alignment & new sway bars installed

[maniac]

I have a '02 996 C2, with H&R springs, HD Bilstein shocks and OEM 18 wheels.

I took my car to the alignment shop to install a front M030 bar 23.6 mm bar + a C4S 20.7 mm rear bar, after that I requested an alignment that will improve my handling both for DE track and street.

I ordered a copy of my prior alignment set up, and the new set up, and this is how it came:

FRONT:

Camber: -0.4 L & -0.9 R AFTER -1.1 L & -0.9 R

Caster: 7.0 L & 7.0 R AFTER 7.0 L & 7.1 R

Toe: 0.01 L & -0.09 R AFTER 0.04 L & 0.04 R

REAR:

Camber: -1.3 L & -1.9 R AFTER -2.0 L & -2.0 R

Toe: 0.26 L & 0.20 R AFTER 0.18 L & 0.17 R

Total Toe : 0.47 0.35

Thrust Angle: 0.03 0.00

What it was strange is that the template used was for a Porsche Carrera GT 04-06, instead of '02 996 C2.

Do you think my car will handle fine with the new sway bars and new alignment on my next DE event?

[ericinboca]

IMO and experiences....

Alignment settings depend on a lot of variables - the track configuration, the tire, your skill, ride height, stiffness, etc. The real way to determine proper track alignment is with tire temps if you are consistently turning hot laps and working the tires.

But, I think what they did is a very good place to start as a combination street and track alignment.

The extra negative camber will help keep the outside shoulders from wearing too fast; the slight toe-in in the rears will help keep the rear behind you where it belongs; and the toe-in in the front will keep the front end from wandering around on the straights.

Assuming this is one of your first DEs, go have fun, learn, and don't give the alignment a second thought.

Improved sways are a good choice for an upgrade, BTW.

[maniac]

IMO and experiences....

Alignment settings depend on a lot of variables - the track configuration, the tire, your skill, ride height, stiffness, etc. The real way to determine proper track alignment is with tire temps if you are consistently turning hot laps and working the tires.

But, I think what they did is a very good place to start as a combination street and track alignment.

The extra negative camber will help keep the outside shoulders from wearing too fast; the slight toe-in in the rears will help keep the rear behind you where it belongs; and the toe-in in the front will keep the front end from wandering around on the straights.

Assuming this is one of your first DEs, go have fun, learn, and don't give the alignment a second thought.

Improved sways are a good choice for an upgrade, BTW.

I think your comments are right. I did my first DE, prior to this new alignment, my car did well with Michellin pilot street tires (18 OEM wheels), after I found the right pressure 32 F & 36 R. Yes the rear tires where wear down on the right outside, I guess because most of the curves where left handed and several of the curves where close to 45 deg.

Thanks for your advice. ;)

[PAULSPEED]

Get some softer tires if you want to go fast. Yokohams

are fast but the rears wear out even faster. Try

some Goodrich. Set your sway bar for

the stiff settings on the track and set them on soft for

around town.

Paul

[perryinva]

His ARBs aren't adjustable. I didn't think a C4S (widebody) rear sway would fit a C2, as they have different part numbers...are you sure it fits fine? Any pics? Are those neg camber settings OK for street use or will they give excessive inside wear? Since your tires already have outside wear, those numbers are good, but what about with new tires, I wonder?

[lenobleb]

Hello,

That is a decent setup for a combo street / track use.

However, the problem with a set up like is that it is OK for both, but not great at either.

For the street you have too much camber and will wear the inside edge of the tires.

For the track you don't have enough camber and will wear the outside edge of the tires.

If you understand that and can deal with effects then your setup will be fine.

If you drive mostly on the street then you'll be buying tires more often than you like.

If you drive mostly on the track you won't get the performance you want.

If you do a mix of both the setup is OK.

Again, think about what you want.

Good luck,

Barry

[maniac]

Hello,

That is a decent setup for a combo street / track use.

However, the problem with a set up like is that it is OK for both, but not great at either.

For the street you have too much camber and will wear the inside edge of the tires.

For the track you don't have enough camber and will wear the outside edge of the tires.

If you understand that and can deal with effects then your setup will be fine.

If you drive mostly on the street then you'll be buying tires more often than you like.

If you drive mostly on the track you won't get the performance you want.

If you do a mix of both the setup is OK.

Again, think about what you want.

Good luck,

Barry

Thanks all for your advices!. I do more street drive, track driving is once per month or at two months.

