Jump to content
SAU Community

Recommended Posts

He's talking R32, so, to quote;

BRAKES AND SUSPENSION

• Front Endless slotted and ventilated rotors

• Front - Std Nissan four-piston callipers w/EBC green pads

• Rear - Std Nissan twin-piston callipers w/Bendix pads

• Rear Std Nissan ventilated rotors

I'm telling ya, they'll last half a lap. 33/34 Brembo would do a lap with the right options. Cyber Emo runs std Brembo calipers with upgraded rotors etc. but an Evo will always be lighter than a GTR, by a long shot.

How anyone is supposed to do proper testing to get a car to work properly, with brakes that just last a lap and are as inconsistant as hell has got me phucked.

Next.

  • Replies 54
  • Created
  • Last Reply

Top Posters In This Topic

Top Posters In This Topic

Posted Images

BK i have a similar history to u mate ive raced motorcross /supercross 4 bout 15 years and did some road bike racing and i gave superlap a shot my car is making 400kwatw have big brakes and all that ikeya has available on my car i thought my car was ready to kick butt on street tyres pfftdreamer) never drove a car on the race track wow man what a buzz i got top ten in clubsprint nothing special but had a ball i say give it a shot with your set up i would vcam it bigger brakes and the suspension and do alot of track days time in the seat mate i did a r32 as well

hopefully see you next superlap

The 443kw on the R33 is what Tilbrook in Adelaide calculated for engine kW. The R33 makes around 325 - 330 wheel Kw consistently. Sorry for not addig that. The 520+ kw at wheels on the R32 should be around 700 engine kW ? Correct me if I'm wrong ?

when this post-72724-0-57316400-1323434776_thumb.jpg = this post-72724-0-78713100-1323434860_thumb.jpg u really need these post-72724-0-94795000-1323435028_thumb.jpg and Roy just wondering what downforce has to do with braking on saloon (full bodied cars)? And i really cant agree with brake upgrades not being required... Weight and speed will show weaknesses in inferior brakes

And BK why does the R33 loose 120KW and the R32 looses 180KW? Shouldn't they loose the same amount of power? Its not a % its actual power loss.... i would think a 60kw (100hp) loss on dyno with 4wd car would be more like it.

cyber evo 340kwatw weighs around 800kgs

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

and Roy just wondering what downforce has to do with braking on saloon (full bodied cars)? And i really cant agree with brake upgrades not being required... Weight and speed will show weaknesses in inferior brakes

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 :) )

I must admit most of my expeirence is with GTR's and when an owner actually "uses" the brakes correcty to stop/slow down as quickly as possible they should be activating the ABS... This is basically guarenteeing that the car is giving its all. I tell whoever wants to listen that Tyres or make that tyre grip hugely affects how well u scrub speed. Better brakes help you do it faster and repeatedly. Down force on the other hand requires speed to function, but we are trying to slow down... Also under heavy braking the cars nose dives down and the weight transfers to the front tyres. You obviously have know a fair bit and i also am just giving my own veiws be they what other consider right or wrong... Cheers

ABS is just going to throw the car off balance on corner entry, and when you are shooting for the fastest possible single lap the last thing you would want is the car trying to shake itself to pieces as you are trying to tip it into a corner.

ABS also increases stopping distance in my experience, as you have gone for too much pedal and the ABS isn't giving you the full brake force.

My opinion is if the ABS is going off in the dry than you have crap tyres or you are just stomping on the pedal with all your might

In summary - ABS is great for enduro cars or targa cars that need to run on the same tyre for long periods, for SuperLap/sprints etc it is just adding weight.

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...

surfboard_wax_friction_defs.gif

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

frictiongraph.JPG

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.

And BK why does the R33 loose 120KW and the R32 looses 180KW? Shouldn't they loose the same amount of power? Its not a % its actual power loss.... i would think a 60kw (100hp) loss on dyno with 4wd car would be more like it.

I as always under the impression that GTRs lost around the 25% mark from engine to wheels on average and that the losses actually increase the higher the horsepower. Your saying you reckon 330kW at wheels is under 400kW engine ?

