Brakes

[Fulcrum2000]

I know its been covered to death but excuse the maybe ape like questions here. Supras are superb but in my opinion the one area where they could be better is braking and with that in mind:

 

1) Are all Pads equal, I know with calipers it can only apply certain pressure etc but assumedly high end pads makes significant difference to OEM? Anyone know which is best?

2) I have JDMs all round at the mo on my TT and want to go UK, anyone have a set and do they just plug and play? So if I change all round the bias remains perfect? I know they arent any better than JDMs but dont overheat so quickly. I have 18 inch Avons I assume they have decent clearance?

3) I have seen Supras with LS400 4 pots on, are these essentially the same brake system as I can get these new, anyone have any experience/knowledge of this?

[Guest Budz86]

No all pads are not equal. Best way to explain would be look to look at the EBC range; they are colour coded depending on what your use is (road, fast road, track sprint, track endurance etc). Shows how many different compounds there can be from just one manufacturer. Pads choice is key as an endurance race pad on a road car would be dangerous really, and a road pad on track lasts about 5 mins.

 

With regards to calipers, the UK spec brakes are larger, have more pistons and work better in terms of stopping force applied to pad/disk as well as heat dissipation so they are superior to the jspec ones in every way other than cost. As for brake bias, I used to run UKs up front with poterfield RS4 pads and OEM discs and jspecs OEM rears with cheap Pagid pads. Never had a problem stopping and didn't really get fade either. Used to keep a couple spare set of rears in the garage though as they lasted about 6 months lol

 

 

[Scooter]

Jspecs are a different design and their sliding pins and Pistons seem to be more prone to seizing, possible due to the higher heat they might see.

 

Stock discs and updated pads and fluid is the standard advice regardless of uk or spec callipers.

 

I once spent about £350 for a set of cw race (j-spec) pads, these were awesome even on track, but expensive and dusty, but I would recommend them.

 

I have jspecs on both my tt's with uk's in the garage that I really must fit bit like the lsd I haven't got around to it!

 

Cw fast road pads with uk's all suit most people, all but the hardcore users where the choice of really high performance pads for uk's is limited.

 

Fully working jspecs with race pads and good fluid won't look as good but 100% will do the job, but this still requires quite some money throwing at them, so if yours aren't perfect and more 'refurb ready' it's often more cost effective (Ie isn't much more on top) to bin them and to upgrade to the uk's.

[Fulcrum2000]

Thats good advice once again Scooter I feel like the Supra should have had a bit more stopping power out of the factory and it does seem all the big brake kits actually dont improve it much bizarrely. Now I'm nearly full BPU (still have to find someone to key in the BC to get the last bit of boost but close) I do find it a bit of a freight train effect in that it picks up superbly but then slowing to feed back into traffic is a bit of a chore, its the exact opposite in my 535D, it picks up nicely but could be a smidge faster but its brakes are so over the top it makes up for it in all late braking situations and they never seem to fade either. I'm a similar age to you so I love a blat but I dont want to end up hanging out of a tree as some grotesque bauble so I dont go crazy like I used toso maybe JSpecs will cut the mustard with CW Pads all round.

 

As final question and perhaps one I should also have asked Chris whilst I was on with him is discs, are the standard discs the best you can get on JSpec or have you gone ventilated or third party? I've had over 40 cars in my time and I think the Supras discs are the 'smoothest' I have ever seen which is surely a tad counter productive? I put ventilateds on one of my MR2s though and they acted like a cheese grater....

[Dnk]

Was always impressed with how well my UK spec stopped on OE discs and pads, just braided lines

and Motul RBF 600/660 brake fluid

[Fulcrum2000]

Maybe I've been spoiled by the massive Beemer anchors and its me and I think its been well established that JSPecs are largely similar in performance to UK Spec but fade much faster so hopefully the CW pads will be just the thing. I've noticed a slight whistling when going along under twenty sometimes recently which I suspect is a brake slightly sticking (it does it in and out of gear coasting so obviously brakes or running gear so changing the pads all round will hopefully get rid of that annoyance too. Do you think ventilated discs help Dnk?

