Brake upgrade

[Lukejjwhite]

Hiya I have 09 Lexus is220d was wondering if there was some sort of brake upgrade for it. Not needed I know but mine don't seem to be doing much got drilled discs but seem to be worse and noisy. Heard gs300 fits is250 would this be the same for 220 ? 

 

Thankyou Luke. 

[Linas.P]

Yes - GS300 brakes would fit IS220d, I am just not sure they would be "upgrade", generally it should be the same brakes between 250/220. What is considered an upgrade are the brakes from IS350 or GS350. The only thing to check is whenever you have solid or vented rear disks, on IS250 I know that for 2009 these would be vented, but IS220d I am not sure.

That said if your brakes are not doing much, why do you think this is necessary an "upgrade issue", do your brakes actually works as they suppose to? Maybe your callipers are stuck or you have some other issues related with the braking system? I am not sure throwing "bigger brakes" would solve the issue. Overall, I think that you need to define what you mean by "don't seem to be doing much" and fix the faults first before looking for upgrade. To be fair I was never very happy with the brake performance on IS250, but it was not the case that car does no brake, it was simply the case that front disks were wearing like crazy. Obviously it was automatic car, but front disks would not even last 2 sets of pads... so 30k-40k miles for the disks are pretty poor and they dusted a lot. As such fitting bigger brakes from GS300 or IS350 is kind of upgrade on maintenance, they last longer and dust less, but they do not provide "more braking power". I guess they fade less quickly, so if you braking repeatedly (like on the track), then IS350 brakes would work better for longer, but just by themselves in one time they would not help your braking distance - the key part here are tyres and nothing else.

Besides drilled disks not suppose to improve braking power, if anything they should be worse for power (less surface) and as you have experienced noisier. Drilled disks are mostly for show on normal cars and on racing cars like rally, they suppose to help to braking when disks are wet or dirty i.e. rally car gone over the puddle of mud and that mud is between disk and pad and if it has nowhere to escape, then car won't brake, but when there are holes the dirt and steam can escape and it allows for pads to make contact with disk. In very old racing cars there was as well issue with "pads gassing" when brakes were overheating, this gas was again preventing good contact and thus drilled disks were used. But as you can see - for normal car under normal circumstances this is never an issue... so drilled brakes are just for show. 

[NemesisUK]

4 hours ago, Lukejjwhite said:

Hiya I have 09 Lexus is220d was wondering if there was some sort of brake upgrade for it. Not needed I know but mine don't seem to be doing much got drilled discs but seem to be worse and noisy. Heard gs300 fits is250 would this be the same for 220 ? 

 

Thankyou Luke. 

Can you lock up the wheels (invoke ABS) when you do an emergency stop?

Bigger brakes will not give better stopping power, that depends as much on tyre grip. What bigger brakes give is greater heat dispersion and more consistent repeated stops, not something one usually encounters on road driving.

Drilled discs do tend to be noisier than non-drilled but they also disperse water better and can offer better initial bite. They wouldn't be fitted if they didn't offer a benefit.

I'd be tempted to get brakes overhauled first to be sure they are functioning as designed, Lexus spent lots of money/man-hours developing them in combination with the car.

[J Henderson]

Luke, you can swap the front brakes for those from a GS450h - or any other Lexus models that feature those same ADVICS 4-piston calipers.

They're a direct bolt-on replacement with just a small piece of the dust shield needing to be trimmed to accommodate them on an IS.

Pair them with a set of GS450h discs & pads and you have a significant upgrade. Furthermore, the GS calipers are a monobloc design which makes them maintenance-free with none of the anxiety that they'll eventually start sticking and seizing up.

1 hour ago, NemesisUK said:

Lexus spent lots of money/man-hours developing them in combination with the car.

Maybe, but I agree with Linas in that they feel kind of weak, even in perfect working order. The front disc diameter is only the same size as a 1st-gen IS200, which weighs over 200kg less.

Anyway, I'm curious to know what you guys mean when you say braking/stopping "power" doesn't get increased with bigger brakes?

If you mean stopping distance then yes I would agree, but for me, braking power is most definitely increased. The brakes are more powerful and require less physical effort (on the brake pedal) to achieve the same level of retardation.

 

[NemesisUK]

26 minutes ago, J Henderson said:

The brakes are more powerful and require less physical effort (on the brake pedal) to achieve the same level of retardation.

 

Be careful larger pistons and calipers might require a servo upgrade as well.

I can see the appeal of changing to more a impressive looking brake setup but it rarely achieves a performance upgrade (unless coupled with other upgrades and then usually just for track performance) plus the big elephant in the room, insurance. Make sure your insurer is ok with the modification.

[ColinBarber]

59 minutes ago, J Henderson said:

Anyway, I'm curious to know what you guys mean when you say braking/stopping "power" doesn't get increased with bigger brakes?

If your brakes, and your leg, can cause the wheels to lock up at speed then you have overcome the maximum frictional forces of the tyres - having bigger brakes that can generate more force isn't going to make any difference because you have already generated the maximum needed.

Now, if you want harder braking power for less leg input then upgrading to larger brakes can help, as can changing the pads for different friction material or upping the brake booster assistance - but this doesn't improve your stopping distance, just the effort required by your leg in pressing down the pedal. Larger brakes often perform worse when cold as there is more mass to get up to optimum operating temperature - so that initial cold bite isn't as good.

 

If you track, tow or often come down very steep and long mountains then bigger brakes help because they dissipate heat better, avoiding brake fade.