Opinions on car's behavior

On my daily commute I take an onramp that has a right hand curve to to enter the freeway. The speed limit leading to the freeway entrance is 25mph, which I obey. The freeway has a 65mph limit which I like to reach right away. The entrance has a slight uphill grade. When I enter the freeway I am in 2nd gear and then give it full throttle. I notice that the car seems to oversteer as I come out of the curve and when I correct it gives a slight fish tail effect. Car is a '99 with 66K miles and fresh tires. Is this due to a driver problem? Suspension? Alignment? Balance? On my return I have the opposite on ramp entrance. This one has a slightly wider left hand curve and has a downward grade. I usually take it from a stop. I run to redline in first gear before shifting to second. This ramp has a very long approach which is one lane wide with concrete barriers on both sides. As before I do not exceed the posted speed limit entering the freeway. In this instance the car does not oversteer and behaves as I would expect. Any thoughts on why there is oversteer when going right but not when going left?

From what you tell us I lean toward driver error...the car isn't over steering, you are using too much throttle and the back end steps out as the road levels off. The fish tail is the normal response to over correction. If the tires were out of balance you would have vibration at certain speed. If it was alignment, you would notice when driving on a straight level street or under hard braking. If it was the suspension you would be noticing issues at other times and not just this one on ramp. Red line in first gear on a freeway onramp sounds a little unnecessarily aggressive.

I'm surprised you can break the tires loose in second gear. Are you still turning at this point? My 996 has so much grip with my Michelins that's I never have oversteer in any gear unless it's lift off oversteer in a turn (typically a no-no in general and especially a no-no in an early 911). I also have some understeer on on-ramps if I apply too much throttle while turning. Are you experiencing oversteer after shifting while in the turn?

Thanks gents! I'm going to safely experiment today with an eye toward driver error.

Remember that on plain old roads, there can be surface anomalies and/or substances (sand, oil, coolants etc...) that can wreak havoc on a car that's on the edge of breaking free (yours). Entering or exiting a freeway in this state can effect others bedsides yourself - be careful! - and only do this experimenting when there are no others around.

Yeah, I was going to say the same thing about experimentation. I would first study up and read about vehicle dynamics, the safety and performance of the racing line, how tires work, etc. Then, I would consider doing a driver education track event (HPDE) or autocross or somenofther driving school. Finally, if you do experiment after all these pre-requisite trainings, I wouldn't do it on these on/off ramps that have concrete walls and such on either side. The problem with most ramps is that there aren't flat and vacant stretches of land on either side of them, so mistakes could be very costly or even deadly (ask me how I know).

Thanks guys for the safety shares. I work in an inherently dangerous industry and take safety very seriously. I obey speed limits and do touch my phone or use hands free while driving. The greatest risk that I perceive is driving in traffic with all of the distracted operators on the road. For this reason I take routes that are less traveled. This particular on ramp is in an area with little traffic and I have full visibility of the road and any approaching cars from a great distance. I've driven 911s for well over a decade (including the occasional DE) and am used to this road. I've not experienced this type of behavior in my two older 911s. I'll post my findings.

Check the motor mounts too! Old mounts = "Water Sloshing in a bucket" feel from the rear end. The engine (roughly 450 lbs) shifting from one side to the other under power could easily cause your symptoms.

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Good tip. Supposedly you can look at the exhaust tips for sagging, but this does not always apply. They are easy to inspect

I drove this route only once today. I had no issues. Maybe the over steer came from me. I did look at the exhaust tips and the driver's side tip is 3/4 inch lower than the other side. What are folks using for replacement motor mounts? Do you need to change the transmission mount at the same time? Any thoughts on stock suspension after 18 years/66K miles?

I used these... Amazon Amazon They are OEM and the best price I could find. It is an easy DIY that takes less than an hour.

