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Discussion Starter #1
My car lost control again. I wasn't even speeding!

I was going over a large open slight grade hill, wide lane at about 60 and my back tires slid out from behind me, went to correct it, and started to lose more control, spent a good time trying to recover, and ended up off the road. Could have been horrible. What gets me is, it wasn't a stupid mistake, it was normal driving, and my CAR lost it. Thankfully, I knew how to keep it on the road tell it was safe speed to get off.

What gets me is, I was barely speeding! and the quality and turn/hill of the road is something that could have been on the freeway.

I'm pretty shooken up, but my car continues to do this slip thing in the back!

What do I need to improve traction?

Right now I have new front suspension, should I drop it to shelby specs? (shelby mod?)
I have new rear leaf springs, and I'm running:

245/60/14 TigerPaw tires in the back (crap!)
225/60/14 Michelin Pilots in the front

Do I need the TCP subframe kit?
I have a MonteCarlo bar I'll put on today...

What else can I do?

Should I get rid of the car and get a better handling car?
 

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You have about 2.5 times the power that ford designed the suspension to handle. You have a car with about 60% of the weight on the front end and you describe your rear tires as crap. No wonder you have a problem with breaking the rear end loose. You need to concentrate on things that will make the rearend stick to the pavement. Since you have new rear springs, the other things are the tires and the shocks are candidates for upgrade. Here is an article about improving traction for a 5.0, but the basic principles apply to classics. http://mr5oh.tripod.com/traction101.html
 

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Based on the situation you describe the problem would seem to indicate shocks. It is the job og the shocks to keep the tires in contact with the road. Had you been going around a corner then sway bars would help. The shelby drop would also help in the corners. You need a set of spring compressors, other than that its basically free. You'll need an alignment after your done.
 

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Are you sure the entire suspension is replaced and no fasteners have come loose?

I had a sloppy steering box, a bad idler arm, nasty shocks, and worn out strut rod bushings on my car......scary business!!!! The car would steer wherever it wanted to on bumps and braking hard!!
 

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Well this is actually an easy one. I was alive when the change from bias by to radial occurred. Different radial tires track at different rates. To make a long story short, many moons ago the tire mfg's use to publish a document that would give different tire mfg's mixed with other mfg's tires and state whose should be on the front & rear. Gueass what, the Michelins always out-tracked the Uniroyal Tiger Paws, meaning, Michelin goes on the rear, Uniroyals on the front. It will still be a squirly combo, but not near what you have now, shame they aren't the same size, then you could rotate.
 
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Get a new set of matched tires and replace your rear shocks BEFORE we read about you in the Obits. Do it! NOW!
Squirly handling sucks.

JB
 

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Discussion Starter #9
Well, I got Koni Classic's, tightened up pretty good.

Ya, I'm going to work on subframe and new wheels/tires!
 

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I would:

First: Get the car to a mustang pal who knows suspensions. Make sure that your is in good working condition and not worn out, loose, or somehow botched by POs.

Second (if #1 is OK): Consider upgrading your shocks, springs, tire/wheel combo. Add subframe connectors, MC bar, export brace, etc.

Third: Consider alum heads to drop your front end weight.

One last thought - do you have front disc brakes? If so, is your proportioning valve properly adjusted? I was thinking that if your front brakes engaged first (and hard) going downhill perhaps that could explain why your rear end would break loose....
Dickson
 

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If your where at the crest of the hill, even with the weight of your motor, the suspension in the front gets light. Any suspension deficencies get magnified. A bad bump steer condition could occur suddenly and as the rear gets light as it crosses the hills crest with this occuring, guess what goes it's own way. I would first check all front suspension components, replace the front shocks (first if you can't afford front and rear at once) and then get a good alignment shop to check the front end. Bob.
 

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One thing just came to mind. what you may be experiening rear wheel wheel horsepower. A car like the mustnag you must DRIVE! Its not a given like it is on a honda. Most cars are front wheel drive so the car is pulled. in any condition your best move is to keep it floored when your driving it hard. The mustang is rear wheel drive. They have a tendancy to want to fishtail. and if you gun it then your going into a spin. Hell if you turn the front wheels all the way into one direction and hit the gas you will make a huge doughnut in the road.

Let me try to explain to you the theory behind why rear wheel drive is the only way to be and its limitations. The reason that the industry switched was to strip weight off the vehicle and it was a whole lot cheaper and easier to build the tranaxle sub assembly as a unit and just drop the whole thing in assembled.

