I'll buy it on a front drive car, but not a McStrut rwd car.

 

+1

I know of only one RWD car where there's a significant number of people installing stiffer rear bars for Street class competition: the NC Mazda Miata.

As an aside, I'm not just speaking from theory or stuff I read on the internet. On my second Boxster I thought I'd try to address understeer by installing the M030 rear bar in combination with the stock (non-M030) front bar, effectively stiffening the rear end relative to the front. My car was still plenty pushy, and adding insult to injury, it was also floppy in transition. If I were to do it again, I'd install a stiffer front bar without hesitation.

I don't know if cretinx was suggesting removing your stiffer front bar and going back to the stock front bar, or actually removing your front bar altogether, but if the latter -- you might as well try it since it costs nothing but time, but I'd bet money on the resulting handling being disastrously bad.

 

I tried a GT3 rear bar for one day last year the car was loose. The back end liked to come around.

 

Like everyone said you'll have more fun with the Cayman if you can afford it. You'd have to do a lot to the 944/968 suspension to equal the out-of-box Cayman setup. Just max out your Cayman camber settings.

- A GT3 front swaybar is the correct way with your stock rear bar.

- As for SCCA classing, I strongly disagree with the Cayman 06-08 being in AS (street). They should have moved to BS (street) like all the other former AS (stock) cars.

 

They were; 05-08 Cayman is already in BS. It's the 2nd gen cars that are misclassed, 09-12 Boxster/Cayman is in AS vs C6 & C5Z06; and 09-12 Boxster S/Cayman S is in SS against the GT3, GTR, C7 Z06, etc. And NOT with the very similar first gens.

Write your letters! I wrote a letter last year requesting reclassing of 987.2S from SS to AS and 987.2 from AS to BS. Haven't seen a response yet (I heard a rumor they're still mutteling over what to do?), but if you can provide SAC specific information on just why you think that's the right move, it may help to get them properly classed.

 

When I started autocrossing my 964 it was in A-Stock, then B-Stock and now I run C-Stock......it was the most competitive from a classing point of view in A-Stock, until the S2000's showed up.

 

Believe me or not but people way faster than me or you have had success with removing bars to adjust balance.

In our cars stock or M030 front bar and adjustable rear bar is the way to go.

Unless you don't want to believe the professional race teams, engineers and physicists I've discussed this with or the people who have successfully put this into practice.

Doesn't matter to me.

 

Professional race teams aren't using stock springs and stock suspension adjustability. With our limitations, front adjustable GT3 bar is the way to go.

 

1. It'll matter to you when you drive a car set up as you're advocating and realize that it handles terribly.

2. As sjfehr pointed out, there are worlds of difference between how you set up a car on stock springs and a stock diff for autocross and how you set up a car with open spring rates and differentials for road racing.

3. You need to work on your name dropping; "I've discussed this with physicists" is pretty weak.

Here's a start:

Radomin Delgado, the only person to ever have won a Stock class jacket in a Cayman, says that "the car needs the 2010 GT3 front sway bar to be able to keep the inside rear tire on the ground". (He's GT on that thread.)

sl951, who said "a GT3 front swaybar is the correct way" a few posts above yours, was the highest placing Cayman driver in A Stock at the 2012 national championships.

And of course, a few of us on this very thread tried variations of the "softer front bar, stiffer rear bar" approach that you're suggesting and regretted it. While you should feel free to ignore all that and forge your own physicist-approved path here, everyone else would be much better served following the big front bar advice developed from many peoples' hard personal experience.

 

My 40th 996 is not a cayman, but i tried m030 front and rear, adjustable front with m030 rear, and m030 front with adjustable rear. The adjustables are GMG bars, similar to gt3.

I preferred the m030 front and adjustable rear. On fresh tires,
Inside wheelspin wasn't a problem, but I also have a (worn, stock) LSD. The turn in is great, but admittedly the car is loose and quite a handful.

 

Yeah -- I don't have any experience setting up 911s, but I'm guessing the fact that you have an LSD (even if worn, it's likely more effective than the Cayman's virtual LSD) is making the difference between switching to a bigger rear bar being terrible and just dicey.

Everyone's car, driving style, and typical courses differ, so no one should ever take someone else's word on setup as inarguable -- test stuff yourself. Having said that, pretty much everyone who's competed seriously in a Boxster or Cayman in Street / Stock has settled on a big front bar.

 

with these magical things called wheel and tire stagger, adjustable shocks, tire pressure, camber and toe you can take advantage of an adjustable rear bar without the car trying to kill you.

Do what you want.

 

...but don't remove the front bar.

 

I know we've drifted a bit from the OP's question, but since there seems to be a discussion here...

Is the GT3 front bar still going to give a noticeable improvement on an X73-equipped 981 Cayman? I'm not in the mood to make any changes, as I'm not running SCCA this year -- I'm running PCA, where bars can't be touched in Street Stock. Just wondering if it's been tried. Most of what I can find by searching seems to be folks upgrading non-X73 suspension with X73 and/or GT3 bars -- not so much putting a GT3 bar on a full X73.

 

This is true, for classes that permit those changes. For SCCA Street or PCA Stock classes those changes are not allowed or are very limited. SCCA Street allows for changing only one bar, no camber helpers, no spring changes and limited wheel sizes. With those constraints, a stiffer/adjustable front bar has been demonstrated to be the best option. Remove those constraints and sure, the formula changes.