Hi,
I'm a new member here and I'm looking for help/advise on track preparation of 2007 Cayman S.

Suspension.

1. Coilovers. I’m thinking about Moton club sport.

What would be best place (price and tech support) to look for them?

What spring rates are suggested? (I find standard car handling as understeering, generally speaking)

As far as I could see club sports are sold without upper mounts – what would you suggest?

2. I’m thinking about RSS lower control arms (GT3 type) for wider camber adjustment range.
Is there any experience with those?

3. What would you suggest for bump steer (if it’s an issue) on lowered car?

Brakes

1. I’m thinking about gyrodisc rotors – does seem as relatively inexpensive but worthy solution.
Opinions?

2. Pads – Pagid? (yellow or orange?)

3. Differential – I’m thinking about Guard TBD but one of the track that I visit often requires some cruel curb attacking and car does spend some time in the air (inside wheel) under acceleration out of the corner… I would love to go for clutch type but it is more expensive and requires maintenance (preload going off etc)
Any thoughts?

4. Oil starvation issues?

5. Reliable power steering failure solutions?
After reading this forum I tend tio think that switching to electrical steering pump (mounted in the trunk) might be the best way to go. Does anyone have more info/examples on this?

I understand that a lot has been written on above topics and I did search and read. But any fresh and informed opinions are welcome.

Also alignment suggestions. I will start with something around -3 front and -2 rear and work my way out of there.
What are your suggestions on toe?

Thank you and sorry for my English

Cheers
Ted

 

How much experience on the track do you have? If you're new to the hobby, you'll be just fine bone stock. The car is very capable right out of the box without any mods for an intermediate / advanced driver.

I'm an instructor here and the mods I've done are: brake pads, high temp brake fluid, track tires, Guard GT LSD, rollbar, Recaro SPG seats with 6 point Schroth harnesses, baffled oil pan, underdrive pulley.

Get the most seat time if you're new to the hobby and worry about the mods later (brake pads and track tires made the biggest difference).

 

Gene,
Thanks a lot for your suggestions and information.

I do have a bit of experience on track. Several years (6 or so) worked as racing instructor in various racing schools. Than I've been racing in Russian touring car championship (4 seasons) 2000-2004.
After that I was working in various positions (race engineer, tech. director, ceo) in professional race teams (mostly Formula 3 and some GT). Also race car designer (mainly chassis, suspension and aero - CFD)
Here's a couple of examples of my work:

Titanium alloy GT uprights


GT car rear subframe assembly


Formula car CFD study

Now I'm not saying that I'm fast myself but I do know a thing or two about how a car should be driven.

At this point I'm running a small racing school and design/preparation shop and I'm about to prep a Cayman that we'll share on track with my friend.

It is possible to learn about Cayman by myself but on this forum there's already lots of practical experience so it would be stupid not to learn from it. I think this is what the club/forum is about - sharing\gaining experience and knowledge.

Thank You
Ted

 

Thanks a lot for this info!

Baffled oil pan - as far as I understand this was in order to prevent/reduce oil starvation under high lateral g's. Did it cure the problem? Have you got an oil pressure sensor and log your pressure?
Would you recommend a source?

Underdrive pulley – to lower steering pump speed under high RPM? No more problems with steering pump?

Roll bar – what kind? Could you please point me to a good vendor/source.

Guard LSD – which angles did you choose? How long did you run it? Any wear? I mean did it feel any different with time? Did you measure preload (usually simplest way to check for wear without disassembling anything)

Brake fluid was changed even before first track outing in favor of motul 600

Thank You
Ted

 

Tudor,
It sounds like you have plenty of racing/driving experience:

"I do have a bit of experience on track. Several years (6 or so) worked as racing instructor in various racing schools. Than I've been racing in Russian touring car championship (4 seasons) 2000-2004.
After that I was working in various positions (race engineer, tech. director, ceo) in professional race teams (mostly Formula 3 and some GT). Also race car designer (mainly chassis, suspension and aero - CFD)"

I am sure you are already aware of this but to maximize your chassis, choose your tires, class legal weight and ride height first, and build your suspension/alignment around that. Also important is how you intend to run the car: sprint races or endurance. Most of the Spec Race cars here run coilovers with GT3 arms/Tarett sways. Underdrive pulley and baffled pan for reliability. Oil starvation is an issue with a 987 in high lateral Gs. Go to the Cayman Spec website for specifics and recent builds: http://www.caymanspec.com/

 

Many thanks Cajundaddy,
This car is NOT going to participate in races. Track days only (May be time atack at max). This is friends car and at this point he's not going to get into competition. He asked me to make the car the way I would do it for myself (with his intentions in mind) for maximum entertainment/driving pleasure. I'm going to do the work for him (choosing components, installing and set up) and in return I will be able to drive on track from time to time - just for fun of it.
So this gives us some freedom.
Reading this board and also planet9 I got an impression that underdrive pulley in some cases wasn't enough to prevent PS lines melting and fluid loss?

