outside tire wear yet.

[BriK]

All new star specs with less than 500 miles on them. Don't really want to mess with shocks or springs yet, they are all stock.

They were all tight turns, like 20mph or so.

The newness of your tires could be a factor. You may know this already but, generally, it takes about 500 miles to wear off the mold release lubricant which hurts traction; that 500 miles is usually for easy, casual driving so you might be through that already. Also, full depth tires will squirm a bit more than worn tires due to the taller, more pliable tread blocks. It's subtle and Star Specs should squirm less than "normal" passenger tires, but it could also be a factor.

With this, and knowing Star Specs especially improve as they wear, personally, I'd give it some time before changing too much. Maybe play with tire pressures-- overall and the balance from front to back-- and see what that does.

The "nice" thing about understeer is that, to correct it, you just do less of what's causing it-- less steering input, less brake, etc. If it's happening under acceleration, try squeezing the throttle gradually as you unwind the steering wheel so you're unloading the front tires a bit more gradually.

I hope I'm not being too basic and saying things you already know, just trying to offer my thoughts.

[simulatedwood]

It wasn't too bad, felt alright but the front just doesn't have as much grip as the rear. Definitely wasn't sliding all over the place. Maybe I'm just comparing it to the corvette which seemed really neutral, if I gave it a little gas the back would come out just a bit. It seemed to have the opposite effect in this car, more throttle just made it push a little more, maybe I just need more throttle haha. I haven't checked the inside/outside tire wear yet.


Yeah, if the wear is on the more outside edge, I could see adding camber helping alittle bit. Pay attention to the motion of the car in a low speed situation, you might need to trail brake to keep more weight over the front wheels on lower speed turns. Be careful, Since this is a mid engine car the likely-hood of swapping ends can be high if to much weight is transferred to the front.

[asshanson]

I hope I'm not being too basic and saying things you already know, just trying to offer my thoughts.

Not at all, I have very little experience and everything helps. I actually forgot to check my tire pressures ahead of time so that could completely fix the issue. Terrible n00b mistake, I know.

Yeah, if the wear is on the more outside edge, I could see adding camber helping alittle bit. Pay attention to the motion of the car in a low speed situation, you might need to trail brake to keep more weight over the front wheels on lower speed turns. Be careful, Since this is a mid engine car the likely-hood of swapping ends can be high if to much weight is transferred to the front.

I found this out the fun way. Braked a little too late for a 180* turn and also downshifted late since I couldn't get it into 2nd, and as I enter the turn and 2nd engages I do a quick end-swap. That was on my 3rd run of the day. It was close a few other times but some throttle quickly planted the car again, that was a blast.

Thanks a lot for the help guys, hopefully I can do another event or two before Proving Grounds to get these little things worked out.

[asshanson]

I started the toe link install tonight, I bought a kit from the shop that tuned my car. It's the cheapest, lightest, and strongest available but it requires drilling out the OEM holes for larger studs. The OEM ones are very prone to failure and I'm surprised the car didn't have aftermarket already since it was a track car.

Since I had the car jacked up I checked the front camber and there was one shim still installed. Previous camber was -1.85 and each shim is good for -.25*, so it will be around -2.1 now. Also I discovered the rear toe was 6mm (in) and should be just 3mm, so I will have that corrected when I get my alignment after the toe link install is complete. Also going to do 2mm total toe out on the front for better turn in and front grip. All these specs are what I have read online and also what my tuner suggested.

There are also a few shims in the rear but they are already at -1.6* camber, the inner nubs on the tires have worn down but the outer are still fully intact, which tells me I don't need any more rear camber (I think). Tire wear is almost dead even inside and outside on both the front and rear tires, but at only 500 highway miles and 16 track miles it's too early to tell I think.

The nubs on the front are worn both inside and outside, maybe need a little more tire pressure to keep them from rolling.

Thoughts?

[asshanson]

Got the rear toe links installed, first bought a cheap chinese cobalt bit and broke it immediately, then got a quality high speed steel bit and everything went super smooth. Stock holes were around .31", I drilled them out to about .44", so not a lot but enough for the bigger toe link bolt to go through.

Stock vs aftermarket, you can see the larger diameter bolt on the new one:
http://www.dsmstyle.com/photopost/data/675/toe_links.jpg

Stock installed:
http://www.dsmstyle.com/photopost/data/675/stock_toe_link.jpg

New one installed:
http://www.dsmstyle.com/photopost/data/675/toe_link_installed.jpg

How it looks from under the car, the bolt also holds in the lower A arm:
http://www.dsmstyle.com/photopost/data/675/inner_toe_link.jpg

Rear wheel steering engaged, also liking the front camber:
http://www.dsmstyle.com/photopost/data/675/rear_wheel_steering.jpg

Also I removed one camber shim from the fronts, and two shims from the rears, hope to get an alignment Sunday or Monday. But it should be a little over -2* camber on each wheel.

[asshanson]

Thought I would explain this pic, because I love learning about different suspension setups and maybe somebody else does too. Every one of my cars has been quite different (well I don't know anything about the V), but this one is especially different.

There are upper and lower A arms, and the upper connects via a ball type joint to a block which bolts to the hub. In order to adjust camber you add or remove shims between the A-arm block and hub. Unfortunately those are 8mm allen heads which suck, but I thought it was a cool design. I always thought the lop sided bolt/holes to adjust things were weird and would rotate in time, but I am just a suspension noob.

Front camber is normally limited to -1* if you remove all the shims. Apparently the previous owner milled down the A-arm block about 4mm because it is well over the stock adjustability at this point (little more than -2). BECAUSE RACECAR.

http://www.dsmstyle.com/photopost/data/675/camber_notes.jpg

[scheides]

leave them sideways like that then light smoke bombs and zip tie to chassis...epic king-o-drift! But you only turn left.