Advice on suspension upgrades for mostly track use

2003 996 with 23K original miles on factory M030(US) suspension w/ stock alignment settings. Suspension is in good condition, no knocking or anything. I sold my track-only Lotus Elise earlier this year and bought the 996, have tracked the 996 4 times so far. So I am no stranger to the track (not trying to sound arrogant, I am an OK driver and always learning). Use of the car is 85% track, 15% street (8% of which is driving to/from the track). I have no need to ever daily drive the car. During my last 2 track events my instructors (different) have basically told me I am driving as fast around the track as my suspension will allow and both (unprompted) recommended I make some suspension upgrades. I am running R-compound tires on an extra set of dedicated track wheels. My budget is reasonable but I am not looking to blow the bank account (I used the Elephant Racing suspension builder tool and came to $12,000 eek!!!) So....my questions for those with experience: -What suspension upgrades should I make and in what order should I do them? -Is it pointless to install coilovers for track use without installing all poly suspension bushings or monoballs? (I mean even GT2/GT3 cars had alot of rubber in the suspension from the factory). If no what bushings should be upgraded and what can be left in rubber, if anything. Combo of monoballs and poly? (Mono's aren't cheap) -Should I do GT3/adjustable control arms or will just the eccentric adjustable inner control arm poly bushings get me where I want to be for camber? I am attracted to the cheaper option of the eccentrics. -Should I keep the stock M030 sway bars for awhile after the Coilover upgrade? Any help from those of you who have been down this road is greatly appreciated. I have spent the last few days reading thread after thread about these topics but they just leave my head spinning with conflicting info.

What should you do? It significantly depends on how much you want to spend, and where do you want to end up? I have an 02 996 that's a J-class PCA Club Racing car that I've run for 8 years. From a suspension standpoint, it has coil overs with stock suspension bushings, and just M030 sways, and only Tarett camber plates at the top of the front struts to get the camber necessary as the stock parts can't get enough; stock stuff does get enough camber in the rear for what I need. Is it going to be as good as the $12,000 option? No way, but it's fine for me and the amount I care to spend on this hobby! By the way, as you track more, these cars do really well with a limited slip rear differential, helps reduce tight corner wheel spin but REALLY helps braking stability.

Start with this thread. Lots of good information. https://rennlist.com/forums/996-foru...day-car-3.html

Since you have already the M030 sway bars why don't you contact Gert at Carnewal and check if he could put an X74 factory kit together for you. You will get a great spring + shocks combo ready for the track. I have been very pleased with his level of service and got an M030 RoW in 1 week from ordering to reception.

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Thanks your response is good knowing you can run at that level on stock bushings. I have no interest in the $12K setup I am thinking start w/ coilovers and alignment setup then go from there. Do you know what settings you are running? The car already has an LSD in it, installed by a previous owner but I have no records so I don't know what it is. When in a u-turn I can hear a gear like noise so I think it's a helical type.

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That's a consideration. You would not get corner balancing, ride height, or dampening ability. But the cost appears to be less vs coilovers and it would lower the car from my M030 US setup. From reading (and I could be wrong here) one can conclude that with non-coilover setups the front camber is limited by the tire hitting the spring perch which may not be an issue w/ narrower coilovers. Reading the M030 vs X74 vs. Coilover threads is enough to make your head spin.

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It helps high speed stability a lot to increase the rake of the car, which you can't do with M030/x74. There are some less expensive, but quality setups like FEAL Suspension which gets you stiff springs, simple adjustability, and ride height/corner balance abilities and camber adjustable top hats for $1500 or so. That's quite a deal!

I'm assuming you already have the brakes sorted out with track pads and either Motul 600 or Castro SRF fluid. As already stated, stock bushings and the M030 sways should be fine for now. GT3 lower control arms are good for adding camber but there are cheaper ways to accomplish that. Since it is virtually a dedicated track car you have the advantage of going with a track suspension. Don't bother with the X74, Kw v3 or Billstein PSS10. These are all good street/track setups but aren't aggressive enough for what you are looking for. I would go with a minimum spring setup of 600#F/800#R and maximum of 800#F/1000#R. So you will need the dampeners to be valved to match the springs. On the low end I like Feal because you can get into a properly sprung and valved race setup for around $1600. For middle range, MCS 2-way NR are a great setup from a great company and the latest spec for the SP996 class. Make sure that the front mounts that come with them include camber adjustment. Setup wise I would recommend a ride height of 4" front and ~4.5" rear. I've attached the drawings on where to measure this from. To accommodate this ride height, you will want adjustable rear toe arms and front and rear adjustable drop links. The only other item of note would be a race seat and harness if you don't have one yet. There is no way to brace yourself with the steering wheel and drive to 9/10ths of the cars capabilities at the same time.

