Additional Camber & Wider Fronts

[nakkinator]

I've been taking my 02 Boxster S to the track and to Autocross, and it's got a few spots I'd like some advice in improving.

The car is on PSS9s with 225 RE71R up front and 255 RE71R in the rear. Current alignment is maxed camber front and rear, about -1.2 front and -2.2 rear, mild toe out front, mild toe in rear.

I've noticed the car is very harsh on the outsides of the tires, especially the front. That's getting better as I reduce over-driving, but a couple really hot laps will have a very noticeable effect on the tread shoulders.

1. Are GT3 LCAs really necessary for more camber or will camber plates get most of the way there?
2. Which wheel size and offset do I need to get a 255 or 245 on the front?
3. Are poly bushings recommended? My car keeps coming out of alignment, even without any wheel-cracking potholes

[thstone]

Originally Posted by nakkinator

Are GT3 LCAs really necessary for more camber or will camber plates get most of the way there?

Camber plates will add 1.0 to 1.5 deg of additional camber. This might be enough or it might not be enough. But it will certainly help and camber plates are a lot cheaper than adj LCA's.

But don't be surprised if you are right back in the same situation in the future because as you get better, then you'll be able to push the car harder and likely to need even more camber.

Camber plates are cheaper now but you still might need adj LCA's later. Adj LCA's are expensive now but you only have to do them once. Pick your poison.

Originally Posted by nakkinator

Which wheel size and offset do I need to get a 255 or 245 on the front?

Most of us running a 255 on the front simply use a stock rear wheel (17x8.5 et 48). You can safely run a 235 tire on a stock 17x7 wheel but that is about as wide as I would go on a 7in wheel.

In my experience, here are the handling characteristics at the limit of various width front tires;

205 Understeer
225 Slight understeer
235 Mostly balanced
245 Slight oversteer
255 Oversteer

Most of us running a square set up (255 on all four corners) re-balance the handling by using the 996 adj front sway bar and the Tarett adj rear sway bar to get the car back to neutral handling (or tuned to however you like it best).

[BrantyB]

I had same issue. I wanted to keep the car stock for autocross classing but there was no way the tires could make it through a season due to outer shoulder wear. It looked as though the car was utilizing about a third of the tires' width. I went to GT3 LCAs because camber plates cause all sorts of classing issues with PCA. The LCAs make a big difference and can give a wider range of camber settings. They are not cheap, but do make a big difference.

[Quadcammer]

just do the adj. LCAs and cry once. I tried to avoid it, but that lasted about half a season. Now I have the joy of fully adjustable caster and camber and its glorious (but a pain to set up).

As for 235s on 7in wheels. I just tried this with NT01s and its just too much tire for the rim. It fits, but there is significant bulge and I anticipate it not doing wonders for handling.

[nakkinator]

I was hoping everyone would persuade me to camber plates not LCAs! Crying for my wallet.

P.O. had put 235 all seasons on stock 7" width front and it was super squishy and pinched. The 225s look way better on 7", and I'd be increasing the wheel width to put 245 on there.

For the LCAs, I've read somewhere that it pushes your track width out. Is that for real? And will it affect the ability to stuff 245s+ under there?

[nakkinator]

Also, what's everyone's thoughts on poly or other stiffer bushings to help my alignment hold in the rear? Is there a favourite brand?

[maytag]

Originally Posted by nakkinator

I was hoping everyone would persuade me to camber plates not LCAs! Crying for my wallet.

P.O. had put 235 all seasons on stock 7" width front and it was super squishy and pinched. The 225s look way better on 7", and I'd be increasing the wheel width to put 245 on there.

For the LCAs, I've read somewhere that it pushes your track width out. Is that for real? And will it affect the ability to stuff 245s+ under there?

I'm not an expert on this, but I've been reading up too, cuz I'll be doing similar...

Yes, LCA's will widen the front track. But my understanding is that most guys are still getting a 255 in there to run square. (They're using 4 "back" wheels)



Sent from my SM-G930T using Tapatalk

[Topless]

Originally Posted by nakkinator

I've been taking my 02 Boxster S to the track and to Autocross, and it's got a few spots I'd like some advice in improving.

The car is on PSS9s with 225 RE71R up front and 255 RE71R in the rear. Current alignment is maxed camber front and rear, about -1.2 front and -2.2 rear, mild toe out front, mild toe in rear.

I've noticed the car is very harsh on the outsides of the tires, especially the front. That's getting better as I reduce over-driving, but a couple really hot laps will have a very noticeable effect on the tread shoulders.

1. Are GT3 LCAs really necessary for more camber or will camber plates get most of the way there?
2. Which wheel size and offset do I need to get a 255 or 245 on the front?
3. Are poly bushings recommended? My car keeps coming out of alignment, even without any wheel-cracking potholes

Are LCAs necessary? No
Will you get a much better setup on LCAs vs camber plates? Yes

Ask any pro setup shop that regularly puts cars on the podium and they will say "get the LCAs. Period.". Camber plates are a low cost alternative with partial results. Better than nothing but a significant compromise in setup.

255 square works fine on a 986 running OEM 8.5" wheels all around. AX veteran Carl V. Ran his 285 square with rolled fenders and careful attention to wheel offset. I think that was too much tire but... Carl is very quick.

I am not a fan of poly bushings on these cars. Stock fresh rubber works fine. If you are regularly losing alignment something is loose. Look around before it falls off. My front suspension loosened from my sub frame once and tire wear got ugly quick.

[seningen]

Originally Posted by Topless

Are LCAs necessary? No
Will you get a much better setup on LCAs vs camber plates? Yes

Ask any pro setup shop that regularly puts cars on the podium and they will say "get the LCAs. Period.". Camber plates are a low cost alternative with partial results. Better than nothing but a significant compromise in setup.

255 square works fine on a 986 running OEM 8.5" wheels all around. AX veteran Carl V. Ran his 285 square with rolled fenders and careful attention to wheel offset. I think that was too much tire but... Carl is very quick.

I am not a fan of poly bushings on these cars. Stock fresh rubber works fine. If you are regularly losing alignment something is loose. Look around before it falls off. My front suspension loosened from my sub frame once and tire wear got ugly quick.

If you want to go cheap -- and a bit one the chumpy side of things, you can go camber plates and redrilling the location of the mounting points.

Various opinions, but if you aren't going to be really adjusting those LCA's and just looking for a bit more camber -- this maybe an interim solution.

Mike