On the ARB's - I'm planning to fabricate blade type bars for him. To me it's the only type of ARB that is worth it. Not knowing which exactly rates will work best on this car I'm planning to choose torque tube OD/ID and blade geometry so that at softest blade position bar is close to standard and at siffest position roughly + 100%. This way we'll be able to find what works best and also be able to very quickly go for soft settings in case of rain and slippery conditions.

Something along this lines:


Thank You
Ted

 

Gene (EL GT2),
I tryed to respond to your PM but I don't have enough posts yet (must have more than 5)

Thank You
Ted

 

Good info Ted,
Stay focused on your drivers goals, track experience, tire choice, and target weight, and you will develop an ideal track weapon for him. The build for a weekend warrior with limited experience is necessarily very different than the build for a seasoned driver at the top of his game. A totally tied down car with the finest suspension components will be very precise AND very unforgiving. A pro driver will learn to use all of this car and turn very fast laps. A less experienced driver may find such a car very twitchy and frustrating to drive. He will be just as likely to put it in the weeds as turn fast, consistent laps. Build to the driver and continue to develop the car as driver experience and ability grows over time.

Good luck with your build and be sure to share pics with us as your car gets transformed.

 

Thanks a lot, Cajundaddy

Good Luck
Ted

 

Hey Ted, nice work on those parts.

Regarding oil starvation, some owners of 2006-2008 Caymans who tracked their cars have had engine failures. It reportedly is caused by oil starvation during hard left-hand turns, especially with sticky tires. Oil collects in parts of the engine and doesn't return to the sump fast enough, so baffles don't fix it. The TTP Oil Safe system is supposed to correct the problem with scavenge pumps and additional plumbing.

Cheers,

 

Many thanks for your suggestion Jeff. I'm already looking into TTP solution. Best way will be to dry sump it but it's out of budjet of this project.


Pete,
Don't know if your read this.
I got your PM, but I'm up to my eye ***** with some work atm. I will reply very soon (I hope )

Thank You
Ted

 

Recently I'm going through a build that pretty much includes all the answers you are looking for. I can post some thought in about 1 months or so when I have some track time with it.

 

WWJD,
Thanks, I would be very interested to hear your thought and findings.

Thank You
Ted

 

Ted,

Understood. I will have a post up in a week or so in regards to my Boxster Spyder set-up and development. Pretty involved project going on here. Some of it will be applicable to your project. Latest testing resulted in transformation of handling on track (of an already great car). And a reinforced opinion that the "conventional wisdom" is frequently stale and wrong. Some teaser pics while part way through the upgrades:

 

Pete,
I see that you went with tarret stuff. Does that thrust arm bushing allow for castor adjustment? I already ordered RSS lower arms they are more expensive than GT3 arms but justifiable because they are better parts - CNCed from billet vs cast factory + stiffer ball joints + replacable outer balljoint unlike the factory where one has to buy a new part. As chassis engineer I will assure that it is one of the most loaded joint in all suspension. Even slight play in it will hinder handling. Also RSS allows for RC height udjustment.
I ordered Motons (got a good deal - 200$ less than list price) and TBD from Matt.

At this point I'm looking for suitable electic steering pump. Thats what we always used on racing cars (touring and GT). We'll place in the trunk. Apart from better reliability it will aslo safe few ponys.

At the start we'll go with softer springs (450 - 600/550) and ARB's on soft side and will go for more responsive (stiff) setup as he will develop as a driver (as Cajundaddy mentioned) Balance - we'll start with front roll stifness about 60% (taking in consideration springs, bars and geometric forces) which is very conservative.
I got suspension coordinates (in .gem format) from fellow forum member and will look into it later. Will be interesting to see what actually happens with Cayman suspension geometry during dynamic events - Mitchell Software allows to import logged suspension data and it will show exact positions of every suspension element relative to chassis/road on every meter of the track.
Thats how ARB's will be designed for this car - get on track data, suspension cad data. Get it into simulation (like LapSim or up to Vi-grade (ADAMS)) see what range of parameters are predicted to work. Design a part that allows enough adjustability that will cover desired performance window - > test -> on track data -> design updates - final part. Titanium alloy blades, sealed ball joints (car will see some street) etc.
There are some engineering toys left form racing days. So will put it to work
I always loved to design and test ARB's - in formula car it's usually an extremely restricted space so I preferred T-type bars. If it is of interest I can up some pics.

You where mentioning tarret blade type ARB's and fit of front bars/links. I'd love to know more about it or we can use email if you don't like to make it a public discussion. I can't send PM's yet - need some more posts.

Thank You
Ted