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I agree I feel like the rake is backwards on the car...front seems even or higher than the rear on stock M030US. Feal Road Race 441 are the exact coilovers I am looking at. It seems you can't beat the price, especially w/ the top mounts, and everyone who has posted feedback on them seems to really like them.

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Yes I am running Hawk DTC pads and Castrol SRF fluid. GT3 brake ducts and the backing plates removed from all 4 rotors. +1 on the Feal coilovers. Thanks for the tips on ride height setup. For sure on the race seat and 6 points. I had that setup in my Lotus...My 996 has sport seats but I still have to brace w/ the steering wheel in hard corners....makes it tough to have "light hands" on the wheel as I should. Any recommendations on seats that I can still drive to/from the track in with "relative" comfort?? I am trying to get a set of GT3 seats as we speak but certainly would be open to other options especially cheaper ones (GT3's are $$$ even used).

having gone down the road that you are entering, I recommend a few things for you. My car was 90%track, but streetable and I did drive it on the street. I bought a set of used coilovers (RL) with camber plates..they are around, be patient.......installed GT3 sway bars with custom drop links......I did not do monoballs and pucks, as I did not want to create a race car suspension.....my car rode stiff on the street, but I enjoyed that..... I would also highly recommend you add GT3 brake ducts or, if you want to spend more, then add the cup ducts to get more air directed over the brakes....... I installed numeric racing shift cables and had GT3 seats with 6 point harnesses...this set-up was great for tracking and let me improve my skills tremendously, without breaking the bank..... I'd focus on safety, then track equipment....check your water pump (the vanes disintegrate and can cause "issues"), also I'd think about and AOS Motorsport version and an X51 oil sump pan/baffle set up.......this should serve you very well....... then you could think about aero, such as wings and splitters and canards...... Have a blast, it is a slippery slope but sooooo much fun! GL

The best track setups I've been in were kwv3 and ohlins. Blew me away really. but this is the 1st I hear of feal. Their prices are excellent when compared to kw and ohlin. Do they really compare?

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Everything I have read about Feal is very positive. The numbers seem to be good as far as spring rates and they are custom valved. Also having the camber top plates built in saves another $500-1000 off the cost of converting to coilovers which is another bonus. Plus they offer $75 per corner rebuilding for the original buyer when the time comes. My impression is they just have not added the "Porsche tax" on the pricing b/c their market in the past has been more on Japanese performance cars.

Recaro Profi SPG is a nice dual use seat. Not near as cool as the GT3 seats though. Stay away from the eBay Recaro fakes.

You appear to be using your car in an very similar manor to me. My car is not a race car and I want to maintain a factory look, including the interior while making improvements under the skin. Suspension Front LCA - 2 piece adjustable, I used Porsche, these come with rubber joints and rubber was what was fitted to early Cup cars. All of the other control arms are standard. - You could replace the tuning fork arm with an adjustable item which would allow you to adjust the caster , as the C2 runs a different upright/carrier than GT3 and you have to use the offset hole in the LCA to get it to work without the wheel rubbing the arch liner and subsequently there is no further adjustment. Rear LCA - 2 piece adjustable, again I used Porsche, however this time with a monoball, as per a cup car. Rear adjustable toe links, OEM All of the other arms I left as is, dog bones etc. - I gathered as much feedback as I could and did not see a justification for the spend. This winter I will be upgrading to the following., JRZ Cup Dampers Monoball top mounts M030 Front Sway, GT3 Rear Sway Adjustable drop links Fitting the cup dampers is a little bit of a challenge, particularly at the rear, hats off to Slakker for providing lots of info, although challenging from an engineering standpoint to ensure everything works the price I paid for them, including a rebuild and new springs would be in the same ball park as new PSS10 so I feel its worth the effort.

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Thanks for the info, especially about the front LCA and tuning fork arm relationship for camber setting. I had not thought about that. I am going w/ Feal coilovers which include monoball tops on both front and rear, the front one being camber adjustable. Spring rate is 7K/11K (390/616lbs). I looked at PSS10 but my feeling is they are way too soft for what I want, the spring rates are pretty low on those, I believe about 5K/9K (260/515lbs). In spreading out the cost I am thinking of just adjusting as much camber as I can w/ the monoball front spring plates for now, then doing LCA's later if I decide I need them. If I can hit 1.5-2 deg front and 2 deg rear I think I'll be in good shape w/ my current preferred track tires (RE-71r's). I will do front bump steer tie rods and adjustable rear toe control arms now too. Any idea if I can do the above w/o the top of the front wheel hitting the coilover?

It shouldn't be an issue. If so, just add some 7mm spacers on the front and problem solved. Ask Feal what it would take to go heavier on the spring rates. I was running 900#F/1000#R on a 2520lbs car. That was with no rubber in the suspension but I would think you would want to be at least 600#F and then rear to match (~800#).

