ATR brake setup pros and cons + master cylinder confusion

[Max]

I'm considering doing the upgrade to the ATR brake caliper and as i understand it there are 2 approaches:

1 - Use the ATR caliper with the Prelude carriers, 282mm discs and pads

2 - Use the ATR caliper with the ATR carriers, 300mm discs and pads

I know that the 300mm discs are also thicker than the 282mm so overall better for heat management if you are going on track but i assume there is still a good amount of braking performance to be had with the ATR calipers on Prelude discs and pads.

Both are supposedly a direct bolt on, just fit, bleed and away you go, but what i dont understand is if the caliper is bolting directly onto the existing mounting point in both cases how exactly does that work with the 282mm discs, or have i got this all wrong?

Also i read that if you dont have a 1 inch master cylinder the first inch of pedal travel is vague, but that cars equipped with ABS do have a 1 inch master so dont have this issue?

[ek9sid]

The carrier is what gives you the extra distance for the caliper fitment. If you want to use the 282 setup then you'd bolt the atr calipers onto the prelude carriers. The atr carriers will bolt on to the hub perfectly and then the calipers bolt on to them.

If that's what you were asking lol

[Max]

Ahhhhhh im a moron, the carriers are what bolt onto the hub not the other way around, it all makes sense now, no idea what gave me that idea

Still confused about the master cylinder situation though, can anyone confirm what the deal is with that from experience?

[vanzep]

yes go for the 1" prelude master cylinder - it does make a difference (approx 12% over 15/16" mc)

[Scott560]

There isn't much you can do about the master cylinder I don't think.

The ATR one will not mount to the prelude booster and I don't think the pipe outputs are in the right place. I couldn't even find a new 5th gen MC or aftermarket MC for 5th gen. In the end I had to rebuild using OEM seals/pistons from amayama.

Out of rebuilding callipers twice, different pads twice, many re-bleeds, different discs etc, only rebuilding the MC gave me the good braking coupled with some rock hard pads.

It's true the brakes will feel a little worse like for like with ATR callipers.

I don't think there is much benefit to just doing the ATR callipers without the carriers. The extra disc diameter and width is key to the improved braking performance and cooling. I was pretty happy with the track day performance using ds2500 pads on the ATR setup. They just kept going. Not mega hard braking performance, but you could get many laps out of them. I moved to harder pads (PBS Race) and the braking now feels amazing and is pretty stonking braking performance but only for 2 or 3 laps.

If you are not tracking it - perhaps just try some harder pads, it will make the pedal feel better and give you a big increase in braking effect. Makes extra heat but if your overheating on the road your doing it wrong in my eyes.

I only fitted the bigger brakes after unsatisfactory track days on standard setup

[Max]

yes go for the 1" prelude master cylinder - it does make a difference (approx 12% over 15/16" mc)

Which preludes have the 1" master cylinder?

[Max]

There isn't much you can do about the master cylinder I don't think.

The ATR one will not mount to the prelude booster and I don't think the pipe outputs are in the right place. I couldn't even find a new 5th gen MC or aftermarket MC for 5th gen. In the end I had to rebuild using OEM seals/pistons from amayama.

Out of rebuilding callipers twice, different pads twice, many re-bleeds, different discs etc, only rebuilding the MC gave me the good braking coupled with some rock hard pads.

It's true the brakes will feel a little worse like for like with ATR callipers.

I don't think there is much benefit to just doing the ATR callipers without the carriers. The extra disc diameter and width is key to the improved braking performance and cooling. I was pretty happy with the track day performance using ds2500 pads on the ATR setup. They just kept going. Not mega hard braking performance, but you could get many laps out of them. I moved to harder pads (PBS Race) and the braking now feels amazing and is pretty stonking braking performance but only for 2 or 3 laps.

If you are not tracking it - perhaps just try some harder pads, it will make the pedal feel better and give you a big increase in braking effect. Makes extra heat but if your overheating on the road your doing it wrong in my eyes.

I only fitted the bigger brakes after unsatisfactory track days on standard setup

I dont think there is anything wrong with my current brakes tbh, they're not amazing but they're not crap either, i dont plan on tracking the car it just seemed like a fun little upgrade project so im just trying to get my head around it.

Im confused by your reply though, people say you need a 1" master cylinder but you're saying there isnt one that fits?

[K30DPC]

I'm running ATR setup for a while. It was plug and play. I'm not 100% sure if my calipers are from ATR or not (some civics using same size discs and 2 pot calipers), but I remember I had an issue to bleed them properly as nipples are on the bottom if you fit them correctly. I mean if you fit right caliper to right side of the car. You can swap sides and then they still fit and nipples gonna be in highest point, but there are 2 postons in the caliper and smaller one should be leading one.

Not sure about master. I had no issue but I have 4gen with ABS so 1 inch master was fitted by factory.
IMHO Scott meant it is hard to get hold of one from prelude instead of there isn't any to fit prelude.

Another thing to mention is brake balance. Bigger discs shouldn't affect it that much but 2 pot calipers will. I never overheated 282mm setup, and succeeded to overheat 300mm with no probs. I don't think my driving habits changed after new setup was fitted. Also I don't believe it was due to discs/pads as I'm still using the same setup. Bigger brakes simply do more hard work. Problem has gone when 290mm rear discs were fitted.
This may not be the case if you gentle with your car

Also my 15" wheels didn't fit ATR brakes.

[Scott560]

Just to add:

The ATR 300mm setup fits under 16inch standard 5th gen wheels, but only just. If you have wheel weights more than a 2mm high on the inside, they'll probably catch. Its pretty tight clearance wise. