SS brake lines are something that I personally think should be mandated by FMVSS and other regulating bodies. It really comes down to a biomechanics question: the human body is designed to respond to force/pressure feedback, not position feedback. We don't have nerves that "sense" their position relative to a given location, but we do have a complex system that can tell our brain exactly what each muscle is doing and feeling in terms of output and feedback at any given time (let's call this impressive network "touch"). A firm brake pedal that varies braking effort with force applied would be more intuitive to most drivers, I'd suspect, after the inital adjustment of not having any movement feedback from the pedal. Hop in any decent racecar or older sportscar and push as hard as you can on the big red pedal. Its not going to go far. I've seen and built pedal assemblies where the majority of pedal movement was actually due to my lack of designed bending stiffness rather than the master cylinders moving to push fluid around.

 

I disagree. Kevlar wrapped lines are stiffer, lighter, cheaper, and less prone to catastrophic failure. Rubber lines with a Kevlar braid will also last longer. The only thing braided stainless does well is survive off track incidents.

I only bought braided lines for my Supra because they cost half what Toyco wants for OEM replacements.

I've put braided lines on a number of street/race motorcycles. Brake feel is critical on a bike. The difference between the current crop of OEM lines and braided is tiny. Really tiny. Kawasaki put Kevlar braided lines on the ZX-7R way back in '92 for all the right reasons. It's hard to improve on them.

 

IMO, competition driving besides winning is about feeling the cars response to a specific input. it could be anything from the cars tendency to oversteer, understeer, noise and sight. theres no better feedback than the actual driver who's driving that car. majority of the race car drivers all tuned to the specific car they are driving and they all give feed backs to the pit crew so proper adjustment could be made so the driver/car can be faster. if replacing brake lines is going to help in that area of response than to me its well worth the money. you need to feel what the car is doing before you can determine what area of the car needs attention.
mechanical pieces of a car can be made better and stronger theres really no limit if the pocket is deep enough. the real limit is really up to the driver. like the old saying, you can put a 100% driver into a 80% prepared car, he'll beat the 80% driver in a 100% prepared car any day.

 

I got schooled by a 100% driver in a Civic wagon around my favorite turn one day. I happen to know the guy, and I was chasing him. He was getting away. I was in a much better car. I later drove the same car. It had an inch of play in the steering, sloppy brakes, and rolled into turns like a Conestoga wagon.

Feel is totally overrated. Feel means nothing to a truly fast driver. They know how to overcome any limitation the machine is suffering, and they know how to get the most out of the machine regardless of tuning. They don't tune to make the car feel better. They tune to make the car faster. If the driver has to work harder to make that happen, such is life. All this BS about feel is coming from people who really haven't had the opportunity to race in a real racing vehicle. I've already had these discussions with chassis tuners. They couldn't care less if the driver likes how the car feels. They only care about one thing: is the car faster or not.

 

like i said its all in the driver's limit. I am not trying to start anything here, but for a good/fast driver to DEVELOPE the skill, they have to know what the car is doing no matter what stage of their game is on. without actual feel of what the car is doing there's no way you are going to be going fast or attempt to reach your driving limit.
those chasis tuners might care about one thing because that's their job, look at what they are doing. no matter what it is, theres a huge gap from someone racing in amature level to professional level and to close the gap is to develop driving skills and one of those involves "feel".

 

I've only bothered with SS brake lines on 1 car, and didn't notice any difference at all even on the track with track pads and R compound tires, so I never used them again. I doubt you would notice the difference between OEM and SS either if that was the only modification AND you had fresh brake fluid for both sets of lines. If I remember correctly, SS lines aren't technically street legal either since they aren't DOT approved.

 

Have you tested your ABS to see how well it works with the larger calipers? I assume that there are other differences in hardware and / or software between the 250 / 350 that you left unchanged.

 

Enzo Ferrari to Phil Hill, "maybe the problem is your right foot."

 

The ABS system worked just fine, along with trac and vsc. only thing i did not change are the vsc ecu/actuator, so far no major issues with system operation. there were not much in hardware difference between the two. i had to trim the rear backing plate to fit the rotors thats it. the 250 doesnt have VDIM so upgrading hardware will be the same as anything aftermarket(ie. rotora,stoptech etc.) except this is from factory.

I will be taking the car to LimeRock this weekend, i'll have a better idea once we are on the track.

 

according to stoptech website, all the SS lines they carry are DOT approved.

http://www.stoptech.com/products/sta...al_lines.shtml

 

Did you replace the master cylinder, or are they even different?

 

nope,i did not replace the master cylinder. it should be the same with the exception of the fluid reservoir. i have a 6 spd manual and the clutch reservoir shares the same reservior as the brake fluid.

 

What about the ABS solenoids, electronic brake distfibution, and electronics? I think these will be pretty important for the results you should be looking for.

 

I agree. the abs/vsc solenoids are all in one unit within the VSC actuator which house the the VSC ecu you can not just change that from an 250 to a 350 due to VDIM. it has a separate ecu just for that.
those electronic software are calibrated to act base upon the yaw rate, accel/decel rate, vehicle speed and steering angle etc. change in rotor size and caliper should not matter. if anything the increase of decel. rate would bring the effectiveness of EBD earlier..... any thoughts ?

 

You should read this before making statements like that. There is a lot of engineering that goes into ABS/EBFD to make it predictable (even though my SOTP experience with the OEM brakes tells me EBFD is not really predictable).

My experience with changing anything in a fully capable ABS system is the hard numbers will not be as good if you change things without changing the ABS ECU.