[tpafire5]

is there much of a difference between the pro kit and the sportlines. i don't want to sacrifice comfort, but i can get a barely used set of sportlines for around 100?

[SportsPix]

Originally Posted by tpafire5

is there much of a difference between the pro kit and the sportlines. i don't want to sacrifice comfort, but i can get a barely used set of sportlines for around 100?

Hi tpafire5,

Yes there is a huge difference in ride height between Eibach's Pro-Kit and Sportline springs. Pro-Kits are as low as you can practically go on an S197 chassis driven on the street even if you keep the tallish 27" tall stock wheel and tire dimensions. If you install Sportlines and buy aftermarket wheels and tires (most common 18"-20" combinations end up shorter by about 1"), you will end up with a VERY low car that scrapes all the time going through driveways and even dips in the street.

The problem is caused by the fact that there is not much suspension travel available at the rear of the S197 chassis and the Sportline springs eat into that very limited suspension travel even more than the Eibach Pro-Kit springs. A car that is riding on the bump stops frequently is a car without suspension frequently and this makes the car very spooky and poor handling and when driven hard or on the race track downright dangerous. If you look carefully at the real race springs offered by folks like Steeda, H&R that actually RACE what they sell they do not lower the car this much because it messes up the suspension geometry and consequently grip and handling performance.

The other problems which are actually worse than simply scraping all over town is the fact that Sportlines will have your car's suspension geometry all messed up front AND rear and also make the axle ride on the rear bump stops much of the time and shifts the rear axle far off the centerline of the car. Suspension geometry is what makes up a car's handling grip and feel of the road. Lowering the car too much alters the S197's suspension geometry and not in a good way. Excessive lowering reduces rear traction on launch, increases brake dive in front, increases braking distances and increases the car's rear axle steer during cornering. If none of this sounds very good to you you're right.

Be careful in your spring choice.

Cheers/Chip

[steve999_1]

Originally Posted by tpafire5

is there much of a difference between the pro kit and the sportlines. i don't want to sacrifice comfort, but i can get a barely used set of sportlines for around 100?

If you dont want to sacrifice comfort then don't buy the Sportlines. I have them and the ride is hard - they make a lot more of a difference to the ride than the 20"/35 rim and tires do.

In terms of appearance there wont be a huge difference only half an inch at the rear I think, but this half inch makes a big differnce to ride as there is not much travel left with the S'lines. I have not had any touching on normal or bumpy roads but occasionally I had contacted the X pipe which sits very low - usually happens when going from a ramp to a car park.

Low speed handing with the S'lines is fine, you can corner hard and the car stays pretty flat but I do get a bit uncomfortable on higher speed >60mph corners. The cars seems very twitchy and bouncy even with various adjustments on D-spec shocks. I would go for the Pros over the S'lines - that's what I thought I was getting but too late now / too much $ & time to change.

Sportspix, would appreciate your view on the following as you have already replied to this thread and it may be related to the S'line springs. I have noticed when making slow turns say more than half turn on the steering wheel, that the car is making sort of creaking, groaning noises - sounds like something is under stress. I thought it might be the alignment. However, the tires are wearing nice and even with no sign of scrubbing. Any ideas ?

[SportsPix]

Originally Posted by steve999_1

If you dont want to sacrifice comfort then don't buy the Sportlines. I have them and the ride is hard - they make a lot more of a difference to the ride than the 20"/35 rim and tires do.

In terms of appearance there wont be a huge difference only half an inch at the rear I think, but this half inch makes a big differnce to ride as there is not much travel left with the S'lines. I have not had any touching on normal or bumpy roads but occasionally I had contacted the X pipe which sits very low - usually happens when going from a ramp to a car park.

Low speed handing with the S'lines is fine, you can corner hard and the car stays pretty flat but I do get a bit uncomfortable on higher speed >60mph corners. The cars seems very twitchy and bouncy even with various adjustments on D-spec shocks. I would go for the Pros over the S'lines - that's what I thought I was getting but too late now / too much $ & time to change.

Sportspix, would appreciate your view on the following as you have already replied to this thread and it may be related to the S'line springs. I have noticed when making slow turns say more than half turn on the steering wheel, that the car is making sort of creaking, groaning noises - sounds like something is under stress. I thought it might be the alignment. However, the tires are wearing nice and even with no sign of scrubbing. Any ideas ?

Hi steve39s,

Your ride is hard? I'm running Eibach Pro-Kit springs with D-Specs and run then in my daily driver at 2.5F/2.5R and have a fair ride with excellent body control. I'm on the stock '05 17" bullets because I won't wreck my ride for a bit more dry grip and I prefer a bit of throttle steering to play with in the canyons that a wider tire would take away. For race track events I'm working on finding some light, cheap forged 18"X9" wheels so I can run wider, sticky tires. For long rides with the wife I turn the D-Specs down to 3.5-4.0F/3.0-3.5R (depending), and have a stock like ride with better than stock body control. Are you running any suspension components with rod ends or solid bushing materials?

I ask because the Sportline spring rate is the same as the Pro-Kit spring rate though the spring rate has to rise faster on the Sportlines to compensate for the extra lowering of the chassis. That twitchyness is due to the rear axle hitting the bump stops which instantly transfers all of the load to the chassis instead of loading up through the spring perch. This is the bad part of lowering the S197 chassis too low.

The Sportlines I installed for a local guy with an S197GT lowered his car .25" in front and .7" more than the Pro-Kits I had previously installed for him. I measured both right before and after the spring swap using a chassis ride height gauge. The front is pretty low but the rear axle was less than an inch off the bump stop in his car with a full tank of fuel. I also had to readjust his Panhard bar to get his axle centered right. I gotta say it does look pretty good though I think I should have only swapped out the rear springs as the front is too low now. A few days later He called me and was complaining about the same thing you are, bouncy twitchyness that he did not have before when pushing the car hard. He's not a racer more a cruiser and show guy so I doubt he's going to swap them back.

I think your low speed, sharp turning noise is the limited slip diff clutch plates. It sounds sort of like a moaning or groaning (the same sound I usually make when I have to get up too early), usually when the car is cold though it can also do it when warm sometimes when starting from a stop and if the turn is sharp and you are on the gas a bit. I thought there was something wrong too but this noise is simply the rear end, no big deal, I get this too but I don't want the dealer to fix it. Why not you ask? Because their solution per the Ford TSB is to add a friction modifier additive package that reduces the grip of the clutch pack or sometimes to replace the clutch pack all together. Personally I want my limited-slip diff to grip and spin both wheels if I'm launching in a straight line. One stripe bad, two stripes good! Mine does that so I'm leaving the diff alone.

I hope this helps!


Cheers/Chip