savyboy

Like a bird, check 'yer perch!

A section of track I was running at Reno Fernley was a tad bumpy, CarreraGT claimed it was more like Baja. Upon nut and bolting my car before a track day this week I discovered the RR spring had come out of the upper perch and was a bit cockeyed. Also noticed I managed to get the tire to make contact with the upper/inner fenderwell! Yikes.

So after measuring the lower perch height I loosened it up and like a bad knee, popped the upper part of the spring back into place. Voila.

Anyhow, word to the track rats, give an eyeball to your spring mounts when giving the car the once over after tracking. Note of interest- at no time on this section of track did I feel out of control or that the tires were not in contact with the road. I dare say a testament to light wheels and PCCB.

Pics for your perverse pleasure:

DavidNR

Thank you. Will check!

stujelly

No offense but I have a serious question. I know you have done extensive work to your car after your, shall we say early to mid summer break from the track. I thought that you replaced suspension parts. Any chance this may have been an over sight when they put your car back together???

My point being I thought we were all buying an extremely high quality cars. Now its just that I find it hard to believe after we spent good money on these cars all these kinds of things like coolant line failures, rms oil leak, re-lube your CL wheel hubs, spring perch, etc, still occur.

I just want to drive my car and occasionally track it. Am I just being nieve, or lazy?

Carrera GT

You're absolutely right. A fully assembled strut can still end up being turned until it works out of the nylon upper block during ride-height and corner-balance work, especially when they're new and they're repeatedly at full droop. On the 993, the factory spec was so short, we'd put everything on zip-locs until the car was 100% stable!

I was told that Reno (as we drove it on the second day, recently) can be so violent in the bumps when driven in the (very) high speed configuration we chose ("4" I believe) that it will send heavy springs through the strut housing. I was short shifting and running wide to avoid the "Baha" line because I didn't want tires/wheels/springs/struts to endure the high speed compressions and because I didn't want to challenge the rebound to keep the tire in contact and prevent over-revs. I was even curious to go back and see peak rpm ... thankfully no codes.
For Savvy's hot rod, I'm guessing the frequency hit a "pitch" that walked the spring out of the upper block. It might have been "amplified" by the low stiction of the suspension upgrades, Tarret sways, Heim joints, wheels, ceramic rotors, etc. I doubt it, but it's certainly an advanced setup and it could be causing some unintended consequences where even PASM needs a tender spring.

Funnily enough, despite the 95 - 105 degree F ambient, I took an eyeball and flashlight excursion under my car just to be sure everything was kosher. Definitely a track that encourages you to run keeper springs! : )

savyboy

Certainly no offense taken! Knowledge is gained by all in the give and take my friend!

While it is *possible*, my tech is super meticulous and I doubt he let this get past him. I had eyes on the suspension during the rebuild as well and I surely would have noticed this even if he did not (I have a technical background). Additionally, the rubber ring the spring seats into looked to have had proper contact for a long while. And no weird wear where the spring was out of place.

So I think the rough section of this track worked the suspension to the point of
this resulting. Witness the tire contact in the fenderwell. I would be shocked if this happened on a smoother track. Don't misinterpret that I think this is a design flaw, I do not.

Pretty stiff preload on the springs when drooped out, I tried to rubber hammer it back in place with everything hanging and there was no way. I grew Popeye biceps in the process of backing off that bottom perch nut. So while possible, I very much doubt it was disturbed during corner balance. But we did do suspension work and it is possible this was somehow overlooked.

Unlike my friend CarreraGT, I welcomed this rough section of track so as to gain knowledge of my car under these conditions (call it wisdom vs. youthful exuberance ) and think it likely the spring popped out due to the violent nature of the suspension movement.

In any event, this post was simply intended a reminder of the importance of looking over your car very carefully if you drive it under challenging conditions. Cars 'n Coffee cars, and those of the "depreciate with no joy involved" bubblewrapping crowd need have no worries

Carrera GT

There's your problem. Popeye has forearms, not biceps. Eeee yuck, yuck, yuck.

http://www.youtube.com/watch?v=Ox5mzTtYfK0

mooty

some of us, like myself, just mumbles and bitches for sarcasm. but the CL greasing thing isn't that bad (yes, i dont like it, but i'll put up with it).

spring perch "sometimes" does the cockeye thing, not often. but it can happen.

rms oil leak isn't a major prob. just like the oil cooled/air cooled old 911's all SWEAT.

coolant line failure is scary, it happend to me and i spun off T9 at LS. but i have to say no other cars have been subjected to track abuse as much as 911s or GT3. as such, we do need to keep an eye on it and "pre-care" for them.

not saying any of it is acceptable but other cars got more issues. ZO6, great car mind you, needs tranny cooler, accusump, brake upgrades etc. STi's, i have not seen a stock or modified STi that i can drive an hour straight without overheating. blah blah....

i feel your pain, but as long as we all feel the pain ;-)

TRAKCAR

Stujelly; I'm with Mooty.
The cars are not perfect, but for a daily driver / track car it is the best one out there that can run low laptimes.
Anything else will need more $$ to last all day on track, or will break.
4K miles now, 11 hard track days, zero problems. Last '07GT3 17K miles, 50+ track days, zero problems.
I am not a Porsche guy and considered all cars before buying GT3 that I fit in and there just is no alternative for less money out of the box. Heavily modified Z06, M3, Mustang (Have one) will work, but you have to modify them. Cayman, Miata's, S2000 might work, but I can't fit in small 2 seaters and I don't want those cars for daly driving.

The GT3 charm is that they are fast and ready to go. Just add roll bar and seatbelts, but that is a US DOT thing, not a Porsche problem.

Thanks for posting Savy! Is Reno Fernley bumpier than Sebring?
I have not seen any springs go cockeye, but I will check. Learned something

If it happens on the track, is this something you can feel driving the car?

savyboy

Never been to Sebring, so cannot answer, sorry! Perhaps somebody in-the-know will share the knowledge.

I had no idea this had happened, and no clue by handling of the car. Presumably it would have jacked the preload a bit on that corner and predisposed it to oversteer in left hand turns, but I did not notice.

Agreed as well on the overall dependability of the 911 platform. Again, this post just meant as something else to check when eyeballing car.

Leigh2

I've driven Reno and no question it's bumpy! Especially on the back straight and some of the curbing could easily rip the sump off of any 911...but fun track to drive.
I think the 911 and the GT3 in particular are the most reliable track cars and best bang for the buck period. It's tough to go this fast for less $$$s and way too easy to spend tons more chasing an extra second or two..

mooty

aha u mean like u lol

Leigh2

yes like me But there are some people you just need to be in front of regardless of the cost

stujelly

Guys,

I appreciate all the feedback and comments. Quite honestly after I posted this I thought I might get brow beat. I love my porsche 11 gt3 rs and I just want to drive it.

These forums are so dang informative I have learned so much. More importantly, I value the opinions of my fellow gt3 ers.

But understand where I am coming from. I am as detailed oriented as the next porsche owner. Lets face it, that is probably what helped us get to the point to be able to buy these great cars.

But everytime I read one these new posts about check this and check that I feel like someone keeps adding to my "honey do" list and it puts me that much farther from getting back on the track again.

This last weekend I got on Buttonwillow all day, but I would not go out there until I got the cl lube thing taken care of.

Now its off to check the spring perches.

C ya around.

fc-racer

I started the thread about the coolant fittings because I had not heard about it before being an issue and had a close call with a concrete wall at our local track. I didn't start it to scare people from using these great cars as intended.

The fact is, I had 22+ track days on the car before the fitting gave way and it was on a very hot day too. While I'll only run water from now on in the cooling system, it should not detract from how amazing these cars are.

No car I've ever owned has allowed me to push it this hard around a track, lap after lap after lap, without having to give it even a second to catch its breath. This car is a beast, and a reliable one at that. Every track car has issues, this track car has the least issues of any I've owned thus far.

mooty

chk the perches and get up to infineon with us this friday