Tein Monoflex have also left the UK friday for the R32.

Yes they did :unsure:

And, it is just a poor choice of events for most entrants. Strange rules that don't work with any other events, very little lap time per $$$, and very expensive to get to the front of the field.

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 10 year's racing budget on getting to the top 5? There are much better ways to get track time if you want more than 30 laps for your year's budget.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now



  • Similar Content

  • Latest Posts

    • I came here to note that is a zener diode too base on the info there. Based on that, I'd also be suspicious that replacing it, and it's likely to do the same. A lot of use cases will see it used as either voltage protection, or to create a cheap but relatively stable fixed voltage supply. That would mean it has seen more voltage than it should, and has gone into voltage melt down. If there is something else in the circuit dumping out higher than it should voltages, that needs to be found too. It's quite likely they're trying to use the Zener to limit the voltage that is hitting through to the transistor beside it, so what ever goes to the zener is likely a signal, and they're using the transistor in that circuit to amplify it. Especially as it seems they've also got a capacitor across the zener. Looks like there is meant to be something "noisy" to that zener, and what ever it was, had a melt down. Looking at that picture, it also looks like there's some solder joints that really need redoing, and it might be worth having the whole board properly inspected.  Unfortunately, without being able to stick a multimeter on it, and start tracing it all out, I'm pretty much at a loss now to help. I don't even believe I have a climate control board from an R33 around here to pull apart and see if any of the circuit appears similar to give some ideas.
    • Nah - but you won't find anything on dismantling the seats in any such thing anyway.
    • Could be. Could also be that they sit around broken more. To be fair, you almost never see one driving around. I see more R chassis GTRs than the Renault ones.
    • Yeah. Nah. This is why I said My bold for my double emphasis. We're not talking about cars tuned to the edge of det here. We're talking about normal cars. Flame propagation speed and the amount of energy required to ignite the fuel are not significant factors when running at 1500-4000 rpm, and medium to light loads, like nearly every car on the road (except twin cab utes which are driven at 6k and 100% load all the time). There is no shortage of ignition energy available in any petrol engine. If there was, we'd all be in deep shit. The calorific value, on a volume basis, is significantly different, between 98 and 91, and that turns up immediately in consumption numbers. You can see the signal easily if you control for the other variables well enough, and/or collect enough stats. As to not seeing any benefit - we had a couple of EF and EL Falcons in the company fleet back in the late 90s and early 2000s. The EEC IV ECU in those things was particularly good at adding in timing as soon as knock headroom improved, which typically came from putting in some 95 or 98. The responsiveness and power improved noticeably, and the fuel consumption dropped considerably, just from going to 95. Less delta from there to 98 - almost not noticeable, compared to the big differences seen between 91 and 95. Way back in the day, when supermarkets first started selling fuel from their own stations, I did thousands of km in FNQ in a small Toyota. I can't remember if it was a Starlet or an early Yaris. Anyway - the supermarket servos were bringing in cheap fuel from Indonesia, and the other servos were still using locally refined gear. The fuel consumption was typically at least 5%, often as much as 8% worse on the Indo shit, presumably because they had a lot more oxygenated component in the brew, and were probably barely meeting the octane spec. Around the same time or maybe a bit later (like 25 years ago), I could tell the difference between Shell 98 and BP 98, and typically preferred to only use Shell then because the Skyline ran so much better on it. Years later I found the realtionship between them had swapped, as a consequence of yet more refinery closures. So I've only used BP 98 since. Although, I must say that I could not fault the odd tank of United 98 that I've run. It's probably the same stuff. It is also very important to remember that these findings are often dependent on region. With most of the refineries in Oz now dead, there's less variability in local stuff, and he majority of our fuels are not even refined here any more anyway. It probably depends more on which SE Asian refinery is currently cheapest to operate.
    • You don't have an R34 service manual for the body do you? Have found plenty for the engine and drivetrain but nothing else
×
×
  • Create New...