R32 Gtr Build For Superlap 2012

[benm]

SuperLap has and always will be an event designed for workshop cars.

[sycorb]

so much HATE Duncun lol

[Marlin]

SuperLap has and always will be an event designed for workshop cars.

^^^ And there you have it

However, if you're one of the lucky ones who seem to have an excess of CASHHHHHHH then I say have a crack at it. But go in with your eyes open and have realistic goals.

[Roy]

Good luck to anyone who enters knowing what they are getting in for, they are providing a great spectacle for the crowd. But for mortals on a normal budget, why spend ...

Its a fair point. I was ready to enter this year and didnt care where I finished. I just wanted to give my car a punt and would be interesting to see where I cam against other rwd 2l road cars on semis. You pool together your own competition The reason I didnt do it as entry, tryes, brakes and travel meant that I could go hire a car and drive Zandvoort using FF points cheaper My point is for the money to just enter and try and get the most out of your setup its going to cost the same as a pretty cool 3-4wk OS holiday

[Nee-san]

I could very well be wrong..but think about it...no way the Cyber Evo weighs 800kgs. NO WAY! But your point is correct..you can get away with cars that have good OE brakes for a lot longer when you are ripping weight out of them.

I will just repeat, I will masturbate with a cheese grater in public on film if the Cyber Evo weights 800kgs If it weighs > +/-35kgs of 1000kgs they have done an amazing job

Best not to listen to a word I say...BUT...there is plenty of reasons why without significant improvements in downforce you wont achieve shorther stopping distances on a std pressed steel mass manufactured car by going for bigger rotors (increase in braking force) and bigger calipers with more piston area (increase in braking force) and racey pads (increase in braking force)

I suspect you could know more then me about this stuff and its a baited question...so will try to explain my view.

In saloons like most of us punt, they weigh a lot, have good hp and have limited grip. Under brakes its all about tyres and how grippy they are and suspension: how good it is at controlling the pitch of the car under brakes and ride the bumps when the shocks are under compression.

You get braking force/torque from pad compounds, rotor diameter and piston area. All this works to help slow a car to the point that the tyres dont lock up. Tyre grip is again just friction so given a certain tyre grip, the only thing that is ever going to increase friction (ie grip under braking) is an increase in the normal load. You increase the normal load on a car/tyre with downforce. So the only way to increase the normal load on a tyre is to increase downforce which gives the tyre more grip. If the tyre has more grip than you can use additional braking force.

I agree that track cars need brake upgrades, but since Skylines have pretty good gear std, its mostly about thermal management and trying to avoid brake fade. NOT increasing braking capacity as it will just result in bitey brakes that lock up too easily.

You often increase thermal efficiency with better pads, fluid..then rotor diameter and pad surface area. By going to better pads you normally increase braking force...which is the reason why many AP/Alcon calipers that use 365mm rotors etc have less piston area then std Nissan gear. Because the assumption is they will run good pads with higher friction coefficient + bigger rotors which also gives increase in braking force...when it comes to the piston area they are smaller then std calipers. This is an attempt to stop waaaaay toooo much front brake bias, because std its all pretty good. Its all about stopping fade so they increase rotor diam, increase pad area and reduce the piston area to maintain essentially the std braking bias whilst adding loads of thermal capacity

LOL, probably makes no sense...I best read this again in the morning when I have not had two bottles of red, beers and watched The Thing (Both 1982 and 2011 )

No way is the Cyber Evo even close to 800kg, you are right in assuming approximately 1000kg.

And reading this thread it is crazy how misunderstood braking systems are, It's always funny to see people turn up with cars that are low weight or stockish in power, running 12 pot brembo's they bought off a Lamborghini "Superxyzasdnkllasdn" - I loled.

[Nee-san]

Agree that downforce needs speed to help. If you look at open wheelers and their brake pedal pressure trace on data you will see that when they first jump on the brakes they are trying to put their foot through the floor, as the speed washes off the tyre grip afforded to them drops off as the downforce drops off with speed so they drop the pedal pressure otherwise they will lock brakes. Saloon cars are the same but to a lesser extent as they only have downforce (normal load N) measured in the tens of kilograms rather than hundreds of kgs. (to go from weight to force you multiply by gravity - 9.81; so 10kgs is 98.1 Newtons)

Re ABS, I am not convinced if its a good thing or a bad thing. Personally I cant stop cars for shit and am always locking brakes and ruining tyres. I suspect late model cars with faster processors etc in their ABS would stop quicker using it....not sure where a GTR sits in stopping distances.

But yeh, the mechanics/dynamics of cars braking is pretty interesting. This is the theory behind what I am trying to say...

And this is why braking will always be shorter if you dont lock brakes

Essentially when a tyre is rolling there is no slip between the tyre surface and ground so is referred to as static friction. When a tyre locks then you have slip between the two surfaces so you have kinetic friction. As kinetic friction is lower then static friction then you will always have less grip with a tyre locked.

Thank you, Thank you I haven't seen that beautiful diagram for YEARS !

[fatz]

i still recon stock brakes will be fine for one lap

[Marlin]

i still recon stock brakes will be fine for one lap

Is that why you take two minutes for a minute lap?

[Marlin]

Its a fair point. I was ready to enter this year and didnt care where I finished. I just wanted to give my car a punt and would be interesting to see where I cam against other rwd 2l road cars on semis. You pool together your own competition The reason I didnt do it as entry, tryes, brakes and travel meant that I could go hire a car and drive Zandvoort using FF points cheaper My point is for the money to just enter and try and get the most out of your setup its going to cost the same as a pretty cool 3-4wk OS holiday

^ This

But like I say, if you've an excess of cash.......

The entry list will always be packed, despite the dubious value or GFC. And aint that cool!?!

[Duncan]

It is cool.

Any event where a hammerhead silvia can run is cool

[fatz]

i think the last lap of ec i did was a 2 minute flat.... so yea i guess so (stock r31 gxe though)

still recon it would be apples

decent pads, correct master cylinder

maybe some brembos with some soft pads would be a winner (but they weigh a good 5kgs more a side)

one hot lap no faken dramas you only need to brake 7 times in a lap at ec and only 2 of those are real stops

decent race brakes your looking at 2 laps to bring up to temp with shit feel until then by which time your rubber is tost

save a spare 20kgs of rotating mass as well compared to your super dooper 8 piston alwesomness

perfect for super crap one lap machines

now a car running multiple laps different story

[benm]

^like

[Marlin]

Sorry. Fell asleep. Line 2, word 1, "decent".

My bad.

Build it and I will believe. Until then. LIES! lol hehe

[fatz]

superlap people love the big brakes

or maybe they use there cars for things other than superlap which involves more than one lap

but if they went smaller brakes they could save themselves one "poofta-tenth" of a second a lap

lol

[Marlin]

Haha. Rate it!