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You don't think that would be too harsh at those rates? Seems pretty far above everything I have seen on the market for the 996. I do drive the car to/from the track.

In relation to LCA's you do not need 2-piece for the rear to obtain the camber you require, 2 is achievable on the eccentric bolt. Spring rates, Based on nothing but what I have read i will be going for 800 Front & 900 Rear with 150 Tenders all around. - My dampers will have a decent amount of adjustment but I feel spring rates are almost trial and error based on your specific requirements.

Today I was cleaning up the car from my last track weekend. So here are a couple photos of my left front tire after 3-1/2 track days. These are on RE-71r tires (R-compound) that I use only on the track (different wheels and tires for driving to/from the track). I assume my car is on stock alignment settings but I have never checked, but the suspension is stock. Looks like I need some more front camber eh?? (the left side of the photo is the outside of the tire) Both tracks I was on run clockwise so more LF tire wear.

^^^Following up to the above photo....So here is what I have ordered for my car so far: Feal Coilovers (7K/11K - includes monoball strut top mounts on both front/rear with front being camber adjustable, and includes sway bar drop links) Rennline adjustable rear toe links Rennline bump steer tie rod ends Powerflex "road series" kit polyurethane suspension bushings and subframe bushings (The road series kit is a mix of black (race) and purple (street sport) bushings. EPS "tuning fork" arms x4 with polyurethane bushings Soooo...my question is will I be able to get enough front negative camber with this setup? I'd be using the adjustable strut top mounts to get front camber. From what I have read it appears my front camber target should be -2 to -2.5 and my rear target should be -2. I have read alot over the past few days. GT3 arms would be my next step to get more front camber but before I spend the extra $$$ for those I am wondering if I can achieve my front camber with the stock setup and tilting the adjustable strut top mount inwards? I have also read some issues w/ maintaining suspension geometry on my C2 due to the front pickup points being unique compared to the C4, GT3, GT2 and Turbo cars. I might be reaching for someone to know the answer to this...I figure I'll install everything and try it...worst case I have to buy some GT3 arms and move the Powerflex bushings over to them to hit my target. As an aside I also bought a set of GT3 Euro seats, an Agency Power roll bar, and Schroth GT3 harnesses....oh and a 997 GT3 shifter too, just because! .

The RE-71s don't look horrible. I would probably flip them after another 3-4 days. As for camber, it will all depend on the top mounts for the front. But I would max them out and you should be fine. The GT3 arms will only get you like a little over a degree and when you get to that point you really need to be using a pyrometer to determine your camber effectiveness. Don't worry about geometry. The Turbo and C4 have worse geometry, the GT3 wheel carriers do not change the geometry. The GT3 control arms will help the geometry a bit but your are talking a 10th of a second. I still think your spring rates are too low. Was that the highest they offered? The BMW I traded for has 550/700# and it was fairly smooth driving 200 miles round trip to the track.

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The good thing about RE-71r's in my experience (on a different car FWIW) is they literally stick until they cord. On geometry I read that on the C2 you have to swap the GT3 arms left for right because in the normal orientation the wheel will rub on the front of the fenderwell...so you are moving the "figure 8" bolt hole in the outer bushing backwards instead of forwards. Spring rates...I have not asked Feal. I guess my reluctance is compared to what I see most people using on the 996 (Ohlins, PSS10, H&R) the rates at 7K and 11K are still quite a bit higher than those options.

Definitely reverse on the GT3 arms. I ended up going with adjustable thrust arm (crazy expensive tuning forks) to keep the fronts from rubbing and cutting out the fender liners. But I'm not sure all of the effort was worth it. Ya I think my KW V3 were 250/400#. They were great for dual purpose but street comfort is always going to cost you time on the track. You might ask Feal to valve the shocks to where you can up the spring rate without sending them back in. Are you doing the bushings yourself or are you having a shop do them? Some of them like the rear sub frame are very time intensive. Can't wait to hear how it goes on the track.

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I'm going to install everything myself. I am fortunate to have an extra garage I have setup as a shop with two lifts (a four post and a scissor lift), press, big compressor, etc. I've been a recreational mechanic for years and in addition to restoring a couple classic cars I did similar suspension upgrades on my prior Lotus. Once everything is installed I'll ballpark the alignment with a tape measure and take the car to a local speedshop for corner balance and alignment. I use to have my own alignment system but I sold it to free up some storage space. Thanks for the advice on needing the adjustable tuning forks... Hopefully I can hit my front camber goal with just the top plates.

Very cool. In that case you will have a blast. One last recommendation: https://lnengineering.com/996-torque...utomobile.html

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That will be very handy, thanks!

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^^worth is weight in gold!!! (well, not really but...) If you had to go to something like the Bentley manual every time you needed a torque value you'd waste hours over the course of a project!