My vote is for worn rear shocks, especially if there is an expansion joint on the onramp. if they at 18 years old, they are likely to be less then factory effective. I experienced something very similar and had around 68k miles at the time. It was very noticeable on ramps that were less than completely smooth and bumpless. I agree with some other posts, it is very difficult at that speed to get the rear to step out at least with the Michelins. Even with very poor driving behaviour and worn rear shocks. This is not true of older spec 911's

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There are quite a few different types of motor mounts, each with pros and cons. The stock rubber mounts will have the most isolation from vibration and will eventually wear out again. Any solid motor mount will be transferring vibration to the car's chassis, but because they are solid, they can give the car a more raw feel and sound.

I didn't believe in the power of motor mounts until I had mine done (went oem since I had a myriad of other things that took $$). Fixed sag but more tightened the back end. Hard to describe but made the ride a lot better.

Every one of those "supercar idiot driver" videos on YouTube involves at least one person who powers way too far into a corner and winds up in a ditch, over a curb, or into someone's living room... I drive my car VERY aggressively whenever I can...and I apply full throttle almost never. 100% throttle off the line means wheel hop in a 996, which is not a pleasant sensation nor good for...anything; on public streets, there's nowhere I need to get to fast enough that requires spending any time with the throttle at 100%. Also, passengers puke less when you're not alternating between 100% throttle and threshold braking. You can easily push through 70MPH in second gear, and you say the ramp is posted at 25 - so you're probably at least doubling the recommended speed for that onramp. If you keep doing this, at some point you will find yourself at that spot where the back end twitches out...and there will also be a little bit of spilled oil, a puddle, or some accumulated sand, and then you will find yourself along for a very unpleasant ride. One of the worst n00b mistakes I made for far too long was smashing the throttle to 100%. It upsets the car, and it makes it impossible to throttle steer or effectively use any of the other weird driving dynamics the rear engine makes possible. Fast and precise on the throttle is better than just fast. It's also best to avoid drifting during your daily commute unless you're fast. And furious.

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These statements are incongruous. How does the same person who cares about obeying a 25 mph speed limit redline a 911 in 1st gear? There's no reason to ever redline these cars in 1st gear. Ever. Unnecessary strain on drivetrain components, and unnecessary risk for yourself and other users of the road. Even on a racetrack there'd be no reason to redline in 1st gear as there are no corners that are too slow for 2nd gear. Try a higher gear and take it easy. If you are losing control of ANY car while claiming to follow the speed limit on a dry road, you're doing something wrong.

It's also the case that many on-ramps are cambered to keep the car on the road. A speed that works fine on an on-camber curve may not be at all appropriate farther along that curve where there is little to no camber. Whatever the set of circumstances, the car is being pushed beyond its grip limits. The 996 may be a more tame 911, but it is still much snappier than a mid-engine or 50/50ish platform. Spending some time on a skidpad so you can get the feel of the car rotating at low speed will make you a lot more confident should it become necessary to try to save the car in a bad situation. Even if you fully understand the concept of opposite lock, being able to apply it in any manner that actually DECREASES your odds of dying is harder than you'd imagine at "normal" speeds. Just reading OP's description makes me uneasy...I do not think I would enjoy being in the passenger seat during OP's daily minidrift. There's a great YouTube video of brake failure on a long straight heading into a hard right-hander. The driver flicks the car into a heroic broadside drift, slides sideways off the track, plows sideways through the gravel trap, and stops perilously close to the wall...while the passenger screams "YOU SAVED IT, YOU MOTHERF****R!!!" I bring up that video only because it gives you an idea of how quick reactions need to be once you are in danger of becoming a passenger in the driver seat...and that's in a car that has not been optimized by many, many Germans to be as lethal as possible.

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Lets not get too upset about someone posting that they are driving legally on a forum. The last thing anyone needs is for someone to get themselves in trouble by "admitting" that they are breaking the law. Also, I don't think there's anything wrong with redlining these cars, or any high performance cars for that matter, in 1st gear, or 2nd gear, etc. Aren't these cars designed to do that? I have to floor every car I've ever owned. If I'm going to want to accelerate as fast as the car can accelerate, there's little choice but to use WOT and stay in the gear that allows for the highest horsepower under the [gear] curve, which in 911s is usually at or just below redline. There are times when I am making a right turn into moving traffic at 40mph, and the fastest way to get up to speed is to use a large amount of throttle in first, well into 6k RPM. One amazing thing about Porsche's is that they have excellent acceleration from starting at zero. I have no wheelspin in my relatively low torque (258ft-lbs) from my 3.4