The most important part of the traditional rear wheel drive setup is enough room. There is enough room to build real power. There is no replacement for displacement. Equally important isweight distrobution. When the car is just driving around the weight is distributed fairly evenly 60/40. But from a stop and pointed straight the natural tendancy of the car is to lift the front end. This lifing is transfering weight to the back end. If you were building the car for drag racing you'de let the front end to have a bit more bounce to increase the weight transfer. A car that is able to pull the front wheels has 100% weight transfer to the back wheels. This is what gives rear wheel drive cars the track advantage. There is simply no way in a front wheel drive car to have 100% of the weight on the power wheels for traction.

The front end on a mustang is a typical A-arm setup with springs and shocks and a sway bar. Heavy springs up front prevent the body from too much movement, the shocks dampen the springs and the sway bar transfers weight across the car in turns. You can replace the ruber snubbers on the front end with plastic ones and the car will feel a bit crisper, they will be red so there'll look good but overall effect is minimal. Changing the diameter of the front sway bar will make some difference in handling. Bigger is not always better but it usually is. The advice to get aluminum heads gives both power and it is a great place to loose 50# off the car. The shelby mod is designed to lower the center of gravity of the front end. The lower a cars center of gravity the less body roll. So it is better to eliminate body roll than it is to conteract it with taction bars which is better than not dealing with it at all. Power steering was fairly new back in the 60's. People were used to manual steering which in order to reduce the energy it took to turn the wheels they used gearing to make it easy. So a mustang is like 3 turns lock to lock. Modern cars are about half that. So to get a better feel you can either get a tighter ratio steering box or convert to rack and pinion which is real nice and real expensive.

The rear suspension is a bit primative but works fine. The leaf springs and shocks try to keep the rubber on the road. You can add a rear sway bar to transfer weight in turns. Traction bars are a nice addition. They tie the leaf spring to the body of the car which prevents the spring from twisting which is a ral bad thing when the wheels unhook from the road and the twist comes out of the axle and makes the wheels start to hop. A limited slip differential prevents one wheel from spinning by itself when you accelerate. So either you get 2 wheels driving to push you forward or both of them will be spinning. There are also a couple kinds of cross bars that prevent latteral movement of the rear end under hard cornering.

Weight that is spinning costs more to performance than weight that is stationary. That is why alloy or alluminum wheels are good. It takes less energy out of the suspension to top the bounce. Wide tires increase traction. The primary reason that a car wants to come around is the wheels are not in contact with the pavement and all the acceleration is coming from one side of a car. This is similar to a tractor with a duel brake setup. you can mash on just one of the brakes and the tractor will spin around in spite of the fact the wheels are pointing straight. in fact it will drag the wheels sideways in order to pivit on the locked wheel.

Front drum brakes suck. 2/3's or more of the braking power of the car comes from the front end. The reason for this is weight transfer. when you stop hard the cars weight gets pitched forward. So if you don't have front discs you probably should. The rear drums stop almost as well as rear disc brakes which is why there still common on new cars.

Then there is aerodynamics which pretty much sucks on older cars. The mustang tends to collect too much air under the hood. This is why the shelby's had a vented hood. For most models there are front spoilers and some have back ones. They would help for speeds over 75 mph.

Finally there is the driver. You have more power than your can use. It is your job to control the power. The winning race car driver is the one who can find a few more places on the track to put out more power then the other guy. There all driving roughly the same setup. If your in a turn and punch the gas you will go into a spin. This is not front wheel drive. Wait till your past the apex of the turn and drop the hammer coming out of the turn.Where the mustang will win the race is in the straighaways not the turns. They excel in straight ahead acceleration. I saw a fox bodied CONVERTIBLE mustang yesterday that could do 9's in the quarter mile and he ran it over 200 on a track. i doubt the car could do 1.0 G's on a skid pad.

As if this isn't already a long enough reply i had the reverse problem. I grew up with rear wheel drive where you lift your foot off the gas going over ice covered bridges. Well i was driving a front wheel drive citation on a freeway crossing the bridge and did that. the next thing i knew i was looking out the front widshield at the guy behind me going backwards at 60 mph. We both had a pretty shcked look on our faces. I manages to spin the car back around and get off the road. That was the scariest experience i ever had driving. Gravel roads are just like snow covered roads. Its real easy to fishtail the back end around.
 

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14" tires and 500 horsepower is NOT a good combination!!!!
 
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