Flat spotted tires?
#29
You don't need a proportioning valve, you need more practice. In Spec Miata brake pads are free but the remainder of the brake system must remain stock. The Miata system is extremely capable in stock configuration with racing pads. It is all about brake modulation, threshold breaking is not simply a matter of jumping on the brakes as hard as you can. If you brake that way you are going to lock up all the time. You need to learn modulation, standing a car on its nose is not the fastest way around the track, or the most efficient way to brake.
Enjoy the practice, there is nothing better than driving on a closed course!!!
Enjoy the practice, there is nothing better than driving on a closed course!!!
#30
You don't need a proportioning valve, you need more practice. In Spec Miata brake pads are free but the remainder of the brake system must remain stock. The Miata system is extremely capable in stock configuration with racing pads. It is all about brake modulation, threshold breaking is not simply a matter of jumping on the brakes as hard as you can. If you brake that way you are going to lock up all the time. You need to learn modulation, standing a car on its nose is not the fastest way around the track, or the most efficient way to brake.
Enjoy the practice, there is nothing better than driving on a closed course!!!
Enjoy the practice, there is nothing better than driving on a closed course!!!
Also he now has wilwood 4 pot calipers up front and still the stockers in the rear. He needs RX7 rears now with a prop valve for some super awesomeness
#31
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It seems to work a little different with turbo miatas. We carry a lot more speed into corners whereas a spec miata is exercising its ability to fly around the track hitting the brakes as little as possible.
Also he now has wilwood 4 pot calipers up front and still the stockers in the rear. He needs RX7 rears now with a prop valve for some super awesomeness
Also he now has wilwood 4 pot calipers up front and still the stockers in the rear. He needs RX7 rears now with a prop valve for some super awesomeness
#33
That is true, didn't realize the brake upgrade. But it is still about modulation, a proportioning valve will help but you still can't stand the car on its nose during breaking.. Giving up a little entrance speed to maximize exit speed will always result in faster lap times.
#34
That's when tune, throttle modulation and brake modulation come into play. Not to mention tires, suspension setup, weight distribution on the car ect ect ect. Neither the brakes or the throttle should ever be treated as on off switches on the race track.
It's tough with the 200hp I have with my conversion, I am sure it is even harder with FI and 300hp. But that is why they make sticky tires great brakes and tunable suspensions. Then it's just a matter of fine tuning the weakest link in any race car...the driver
It's tough with the 200hp I have with my conversion, I am sure it is even harder with FI and 300hp. But that is why they make sticky tires great brakes and tunable suspensions. Then it's just a matter of fine tuning the weakest link in any race car...the driver
#35
Agree w/ hingstonwm. Take the rest of your tires life and practive threshold braking. If you are going to drive a fast car w/o ABS, then you need (repeat need) to be good at threshold braking. Now you have a good set of tires to practive with. Learn to recognize the onset and feel and modulate the brake pedal accordingly. Good luck and have fun.
#36
I'm just going to toss in my The car is absolutely insanely easy to lock up the fronts on. I like to think I have a pretty delicate foot on both the throttle and the brakes ( I have to, I live in Seattle and my car will ******* KILL YOU in the rain if you aren't careful) and Jason's car surprised the **** out of me on Saturday. The brakes are like an on/off switch. No feathering, no easing into it, it feels like nothing is happening, and suddenly about 1/64" further down you are headbutting the dash/wheel. The car needs more prop valve and less internet bench race coaching.
#37
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After giving the flat spotted tires a once over I decided that they are finished. Any additional burnouts will push them through the cords.
As for practicing threshold braking, that's the idea, hence how I did this to begin with.
As for practicing threshold braking, that's the idea, hence how I did this to begin with.
#40
I'm just going to toss in my The car is absolutely insanely easy to lock up the fronts on. I like to think I have a pretty delicate foot on both the throttle and the brakes ( I have to, I live in Seattle and my car will ******* KILL YOU in the rain if you aren't careful) and Jason's car surprised the **** out of me on Saturday. The brakes are like an on/off switch. No feathering, no easing into it, it feels like nothing is happening, and suddenly about 1/64" further down you are headbutting the dash/wheel. The car needs more prop valve and less internet bench race coaching.
If you are locking up the tires, you are to heavy on the pedal...period, or there is a problem with the set up of the system, a brake bias valve will not fix this. Rear brakes will help the car stop but the majority of the braking is up front where the weight shifts to during braking. Changing balance will allow you to dial in the best performance, but it wont keep tires from locking up, that is the job of the loose nut behind the wheel. If they are that much of an on/off switch there may be an issue with the brakes. Calipers, pads, rotors, lines, who knows but there may be a mechanical issue. Tires have a finite amount of grip. If you are using the grip for braking, then you have less grip left to initiate turn in and to carry momentum through the corner.
As a racer your car changes through the course of an event. Brakes get hot and fad a little, tires get hot and lose a little grip, engines get hot when you run in a draft. My point to this is you need to adapt to the conditions, weather the conditions are those of the car or the track.
Indy cars and F1 cars have brakes so strong that they can lock the fronts at 200 mph, even with brake bias. Ever wonder why you don't see everyone in the field flat spotting tires? Brake modulation.
I was not harsh with my suggestion of practice makes perfect. I was not a dick when I said the fastest way around a track was not to stand the car on its nose in every corner. I was stating fact and did not attack you friend.
Road courses are nothing more than a bunch of drag races connected by a bunch of corners. All cars no matter how much power they have are momentum cars. The more momentum you can carry through a corner on exit the faster you will get down the straight to the next braking zone...the faster your lap times will be.
Slow in fast out is the way you go fast in any car. I know we are talking road racing here but probably the easiest example of slow in fast out to visualize is in NASCAR. How many times have you seen a guy try a dive bomb move only to slide up the track, or watch the guy he just passed drive back past him at mid corner. By slowing down you can get the car settled, change direction and get back in the power sooner, basically causing the next straight away to be longer, since you are accelerating as the other guy is still braking because he drove so deep into the corner.
I have not be an *** with my previous remarks, furthermore all I have done with this post is state racing fact, I have not attacked anyone.
As for weather I am talking out of my *** or not, you be the judge. It has been a few years since I have raced, 5 years in fact. However, the last two years I raced in a total of 38 events, and finished off the podium only 3 times. Finishing second in the points to the current T3 national champion in the SCCA both seasons. I only mention this to add credibility to my post.
If the car needs a proportioning valve then get one, but don't expect it to magically fix the front brake lock up because it, wont unless you dial all of the front out, Best regards.