Track days Toyo RA1 tire pressure /size recommendation
04-09-2007, 01:46 PM
#21
Originally Posted by Fab_vr6
On my other post, I have asked a question about trailbraking in the Z. How's everybody's experience in this? I prefer to be able to brake a bit later and trail the brakes into the corner but I never purposely did that on the Z from what I've been hearing ( I guess I will find out if I just try it, but I want to see what you guys think).
That being said, it works very well with the Z
04-09-2007, 06:00 PM
#24
Originally Posted by tmak26b
Trail braking only works if you have good tires. You go too deep into the corner in the Z, you are going to be in trouble.
Nah, it works fine regardless of tire.
The idea is to change the car's balance. So unless your tires are missmatched terribly, you'll get the car to rotate.
04-09-2007, 06:50 PM
#28
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Like mentioned above trail braking is a fix for an under steering car. with 275's all around i never noticed even a hint of under steer. the cars naturally wanted to oversteer. you should be able to setup a pretty good line and gass earlier and still stay on that line compared to a staggered setup. your turning input is crucial to prevent the car from coming out of the corner *** first so be precise .
Hammad
Hammad
04-10-2007, 05:02 AM
#31
Originally Posted by tmak26b
Let's wait for the next guy to lose it going into the turn
But I'm curious to know how you came up to the conclusion that trail braking is harder/more dangerous with regular tires vs r-compound? I tend to disagree and think that trail braking is much easier to learn on street tires and it's more useful in limited grip situation.
PM me if you want.
04-10-2007, 08:47 AM
#32
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The problem with trail braking on street tire for novices is that street tires simply cant hold as much load as the R compounds. If someone gets too brave and drive too deep into the corner, you are going to have a spin. I agree 100% that people should learn on street tires as they do give you better feedback (the re040 were really good in that department), but they are definitely not something you want to try something crazy with. If you can trail brake, that's great. If you are just starting out, I would be very hesistant about doing it with limited grip. It doesn't take much to lose control with the street tires on the track. Lastly, R tires don't like to go sideways. If you do end up in a small slide, the R compounds will simply grip and get you straight without any other inputs
04-10-2007, 09:07 AM
#33
I have experienced just the opposite for slip angle control. Street tire traction curve is smoother and more linear than R compounds. While the R-compound had greater peaks, it's drop off rate is much sharper. So while your overall grip is better with R's, they don't communicate as well and can bite you if you over drive them.
While I wouldn't recommend trail braking to ANY novice, no matter what they are driving or the tires they have, it is a good technique to have later on down the road. Before I would recomend trail braking I would try slight throtte lift to a mid-advance student, then trail braking. All on street tires.
While I wouldn't recommend trail braking to ANY novice, no matter what they are driving or the tires they have, it is a good technique to have later on down the road. Before I would recomend trail braking I would try slight throtte lift to a mid-advance student, then trail braking. All on street tires.
04-10-2007, 09:21 AM
#34
IMO, trail braking is much better learned on street tires and on a car the is slightly biased towards understeer. With street tires, there is greater slip angle threshold which helps you trail brake deeper.
Also, I go back and forth between a square r-comp setup and a staggered street setup at the track. I can trail brake with more confidence on the staggered street tires. On the square r-comps, I have to be on the throttle sooner to keep things smooth (or from spinning on entry). With that respect, I prefer the staggered setup, and will go with 255/275 r-comps next time around.
On another note, someone just mentioned to me that the Toyo R888's are finally coming to our shores, and the RA1's might be phased out (if not already). Is this just another rumor?
Also, I go back and forth between a square r-comp setup and a staggered street setup at the track. I can trail brake with more confidence on the staggered street tires. On the square r-comps, I have to be on the throttle sooner to keep things smooth (or from spinning on entry). With that respect, I prefer the staggered setup, and will go with 255/275 r-comps next time around.
On another note, someone just mentioned to me that the Toyo R888's are finally coming to our shores, and the RA1's might be phased out (if not already). Is this just another rumor?
04-10-2007, 03:49 PM
#35
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I agree the traction curve is smoother, but you have no margin of error if the driver overcooks it. When I instruct, I tell them to not do it unless they can demonstrate good car control skills.
Originally Posted by mhoward1
I have experienced just the opposite for slip angle control. Street tire traction curve is smoother and more linear than R compounds. While the R-compound had greater peaks, it's drop off rate is much sharper. So while your overall grip is better with R's, they don't communicate as well and can bite you if you over drive them.