I live life one on-ramp at a time. ps: I think James is having a little fun with the red headed stepchild forum

Hello everyone, Thanks to all for your feedback. I've concluded that there are likely three contributing factors to this behavior: 1) Failed drivers side engine mount. As Dporto points out this is the likely suspect. The sagging exhaust tip is typical of a failed mount. The age of the car and the hot and dry climate where this car has been for the past 15 years don't bode well for a liquid filled mount. This would also explain the unexpected and jarring creaking noise when I back out of my driveway and the driver's side wheel moves from the concrete pad to the asphalt that is a couple inches lower. When I bought the car I had a local dealer perform a multipoint inspection that included the engine mounts. While they were given a good bill of health, I do believe that they are a contributing factor. Pelican has a good DIY and I have changed the mounts on prior cars. Thanks to roguiethegiant for his comments. 2) Suspension. At 18 years the shock absorbers are surely worn. Thanks Sammaw for that suggestion. I think you are right. To test this I drove over a truly rough road and was not particularly impressed with how the suspension performed. 3) Operator. At 296 horse power and nominal 2910 lbs., the 996 is significantly more powerful than a 964 or 95' 993 with approximately 250 HP weighing in closer to 3000 lbs. This is surely a contributing factor, especially for an operator with not a lot of seat time in a particular car. For those who expressed concern about driving and safety, I would like to clarify that I stated that the roadway leading to the on ramp is posted at 25mph. I assure you that I obey that speed limit. The onramp itself does not have a posted speed limit. In most places it is normal to reach highway speeds as you enter the highway from the onramp. Driving 25mph onto a 65mph highway is not advisable, even if you have visually confirmed that there are no approaching vehicles. If I recall correctly the stock '99 996 redlines at 7200 RPM. The practical shift point is 6800 RPM which avoids range 1 overspeed's and the rpm limiter. I incorrectly referred to that as redline. 6800 RPM in 1st gear is 67mph in my car. While range 1 overspeed's don't damage the engine, the limiter certainly slows you down. I'm surprised that running to the practical 'redline' is considered overly aggressive. Do folks typically shift from first to second at lower RPMs? Where and how do they determine to shift? It's one thing in traffic when you don't want to make contact with the car in front, but in a wide open situation why would you not take advantage of 1st gear? This brings up another question. The dreaded IMS failure that supposedly plagues 2001 and later cars is often attributed to operators not 'properly' driving the car and thus somehow starving the IMS bearing of oil. Did I get this right? If so what to do? Fork out $3000 every 30K miles for a new clutch and bearing? Or drive the car? I promise I am not baiting anyone or having fun with the redheaded stepchild forum. Every p-car I have owned has at one point been considered the redheaded stepchild. I am just trying to learn as much as I can about my new daily driver. Thanks to all for their input. I do really appreciate the camaraderie.

^^ I think you meant that 6800 RPM in 2nd gear is 67 mph? Maximum speed in 1st might be closer to 35-40mph. I also shift my car a bit short, at about 7,000, because that last few bits of RPM don't seem to be gratifying. There's nothing more annoying to me than torque that falls flat on it's face before redline, and thankfully on my car, it's only the last 300 RPMs that do that, rather than nearly 1,000 RPMs in our other car (a 2.0t Audi).

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This is like the longest and most drawn-out way possible to brag about drifting on an on-ramp

Apologies for casting doubt on your intent OP. Whenever I'm driving the 996 at the limit it gives similar behavior to what you describe. But, honestly, it's hard to make the rear wheels lose traction. The mechanical grip seems to overwhelm the power even though it's not an underpowered car. You're just getting feedback that's consistent with the proximity to the car's threshold.

On ramps are a great way to stretch it out assuming the Hwy is not backed up! IMSB every 50K

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My thought is that you need to try autocross. Why experiment on public roads?

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That's kinda what I was getting at but I didn't seem to get any traction (haha). There's no circumstance where a 911 should be losing grip on a public road. And there's no need to redline these cars on a public road. In my opinion, at least.