13'GT Black

1. My rear slightly kicks out everytime when i gave it 1/4 throttle or more when making left or right turns. So most of the time i have to turn like a grandma in order to keep my rear from kicking out. The situation is worse when the road is wet, rear will drift side ways. Its even worse during u turns on wet roads, i have to give it less than a 1/4 throttle or rear will kick out easily.

2.When having fun on highway ill wot to 120mph and the car will feel floaty.

Do i need better tires or suspension upgrades? Im currently on stock tires and stock suspension other than whiteline phb.

Cruzinaround

Both the tires and the suspension need to be addressed. If this is a base GT then it's basically a stock touring suspension and the OEM All Season tires are not the stickiest, they are on the hard side so they will tend to break loose when you apply a spirited amount of throttle, especially when loading one side of the rear hitting the throttle into a turn. You can heat them up being in Florida they should get a bit stickier. But doing burnouts to heat them up is a bit.... over the top. And really shouldn't be what you need to remedy that problem.

Get some really decent summer tires. They will have better wet road gripping properties as well as superior grip on a dry tarmac.

The floaty feeling at high speeds is the soft stock suspension on the GT ( which still stands for Grand Touring BTW) You'll need better Springs, and better damping shocks... or a coilover setup or an airlift.

Then you can look into tweaks for the LRA (Live Rear Axle) and look into the various options for a Watts link setup to add a much more predictable stability to an otherwise antiquated rear.

How far you take it is really up to your budget and your goals. But, for a daily driver...
the order you should focus on is...

1. Tires = Summer High performance (do not cheap out here)
2. Suspension = Performance Springs & Shocks /Coilovers/ Airlift
3. Rear Axle Stability = Watts Link


BoOm
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PNYXPRESS

Tires and suspension aren't the problem here. Its standing on the throttle when turning a corner. it doesn't matter how much money you throw at suspension and tire upgrades. If you stomp on the throttle while turning with 400+ hp you will kick the rear end sideways.

As far as feeling floaty at high speeds, that is a body issue as the stock GT wasn't really designed aerodynamically to run that fast. I mean it was but it wasn't.(hence why the gt500 and boss cars receieved a splitter setup) Look into getting the BOSS 302 splitter or something equivalent. This will increase the downforce on the nose eliminating the floating feeling.

Cruzinaround

If the tire ain't stickin then they're slippin. That's the rule of thumb to go by. The biggest different I can say you WILL experience with the right set of tires is they will stick where they would previously slip. If I'm making a turn and I blip the throttle the last thing I need is the backend to kick out... and on the stock rubber that was more frequent than I cared for. With stickier summer tires....in warmer weather and softer dedicated winter tires to replace those crap all season Pirelli's... The tires just hook up. And the car goes where you point the wheel. Where previously it would wag the tailend like a fish. PNYXPRESS means well... but his opinion wouldn't work for me, I'm kinda thinking its the same for you OP. You can change your driving habits to accommodate an inferior tire setup, or you can buy a better tire. If you can afford it... get the tires. They are the most important upgrade you can make for ANY vehicle.

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PNYXPRESS

Yes tires will help to a point with normal driving, but no set of tires will grip and prevent "tail wag" in a slow 1st gear turn or u turn with a 400+hp car. Its all in your right foot. Even the Continental tire challenge guys know to ease into the throttle and not to just romp on it before they are completely straight coming out of a 1st gear corner or itll slide sideways, and they are running racing slicks with only 400hp.

Hell, my 100hp 4cyl fox will kick sideways if I romp on it while making a u-turn in first gear, especially in the rain

However a good set of summer tires will help once the car is straight.

13'GT Black

Im not even aggressive when im turning. Most of time it will kick out some with 1/4 throttle on dry pavement. U turn its even worse on wet road, i literally have to feather it or it will wheel hop. I do believe better tires will help but i think its just mustang/live axle characteristic. Im getting new tires soon, only 14k miles on oem.

As for the floaty question, i agreen with PNYEXPRESS these cars are not areodynamic and are not meant to go too fast. Some suspension upgrades suggested are abit overdone. Spring makes sense since it lowers car and eliminate some uplifing wind through underbody gap. I dont see shocks or coilover do much driving straight on track or highway.

Are you talking about front splitter? i seen some description on them mention nothing about better areodynamic. I think its just for aesthetics. What are some body mod i can do that actually worth getting and will noticeably help with areodynamic?

UPRSharad

Tires & Suspension. That's where it's at. Where in Florida are you located? Maybe we can meet up in person and you can take a ride in a properly set up car?

13'GT Black

Thats very nice of you, im in Fort Pierce.

SpartaPerformance

I agree somebody needs to drive this car to confirm there is a concern with the car and not the drivers left foot.

krazykevin

Springs and shocks actually help more than you think. Lowering springs are normally stiffer and prevent some of the floaty feeling. Performance shocks (Koni, ect...) make a huge difference though. The shocks have more damping effect and change the entire feel of the car at high speeds. I was very surprised at how much of a difference they do make and how much better the car feels.

Tires help too. A wider and stickier tire will make a noticeable difference.

You mentioned wheel-hop; if this bothers you I would suggest lower control arms and/or relocation brackets. The stiffer bushings in the LCA prevent deflection that causes wheel hop. Relocation brackets change the geometry of the rear suspension mounting points that also help prevent wheel hop and aid in traction (acceleration mainly)