Paul 996

Recently I completed the install of a take of 2004 GT3 suspension into my 1999 C2 Aero. All the parts fit right in and don't require changing the wheel carriers, etc. These bolt into our cars just like the ROW M030 does, bolt for bolt.

My car came factory with the US M030 suspension and while that was a nice upgrade from stock after 1 year of playing on the track I wanted a tighter suspension that would provide higher handling limits on the track, but still wanted a streetable daily driver type of car. Also, I wanted the suspension to allow me to align the car and balance it as I deemed necessary.

I test rode in cars with the PSS9s: too soft, X73: more like it, JIC: even better but didn't seem to handle corner transitions and bumps well (my observation as well as the owners) and then JRZs: sweet, perfect but way more than I wanted to spend. Never got to try Motons which I am sure are great.

Overall I am really happy with the results, both from a handling stand point and how the car looks (low). Also, I like the GT3 Bilsteins because if you later want to go to stiffer springs you can simply send them into Bilstein USA and have them revalved to match the new spring rates.

First pic: the GT3 Suspension.



A side by side of the GT3 rear assembly next to the US M030 rear. The GT3 units are much shorter.



Front shot of my car on the alignment rack. Lots of negative camber.



Rear shot on the alignment rack.. guess I can definitely fit wider wheels with more aggressive offsets.



The car profile on US M030, slightly lower than US stock but not much.






Initial alignment settings are set to
F: -2.7 Camber, 0 Toe, Stock GT3 Ride height
R: -2.5 Camber, 4mm total Toe In, Stock GT3 ride height

GT3 front and rear sway bars are set to 1 from full Hard, for now.


And Finally the After shots. Tried to match them up the stock shots as much as possible

TheSpeedDemon

Oh yes, much better appearance and more handling too...I like it

blinkwatt

Are those H & R springs standard on GT3 set ups or where those added?

I have to ask because my Dad wants the same exact set up,how much?

Gator911

Is the OEM GT3 suspension height adjustable? Looks to be?

Where did you pick this up at BTW?

Paul 996

everything thing that I used came stock on the GT3. So yes, GT3 and GT2s use H&R springs. The GT3 suspension is height adjustable since the lower spring perch is threaded (just like PSS9s, JRZ, etc). FWIW from the pics of the 4 GT3 shocks you can see that there is still almost 1" left to lower it if you were so inclined. I did it for the handling so decided to leave it at the stock GT3 ride height based on feedback on the GT3 forum.

I bought these used from another member who upgraded his GT3. Sway bars came from Brandywine and the drop links were sourced from another member on this board.

redridge

very nice, give us some driving impressions, street and track. TIA

Ubermensch

And a comparison to the x73 setup you mentioned that you had tried...

Paul 996

Well suspension feel is very subjective. To me a firm chassis that communicates what is going on between the tire and the road is ideal. I didn't want a plush ride, softer than stock, etc. I wanted what would work better on the track. The GT3 uses much stiffer springs than stock 228 F/573 R and the shocks themselves have very aggressive valving. Some have said the the GT3 shocks are over dampened relative to the springs that they come with. I did not test them on a shock dyno so I can't say. The rear end feels significantly more planted and stiff. Overall it is not harsh to drive on the street at all and I have no regrets in how streetable it is. IMHO this should have been the Sport Suspension option from the factory.

I don't really want to give too much driving impressions based on street driving. I'll be at the track this coming weekend and will post impressions after that.

On the street they feel very good. The car is very crisp on turn in and stays perfectly flat. Right now at the limit (much higher than before and than I really care to explore too much on the street) the car exhibits some understeer. I plan to fine tune the balance on the front and rear sway bar to get this where I like at the track.

I don't want to mistate my experience with the other suspensions...I did not have them installed on my car and my comment was based on my impressions from driving or riding with someone during a track session. My impressions are that the stock GT3 setup (and sway bars) is slightly better for track use than the PSS9 or X73. It is at least equal to if not better than the JIC/Cross but not at the level of the JRZs, Motons, etc.

Benjamin Choi

You need some spacers or aftermarket wheels with more aggressive offsets.

And I'd rather run PSS9s or the X73s than the GT3 suspension on a non-GT3 car. Your car doesn't have the chassis, engine, tranny, nor brakes of the GT3.

Regardless, thx for sharing.

perfectlap

interesting observations and great job. Are you considering lighter wheels? I think your current wheels at 18" are closer to 30 pounds than the Carrera 5 spokes. Shaving 10 pounds of moving weight at each corner will enhance your current set up all the more.
p.s.
if you call Tower Paint and provide them with the paint code they will send you a color match in a decent aerosol spray can that you can use to touch up the stoning on the front of your skirting.

Ranger

Very interesting, and a very thorough post. Can I ask what you paid for the take-off GT3 gear?

Paul 996

perfectlap

Will absolutely be looking for lighter, wider wheels with considerably more aggressive offsets but for the track not street.

Thanks a ton for the tip on Tower Paint. Will definitely follow up on that.

Paul 996

Ben,

I guess I couldn't expect much more from you than your usual mis informed, over opinionated and cocky responses.

FYI: would love to know what you are basing your statement about the lack of suitability of the C2 chassis for a stiffer suspension like the GT3s. Is it that no one races a 996 based C2 in Grand Am or Koni Challenge using Cup Car suspensions, Motons, etc? I assume they all throw away their brakes, transmissions and engines as well.

I do state in my post that with the aggressive camber the car could use wider wheels with a more aggressive offset, but I'll likely do this purely for track use in order to fit more rubber as opposed to a cool blingy street look.

There ya go.

Paul 996

Ranger, sent you a PM with the info. Thanks. -Paul

KJinDC

Paul,

Hopefully my car will be ready and I'll be at the DE this weekend. I'd like ot get a ride in your car to see how it feels.

-KJ