While I wouldn't recommend trail braking to ANY novice, no matter what they are driving or the tires they have, it is a good technique to have later on down the road. Before I would recomend trail braking I would try slight throtte lift to a mid-advance student, then trail braking. All on street tires.
While I wouldn't recommend trail braking to ANY novice, no matter what they are driving or the tires they have, it is a good technique to have later on down the road. Before I would recomend trail braking I would try slight throtte lift to a mid-advance student, then trail braking. All on street tires.
04-10-2007, 05:57 PM
#36
Originally Posted by tmak26b
I agree the traction curve is smoother, but you have no margin of error if the driver overcooks it. When I instruct, I tell them to not do it unless they can demonstrate good car control skills.
Internet is prone to missunderstanding, don't take this too arshly as I might be wrong. But you make it sound like you've never threaded a car in the slip angle envoloppe of its tires. If you had, you would know that a street tire has tons of leeway when driven at the limit. A race tire is much harder to keep balanced.
As for instructing, basic training dictates that when a new technique is tested, speeds must be reduced accordingly. The grade of the tire should be taken into consideration when judging the appropriate speed for your student, but it has little to no impact on what can be taught.
04-10-2007, 06:09 PM
#37
Kolia is right. It is much easier to learn trail braking and slip angles with a street tire. They are also very "talky" compared to DOT-R and slicks, and that helps to get the feel before moving up. Lots of leeway to deal with streets compared to DOT-R. And as for slicks? They "whisper" and then are gonzo. Very very tight tolerances.
04-10-2007, 07:02 PM
#38
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Originally Posted by Eagle1
Kolia is right. It is much easier to learn trail braking and slip angles with a street tire. They are also very "talky" compared to DOT-R and slicks, and that helps to get the feel before moving up. Lots of leeway to deal with streets compared to DOT-R. And as for slicks? They "whisper" and then are gonzo. Very very tight tolerances.
+1 - street tires give much more feedback and are much easier to find the limits of safely...when they start to slip, you can usually controll it (if you're not too far out of shape)
R-comps have a much thinner transistion from static to kinetic friction...there's less warning when they're going to break traction. (you can get much much faster times, but when you loose traction, it'll be harder to catch and keep things in control)
-Peter
04-10-2007, 07:26 PM
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I don't think you are getting it. I know the difference in grip and feel between the two tires. What I tried to say is that if you try to be brave on street tires, you are going to get yourself in a lot of trouble simply because they don't have the grip like the R compounds. Pushing a street tire at 100% is like pushing a R compound at 50%. You might have better feel on the street tire, but you just don't have a chance to overcook a corner. It's your choice, but I would never tell a relative new person to trail brake on street compounds. If he tries to drive it more than 100%, we have no place to go but to spin.
Nope, I have never slide the car before. I just used 18 tires last year to make rubber bumpers.
Nope, I have never slide the car before. I just used 18 tires last year to make rubber bumpers.
Originally Posted by Kolia
If the traction curve is smoother you DO have more margin for error... That is what a street tire is designed to do.
Internet is prone to missunderstanding, don't take this too arshly as I might be wrong. But you make it sound like you've never threaded a car in the slip angle envoloppe of its tires. If you had, you would know that a street tire has tons of leeway when driven at the limit. A race tire is much harder to keep balanced.
As for instructing, basic training dictates that when a new technique is tested, speeds must be reduced accordingly. The grade of the tire should be taken into consideration when judging the appropriate speed for your student, but it has little to no impact on what can be taught.
Internet is prone to missunderstanding, don't take this too arshly as I might be wrong. But you make it sound like you've never threaded a car in the slip angle envoloppe of its tires. If you had, you would know that a street tire has tons of leeway when driven at the limit. A race tire is much harder to keep balanced.
As for instructing, basic training dictates that when a new technique is tested, speeds must be reduced accordingly. The grade of the tire should be taken into consideration when judging the appropriate speed for your student, but it has little to no impact on what can be taught.
04-10-2007, 08:36 PM
#40
Being "brave" on any tires, anywhere, is asking for trouble. If a student tried to be brave with me as a passenger, I'd warn him once and kick him out the second time he did it.
The OP has made it clear on post #19 that he does know how to trailbrake when he asked our opinion on the use of the technique on the Z. He is not the total newbie you might think he is.
For which organization do you instruct?
The OP has made it clear on post #19 that he does know how to trailbrake when he asked our opinion on the use of the technique on the Z. He is not the total newbie you might think he is.
For which organization do you instruct?