964RS_NGT

As in subject, what is the recomended minimum camber to use with 235/35 and 295/30, 19" 888's on a Carrera with -20 mm OEM sports suspension?

Thanks.

TAI2

Assuming you are putting these on a 997 DE car, I would go with -2.2 front and -1.9 rear.

tcouture

Can you get more than -2' camber with stock LCA's? I needed to replace front LCA's on mine to get there - but I have the regular C2S suspension.

T.

racer

http://toyotires.com/tire/pattern/proxes-r888 - set up and Care.. Toyo recommends between -2.5-5.0 degrees of negative camber

Toyo Tires recommends the following general set up guidelines for the Proxes R888:

From the website:

Operating Temperature: 160°F to 220°F
Hot Inflation Pressures: 32 to 38 (psi)
Camber: -2.5° to -5.0°
Caster: As much positive as possible

Most stock 996/997s won't get more than about -2 (and perhaps only -1.8) negative camber in the front without changing the LCA or adding camber plates.

Doc GTO

I run -2.5 in the front and -2.0 in the rear on my Toyo R888s. I also do have GT3 LCAs to get that.

TAI2

I have GT3 Cup LCA's and find -2.2 and -1.9 a good compromise for a DE/DD car.

mdrums

Like other have said Toyo recomends minimum of -2.5 degrees of camber. However I got away with -2 for a while. It depends on if you are tracking the car hard, your track and driving style.

Anything more than -1.3 can not be had on a Carrera S with Sport PASM. You will need the GT3 lower control arms.

I use -2.5 front and -2.2 rear for street/DE car.

Doc GTO

You upped the rear a little more? Didn't you use to run -1.8 or -1.9? I ran -1.8 at the last DE and it still was a little too much wear on the sidewall indicator. Seems like the -2.0 is the rears sweet spot.

mdrums

Yep...I was getting too much wear on the outside of the rear. It is now looking a lot better. I am carrying a lot more speed in the corners and was getting more outter wear and the rear was starting to step out on me too.

I decreased rear toe a little too...running .12 degree per side right now....down from .16 degrees per side....but have heard I should be running a lot more rear toe, like .20 per side for the track. Everyone has different opinions on rear toe.

cbzzoom

not an expert by a long shot but intuitively it seems to me that you want to minimize rear toe as much as possible, as long as the rear end doesn't become unstable. If you're getting too much oversteer, or rear end going loose under braking, then increase rear toe. If the car isn't unstable then keep the rear toe low.

I think GT3's need more rear toe than 997's because they generally oversteer more.

964RS_NGT

Thanks all for your input.

No LCA's are installed on this car. However, there are a used set of camber plates avaliable locally. They are said to fit with stock suspension. I'm sceptical but will have to find out.
Anyway, what improvement can realistically be expected from camber plates? An additional ½ deg neg?
If I end up at ~1.7 neg up fron, what is a good starting point for rear setting? You don't want more neg camber in the back, right?

Local tracks are quite slow but twisty, top speed at end of straights ~180-230 km/h. In current (stock) setup, street tires wear out quite quickley on outer sides.

mdrums

LCA's are really the only way to go on a 997 (Carrera S) car. Camber plates will not get the job done.

10 GT3

If you want to get decent grip and wire life out of them, 2.5 deg is the minimum. Less and you will get a lot of camber wear on the outside edge. Just monitor it and flip the tires to get more life out of them. These tires have extremely soft sidewalls, which is the main reason why they need more camber. They run best stretched on a rim (read and follow Toyo's recommendations). On my Carrera with 18x9/18x11 CCWs, I ran significantly faster(over 3 seconds quicker a lap) on 235/295 R888s than on 255/315 R888s. With the wide tires turn-in was terrible (due to tire flex) and they were very slow to heat up. I was also able to run about 6 psi less pressure cold on the narrower tires to get the same hot temps while significantly improving the response and feel.

Best way to improve camber is to get a pair of GT3 control arms and shim them out. I had 10mm shim packs on my Carrera to get -2.5 camber. To keep from having rubbing issues, run them RSR style: left arm on the right and right arm on the left with the track arms in the offset holes. The main benefit of the GT3 control arms over camber plates is the track gain which helps with stability and turn-in.

mdrums

Interest stuff...I've been running 245/40/18 and 305/35/18 R888's on my 9x18 and 12x18 CCW wheels for a few years. I wanted to try a lower profile size to try and lower the car and gear it down a little...just to see....so I installed 255/35/18 and 315/30/18 R888's. I only have 1 DE day on this size and noticed no real improvment in lap times but the track was a lot hotter and greasy so who knows....

I always thought the R888 to have a stiff side wall compared to RA1's or my street tires. I'm running 35/36 hot pressures. Anything near or over 38 hot with the R888's seems like less grip.

I only run R888's because I drive the car to and from the track. If I had a trailer I'd be on R6 or Yoko slicks....but this might be too sticky of a tire for my stock Sport PASM suspension.

RonCT

It's pretty much all been said. Were I to do it again, I'd still get the OEM Control Arms vs. trying either new or used camber plates. It's a proven product made by Porsche and it wouldn't be worth it to me to save a few hundred on a $100k car. My alignment:

-2.4 Front Camber
8.2 / 8.5 Caster
-0.2 Total Front Toe

-2.0 Rear Camber
.22 / .22 rear Toe

Even though we don't have adjustable height coil overs on our OEM SPASM suspensions, they did corner balance just to check and it was pretty much on the money.