[Dnk]

Not sure how they are similar in performance to be honest, mkiv's i've driven with the smaller brakes on

didn't seem even close to my UK set up, unless of course they were not at 100%

 

 

Vented is always going to help with cooling the disc so the way to go really

[Fulcrum2000]

I got this from the thread on here with all the testing which showed both kinds of brakes to be equal but JSPecs to fade out much quicker excuse my ignorance if thats not true, I'm on my third Supra and as far as I know they've all had JSPecs. I'm always looking for UKs but do they actually have much better performance then? The same thread indicated all the big brake kits were either the same or worse than standard as well which I was surprised at as it was on my list to put brembos or similar on the old girl but at 4k or so and no improvement thats clearly not going to happen if its true!

[Scooter]

They are better and will feel better, but at 60 mph on a normal drive with an emergency stop the stopping distance won't be much if any different. In fact good tyres and jspecs will beat poor tyres and uk's, as if you plant the brake pedal abs will kick in ie the brakes overpower the tyres grips so you get maximum retardation regardless of the braking setup if abs is activated, better tyres will allow harder braking before the abs kicks in.

 

They can feel better as less force on the pedal my be necessary, but this is 'feel' over actual performance gain.

 

The main issue with jspec brakes is that a Supra can be used hard so every few secs may be on the brakes, in this scenario (fast road/track work) heat builds up fast and doesn't get the chance to dissipate, so then pads and fluids get hot. Pads have a temperature range where they retain their coefficient of friction, after which the lose it and you get brake 'fade' ( ranges from not good to scary) fluid can expand or even boil up and then brakes really fade badly.

 

You have to look at it as a package/system and match/balance things.

 

Braided lines, good fluid uk's and cw fast road pads will be good apart from hard track work Imo.

[Fulcrum2000]

Yes I would agree, I think I will keep looking for UK brakes and sling these CW pads in and see whats what Scooter, you've been very interesting on this. I have to figure out if UK calipers fit under my 18 Avons too. As to tyres, I actually chose the ones with the best brake distance testing, Pirellis on the front and Falkens on the rear, according to the tests you cant beat this on a Supe but I am wondering if going to Pilots or something is better? Not sure how these tyres could come out better on a test if they are though.

[Style]

 

The MK4 Supra had the best standard brakes on the market until the Carrera GT came along in 2004 I believe. It held the record for shortest stopping distance from 70mph for about 12 years. Granted tech has come a long way since then, but the UK setup wasn't to be snuffed at in it's heyday

[Fulcrum2000]

I think it must be me then, I've always been an incredibly late braker and maybe its just perception, but when you make your tyre choice to maximise braking potential I guess you think the car will stop on a dime and mine has had new pads, discs, fluid and lines so you cant get more serviced than that! I will keep an eye out for UK ones and uprate my pads in the JSpecs in the meantime

[Fulcrum2000]

Can anyone confirm if the 'UK Brakes' we all refer to are the same as LS400, according to many sources they are. It would follow as they are on a sister company car, are 4 pot and look identical to UK Supra brakes.

[Scooter]

They aren't no (look closely at the calipers and you'll see visual differences), they are the same in that they are 4 pistons and don't have sliders like Jspecs, but they don't use the same disks or pads as uk's, so are often seen as a cheaper way to upgrade from Jpsecs. Uk's are found on Celica GT4's but no lexus's.

 

The supra doesn't have that over servo'd bite that you can get in even say a Pug 206 1.1! Sometimes the effort we have to put in effects are perception of how well the brakes are working. If you activate the abs, then all you can improve is the effort that takes through the pedal, less effort required will definitely mean most people think the brakes are better, it certainly might be a more pleasurable setup, it's sort of personal I spose?