dbasteve

Endless MA45 for endurance RS4-2 or DS2500 for track days DS3000, RS14 for more serious super sprints and rally Hawk HT10's were also very good for a high initial bite on tarmac The above will be noisy on the road and not ideal. Shop around and don't pay too much. Road - Hmmm, if you bed them in properly NAO's are very good. Low noise, low wear. I'm doing some work on these and carbon ceramics at the moment.

Hi Hadouken, I started a new thread to explain in more detail. This probably isn't the best thread in hindsight. What's good? I don't sell anything so I'm not pushing any cart here. For many many years sintered metal pads dominated in hard core racing. PFC, SBS, Hawk, etc Then came the carbon metallics. Ferodo, Endless, Pagid, Proj Mu, etc And the carbon/aramid fibre (Kevlar?) . Carbotech, Hawk, EBC, etc (FYI Kevlar is a registered brand name of the DuPont company. Some pad manufacturers use the Dupont material but not all). NAO (Non Asbestos Organic) pads are becoming more popular for road use. With a ceramic base the dust and wear is low with good friction properties. Too many brands to mention but I'll name a couple. Bendix, Fed Mogal Wagner, Ferodo, most OEM's and many rebadged brands. Carbon metallics are generally a good place to start for Skylines. DS2500 and RS4-2 were popular. A safe option but not specifically the best for everyone.

So why is normal and hot friction characteristics important? Depending on the material elements used in a compound the friction lining will behave differently at different temperatures. This has many positives when deciding on a material that best suits the application and driving style. Torque Response or Initial bite is one of the key characteristics considered at low temperatures. If your starting an event or routine and your brake temperature is low (approx 100 C) then the friction level most likely will be different to when the brake temp is 200, 300, 400, 500, etc. The SAE J2522 or AK Master dyno test has a routine to collect this data when developing a product. I've attached an example chart of some random test data off a dyno. The initial torque response is clear to see and so is the peak effectiveness. So if I wanted to run for lead position at the first corner with cold brakes (100 C) and stabilise at 0.5 mu to achieve good modulation I'd probably lean towards the red compound. If I had warmed up to 250 C then I may go for the black compound. If I were in a lighter car or going argy bargy then the blue or yellow may be the better choice. Choosing a compound based on max friction is not as simple as most egberts make it out to be nor is it the best option in many applications. Too much friction at the wrong time can flat spot tyres or put you on the grass (hopefully), initiate ABS modulation which governs braking performance or too little affects confidence and competitiveness.

Yep, Best not to hit anything hard with a hammer. If they don't come out with a light tap then unbolt the hub assembly and find a press. A simple hand operated press is good, so you don't apply too much pressure. Its only the high points of the spline that are engaged so unless rust has really taken over you'll be fine. Missileman (Mike) you're right. Heavy handed effort with a hammer can hob (brinnell) the bearing race. A tap tap versus bang bang. lol

It's not a legal requirement in Australia to conduct the J661 test or print on the backing plates.......yet. There is little legislation in Australia to control the after market. I suggest you ask the reseller for the hot and cold friction coefficients and see if he chokes.

Brake Terminology, Technical and Trends Hi Guy's, I have a favourite saying "No matter how much you polish a turd, its still a turd". I've been away from the brake industry for a while but some things never change. The polishing of products to convince people to buy. I thought it might be a good idea to share some technical terms and some of the science behind brakes so you can compare apples for apples as they truely are behind the glossy marketing and verbal diarrhea. I have no intention of naming or bagging out any brands or manufacturers (unless they piss me off) so lets keep it clean and educational. Brake Pads I’ve been fortunate enough to have been factory trained with a couple of friction lining manufacturers around the world. NAO, Sintered metal, carbon metallic and low metal high carbon pads. One thing is for sure, its personal. Every driver has a different perception of what is good braking. Why we have so many arguments ;-) The most basic of identifiers for brake lining characteristics is the good old SAE J661 hot and normal (cold) friction coefficient test which is the codes stamped on the pad backing plate. They will look like; EF, FF, GF, GG etc printed in between a whole heap of numbers. The other numbers refer to batch codes and friction formula used. The USA and Europe require this detail to be marked on the pads to comply to various legislations. SAE J661 - Friction identifiers. Normal Friction , Hot Friction is the order of the codes E = 0.25 to 0.35 mu F = 0.35 to 0.45 mu G = 0.45 to 0.55 mu H = 0.55 and above The USA (mainly Ca and Wa) have introduced a hazardous materials legislation called Chapter 70.285 RCW which I have had the joy of participating in for compliance. They've identified a number of ingredients in brake linings that are polluting water ways and making their fish glow in the dark. Copper reductions is a major topic in the USA as this is one of the main offenders. As with the bans on asbestos many years ago, the same appears to be happening with Copper. Another topic is the European R90 compliance. Its been around for a long while but is gaining more focus locally. Possibly because sales guys have run out of things to talk about. R90 is all about driving comfort. NHV (Noise, Vibration, Harshness) is the focus. This is directed towards regular road pads of which most OEM's are compliant and aftermarket no so much. Key metrics for measuring performance; I'll add some more detail about these soon. Torque response (initial bite) Peak effectiveness (peak friction @ time/temp/pressure) Release speed (speed to fully retract) Modulation factor (compressibility and a combo of above) Pad wear A good driver will understand these metrics and will be able to adjust his methods to suit in order to achieve the desired outcome whether it be sprints, endurance, off road, or just regular road driving. I hope this terminology helps. Please feel free to ask any questions. No such thing as a dumb question. Cheers DBASteve

The wheel studs fitted in the hub. You need to buy OEM or matched aftermarket studs designed for your hub. Typically Unbrako brand are the best. They supply OEM. The head has a spline on it which stops the stud from turning when you tighten the wheel nuts. I just ran a quick search in this forum and found this tutorial. Best if you try to line up the head spline before pulling through.

No Worries and good luck. Give everything a good ol soak in WD40 a day or more before. Take the pads out first.

I’ve been fortunate enough to have been factory trained with a couple of friction lining manufacturers around the world. Sintered metal, carbon metallic and low metal high carbon pads. One thing is for sure, its personal. Every driver has a different perception of what is good braking. The most basic of identifiers for brake lining characteristics is the good old SAE J661 hot and normal (cold) friction coefficient test which is the codes stamped on the pad backing plate. They will look like; EF, FF, GF, GG etc Normal , Hot E = 0.25 to 0.35 mu F = 0.35 to 0.45 mu G = 0.45 to 0.55 mu H = 0.55 and above Key metrics for measuring performance; Torque response (initial bite) Peak effectiveness (peak friction @ time/temp/pressure) Release speed (speed to fully retract) Modulation factor (compressibility and a combo of above) Pad wear A good driver will understand these metrics and will be able to adjust his methods to suit in order to achieve the desired outcome whether it be sprints, endurance, off road, etc. I haven’t discussed the technical aspects of ducks nuts, shit hot or awesome with the companies but I am in contact weekly. I hope this terminology helps. Cheers

Thanks Duncan

Studs are cheap and easy to replace. Those in the picture look like they have advanced corrosion and aren't safe. Assuming you can get some wheel nuts on don't leave it too long.

I guess you've harvested the potatoes already. Hi Mate, Please either re-machine those discs or get new ones (your pads will thank you), rebuild the calipers (seal kit), replace the studs and clean the rust off those hubs and inside the disc hat. You should then have a safe ride. Cheers

Cool, Tell I'm here if he wants a chat about thermodynamics and brakes

Hi niZmO, Hmmm! I designed "The Paw" back in 2002 and it's still sold globally. So yup! There's a lot more to it than the pillar vane though. Two piece rotors. There are some AP and Brembo mount hole versions in the range. No reference to the GReddy kits though. It's possible if there was enough demand to justify a production run or you may be lucky and the hole positions match the AP or Brembo replacements. Need more info. All the math (stress/shear loads) is done on the DBA rotors as an assembly. Mods and specials really should follow the same process. I always look at risk v dollar$.

Kind of but not really! Hi Guy's, It's been a long while since I was here last so I'm kind of a newbie again. All things brake design and R&D at DBA is what I do now and did many years ago. We have some cool projects in progress and this forum has always been a good source of feedback. I hope to have some interesting discussions in the future. Sorry I'm not the guy for product enquiries or sales. There are good people here for that. Happy to help with any tech questions or help sort out any issues. I'll be stalking the brakes section. Cheers, Steve