[maniac]

Hi all,

Just came back from the alignment shop, they corrected the camber, but still my cars goes to the right, I was explained by them, that this couldn't be corrected, because of the outside wear of my front and back right tires.

Thinking of $, now that I'm hook to the DE. I just checked at bridgestone, for a Max Performance replacement tires for the rear and it goes for close to a thousand including mounting and insurance. Comparing slicks with the performance street tires, do they cost less?, will they last longer in the track?, can I use slicks only on the rear tires?, my car will keep the same height or it will lower more, that I need to see if it bottoms?, If my front tires are 225/40 ZR18 (18X8 wheels) & the rear are 285/30ZR18 (18X10 wheels), which will be the right size replacement in slicks?, what brand do you recommend?, tire pressure will be different than the street tires?. Sorry friends for all the questions, but I don't have any experience with slicks scratch_one-s_head.gif

[RFM]

A racing car needs 4 slick tyres (for racing purpose only) they are illegal for public roads, this said, a 996 stock (showroom) may not equipped with slicks according the manual.

[ericinboca]

Hi all,

Just came back from the alignment shop, they corrected the camber, but still my cars goes to the right, I was explained by them, that this couldn't be corrected, because of the outside wear of my front and back right tires.

Thinking of $, now that I'm hook to the DE. I just checked at bridgestone, for a Max Performance replacement tires for the rear and it goes for close to a thousand including mounting and insurance. Comparing slicks with the performance street tires, do they cost less?, will they last longer in the track?, can I use slicks only on the rear tires?, my car will keep the same height or it will lower more, that I need to see if it bottoms?, If my front tires are 225/40 ZR18 (18X8 wheels) & the rear are 285/30ZR18 (18X10 wheels), which will be the right size replacement in slicks?, what brand do you recommend?, tire pressure will be different than the street tires?. Sorry friends for all the questions, but I don't have any experience with slicks scratch_one-s_head.gif

Couple of semantics first just to be sure we are all talking about the same things. There are tires many people call slicks that are DOT legal R compounds. While they are legal to drive on the road, most only have two grooves to be DOT legal (and to satisfy some sanctioning body requirements that racers use DOT legal tires) and are not suitable for rain conditions. I've also heard them refered to as semi slicks, cheaters, R-compounds. Real race slicks have no grooves at all. The tires classified as competition/track on tire rack are DOT legal R compounds.

True race slicks and most R compounds not made for the rain, are not at all suitable in the wet. Liquids are not compressable like gasses, and you just ride right up on top of the water with no grooves and loose all contact. The two grooves in R compounds pretty much do nothing for wet.

And, as RFM notes, the manual says not to use slicks. Note, however, almost all the P cars I see at DEs use R compounds. I use an R compound on my track dedicated 986S. (And have a set of street tires on an extra set of wheels I use in the rain.)

Depending on the brand of R compound, you can probably get one for the same cost as a good street tire, but a slick is made of very soft rubber that, when hot, gives you more grip. So while the tire might cost the same, you will go through them much faster than street tires. Because of fast wear and the need to use them only when dry, you don't want these for everyday driving.

I tow my track car, but that's not practical for all. I have see many Porsches drive to the track towing small tire trailers - trailers specifically made to hold four track tires, and then then change them out when they get there. I've also seen some, who have short distances to drive to the track, show up with their R compounds already on.

I would not put slicks on the rear and streets on the front. The grip is going to be so different, you will have a lot of understeer.

On the size, the R compounds are sized the same way at street tires. Check 'em out on tire rack.

As for brands - everyone has their favorite. I use BF Goodrich G Force R-1s - they come as a stock size and are cheaper than some. The Michelin R compounds are very popular on the 996s I see. Hoosier enjoys the reputation for being the best - I don't know, never used them - wrong sizes for me. Kumho and Hankook are also popular and less expensive variations. Yokohama ADVAN R compound has some tread and I have seen a lotus run in the rain using those. I used them once - took a while for them to get hot.

For tire pressures, most makers of R compound will publish a hot pressure target range. I start many pounds below that range, and bleed after the first couple of sessions as necessary, and eventually get the right starting pressure to have the optimal hot pressure in a session.

I wouldn't be too quick to go to R compounds. You will learn more car control with street tires in the beginning. And the street tires can help you find the limits easier because they make noise - many R compounds do not squeal - they just let go when the limit is reached. When I go to a new track, I put on street tires to help me find the limits before swithcing over to R compounds.

Edited February 7, 2009 by ericinboca

[maniac]

Great advice Ericinboca. Thanks!! :thumbup: