signal

I do not typically drive over 100mph, but I have been over 100mph (100-125mph or so) in at least two cars on a few occasions, my 2003 VW GTI and my 2000 996.

I have the full factory aero kit, and pilot sports with good meat on them. It seems that over 100mph the front end seems very floaty. Not sure if its just me and my inexperience at high speeds or what. I guess I was hoping the car would feel solid like on rails at 120mph, but its just nervous ground for me.

This would be on the Florida Turnpike aka Autobahn, during spirited runs where I couldnt see any cars in perfect light, and like I said, its only happened a few times.

Brian

Tippy

+1, I have an aero also.

1999Porsche911

Is the front lip installed on the front bumper?

99firehawk

check your tire condition and pressure

signal

Front lip is installed. Tires were just balanced, so I assumed pressure was good but will check.
I had new pilot sports in back, put 200 or so miles on them before testing at high speed.

Can someone describe what the car should feel like at 120mph? At what speed does it start to feel a little freaky to you?

Ray S

Put the M030 suspension on (mk I 996's) or x74 (mk II 996's). That will button it up.

1999Porsche911

What are you tires sizes, front and back?

signal

225 in front I beleive, 265 in the rear, 18"...........so I guess just regular 18" setup.

As for M030, would that really make a difference going straight at high speed as far as the floatyness feeling?

1999Porsche911

With same tire sizes as you and the same aerokit, without the front lip, I get floating above 120. With it, floating is gone.

Sids911

I have a C4S style front bumber + lower lip on my C2 (yeah, custom fit the bumper) - no floaty stuff. No other aero work (no side skirts, no fixed rear spoiler).

But I do recollect that on stock bumpers I was feeling a bit floaty on the front.

10 GT3

I noticed the front end would get light and wander on my 02' when I originally got it above 130 mph. Keep in mind that there were substantual changes that reduced the 02'+ front lift 25% and rear lift 40%. When I swapped to a ROW M030 suspension, it completely tightened up and I can say confidentally that it is extremely stable above 160 mph.

996 MBA CFA

Your tires are fine and so is your aerokit. I would be surprised if a front lip would make that big of a difference. Two questions - Is your car lowered? When did you do an alignment last on your front wheels?

StuartFirm

IMO, your suspension and front spoiler setup has everything to do with how the car feels at speed. I believe I would be a bit nervous driving at 130+ mph without the full aero kit plus front splitter and a lowered suspension. The base 996 will, of course, handle triple digit speeds quite easily, but the car's feel will be a little more . . . . shall we say . . . . light if you do not have the proper aero and suspension setup. And for good reason, as the volume of air entering the car at those speeds generates exponentially higher lift than at say, 70 mph. I'm sure there are many much more technical guys who can give you exact formulas using downforce, lift, volume of air, speed, etc.

Also, please note the crosswinds will have a tremendous effect on how the car feels at high speed. Since there is ordinarily more lift on the car at high speed, the crosswinds tend to have a greater effect on the car's straight line tracking thus highlighting the "light" feel of the car.

As for my 996 (see below for specs/mods), I feel well planted at up to around 160mph. I have had the car at an indicated 181 mph once and the car did begin to feel like I was getting a little light, but it was too tough to focus on any one thing at that speed. At 181 mph I ran out of straight road, but believe it would have finished the pull to a rev-limited 187 mph if I had more pavement. I routinely have the car to 140 -160 mph with no problems including shallow banked, broad cornering at 150 mph without much drama; however, if there are more than 5 - 10 mph crosswinds the car will dart around at 120+ mph and I will slow my butt down in a hurry. Crosswinds are not to be played with or taken lightly when performing high speed runs, not by me anyway. Crosswinds and stray puppy dogs are the enemy at high speeds. Come to think of it, at high speeds you have many more enemies, birds, stray tire treads from big trucks (a.k.a. alligators), nails, and the list goes on and on. You will notice I do not include other cars as an enemy because you should not be running those speeds in the U.S. with other cars present, since you never know what "grandma" or "the distracted driver" in the other vehicle is going to do next and the speed differential between you and the other cars is too great for relatively safe driving.

Tippy

I had a 1995 'vette Z07. That car felt 10 X's more stable at speeds than my 996. Once I was doing about 140 and you almost couldnt turn the steering wheel it had so much downforce. My 996's steering gets lighter at speeds over 100, I placed the blame on the wing, I wanted to take it off.

nick49

My '99 Cab feels great as fast as I've had it which has been at 155 with the hardtop on and my wife in the car. This was on a 2 lane country road in Kansas. I've been at 140-150 a few times with the soft top up and it always feels good, 140 top down feel really good, 125-130 one handed taking pic of the speedo and view thru the windshield, felt fine.

Over 20 years ago I raced a motorcycle at Bonneville Salt Flats and got wheel spin up to about 80 on the wet slippery salt and a few strong side wind gusts that try to blow you off course at speed. The long course is 5 miles of full throttle acceleration and a couple of miles for slowing down. My 2 way average was 148.546 and compared to my '85 ill-handling motorcycle on a soft slippery surface the Porsche feels wonderful.