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  • 2 weeks later...

1.06.7 at Wakefield on a drying track.

Car feels good now. Back to a nice level handling and power wise. Brakes let me down thou again. Probably a whole second in there with better brakes Think i'm going to have to bite the bullet soon as the stock Brembo's just aren't keeping up with the rest of the car.

I would be amazed if there was a second in lap times around Wakefield in better brakes. Especially if that second is putting you into the 1:05s. (im talking over a single lap of course)

Great time though....its the one track where GTRs struggle because of corner speed, so obviously the car was working well. Did you have fresh rubber or the same rubber from PI?

I had a few beers after work tonight and revealed my admiration of Chris and his laptime. That wayward comment was quickly followed by my GTSt can do low 1:07s so dont get too excited about expecting free handjobs from the pit girl crumpet :)

PS.LOL, like all my laptimes its purely hypothetical that i can do 1:07s :blush:

Yeah that's on old rubber too - Same fronts tyres as PI, but I put some others with 40% left tread on the rear.

I stand by one second in brakes. Ask Ant - he was in the passenger seat. Three corners where I have to get off the gas very early and apply brakes for much longer than I would like too. 3x 0.25 = 0.75 of a sec = 1.05's easy.

Yeah that's on old rubber too - Same fronts tyres as PI, but I put some others with 40% left tread on the rear.

I stand by one second in brakes. Ask Ant - he was in the passenger seat. Three corners where I have to get off the gas very early and apply brakes for much longer than I would like too. 3x 0.25 = 0.75 of a sec = 1.05's easy.

Id be inclined to say 1:05s with fresh rubber, but i am always hesitant to drop times because of better brakes. Look at it this way. Go to the drags and see the amount of car lenths there is between a car that does 12.0 and a car that does 12.75. So you are saying that under brakes you would be able to pull a similar gap???? Thats how i look at it.

No doubt better brakes will help, and i love my brakes...but just some thinking why you may not find such a drop in time with bigger brakes?!?!?!?!?!?!?

We're coming Troy! Engine bay is completely stripped now, engine is back, waiting on plenum and a few other bits and pieces and we're good to go!

Haven't seen Ray's car yet, really need to pop down there and do some spying... I mean say hello :)

If it was top 14 times I might just sneak back into Sandown... unlikely though :rofl:

No doubt better brakes will help, and i love my brakes...but just some thinking why you may not find such a drop in time with bigger brakes?!?!?!?!?!?!?

Genuine question here Troy - Have you driven a car at the track that you can't brake 100% every turn? I'm thinking maybe you've never had the issue of not being able to brake as hard and late as possible everytime. I think it's hurting my times a touch because I have to be nice to the brakes, so most of the time i'm only braking at 80%.

As for top 14, just make it top 15 - bit more round of a number.

Its amazing to see hof far the times have dropped. 3 years ago 1:25 was the quick time at Sandown. Now you have to be in the teens. I have a little trick for the RB20 that may see it get into the 1:20s, but without 350kws i will never do a teen :)

D.amn, should have run my time a few years ago!! :rofl:

Genuine question here Troy - Have you driven a car at the track that you can't brake 100% every turn? I'm thinking maybe you've never had the issue of not being able to brake as hard and late as possible everytime. I think it's hurting my times a touch because I have to be nice to the brakes, so most of the time i'm only braking at 80%.

Well depends on what you mean by not being able to brake 100%? Firstly, if i want to be a dill, i doubt you should even be braking 100% every brake application. Its a recipe for locking brakes, missing apexes, carrying a bit too much speed on corner entry and in turn hurting corner exits etc etc. You need to brake as late and quickly as possible, but you need to be able to do it consistantly over a lap which to me means i always need to keep a little up my sleeve when braking.

For almost all of this year i have had trouble stopping the car...in my case because my car used to pitch so much under brakes the car would wobble everywhere. So i wasnt braking 100% because of a stability problem, more then a brake fade thing. Is it the same outcome/result? Depends on how bad the fade is i guess, but it did hurt braking a lot ;)

Then going back a few years i had a problem with bad pad knock off so i did a day at the track where i was left foot braking and forever pumping up the pedal as i had a really soft pedal....wasnt nice but i think i still did a 1:56 or something (remember the day you and i had a woopsie at Honda/PI...the car still stopped fine even though going by the pedal it was horrible) Then a few weeks later had the same knock off problem at Sandown but still did a 1:24. That was my first time there in the dry so dont know if it was costing me time.

But you are right, generally i have never really driven too many cars that struggle for brakes. Even when my car smoke the std 280mm rotors it was still stopping fine.

But here is the thing. :D Im not saying i am 100% right, or even partly right. Just sounding off on some thoughts from what i have experienced, what i have read and what the data logger tells me. if your experiences tell you different then go with that. :(

I have read (???? i have never had to qualify / race so i would not know???) that braking is the easiest place to lose time and the hardest place to make time. Also, the feel of what your brakes are doing, or not doing greatly impacts on your perception of how the car is actually stopping. Because you dont have the retardation that you expect you think you are losing time, reality is you are actually walking up to the corner quicker...ok you tend to jump on the brakes to wipe off speed a little earlier which counters this. But its a trade off. What feels fast is not always fast, what feels slow is not always slow,

Case in point is when you sit back and look at the info i get from my data logger. Its surprising how small the improvements are when you brake later. You see over the day as i brake later and later the times dont really improve. What helps the times is when my corner speed improves. With me driving braking later doesnt automatically mean better corner speeds. So for me (my driving style) the data tells me that braking later does little for my lap times.

Whe i first started reading the data this puzzled me a little, and wondered why this is the case and started to think aboutsimple motion euqations, v=u+at. V is final speed, u is initial speed, t is time and a is acceleration (-ve as we are decelerating, this is all greatly simplified as it assumes acceleration is linear, which it is not, doesnt take into consideration a whole bunch of things but still makes a point)

So say your car decelerates/brakes at about 6m/s2. And you brake a full 1 second earlier. That braking 1 second earlier increases your braking distance by a huge amount since say at the end of Sandown you are travelling about 65mtrs per second. Now as far as elapsed time is concerned....braking 1 second earlier means you have lost 1 sec of acceleration and say you are now travelling at 198km/h rather then the 230km/h since you have been braking for 1 second already. So that 32km/h equates to about 8mtrs per second. So the time you have lost is the increase in time it took you to cover that 65mtrs whilst braking from 230 to 198km/h rather then reavelling at 230km/h. I had a spreadsheet on my old lap top playing with some basic equations / plotte dgraphs then the more complex braking equations. But...like i said, its all theory mixed in with a little practice but of course you lose time by braking early, but the old watching the cars at the end of the drag strip help reinforce the point. A car that is only 5/10s of a second quicker over the quarter mile passes the lines many car lenghts ahead of the slower car, yet it is only 0.5 seconds slower. Now can you imagine braking that distance later to try and make up 0.5 seconds? Even over a number of corners? :P

But, that all said, no doubt that if the brakign performance of the car is suffering then there is to be an improvement with a brake upgrade. Im just yet to be convinced that it is in the magnitude of seconds, all other things being equal:spam:

So, welcome the thoughts of others.... im happy to be proven wrong if it means i end up with the facts :)

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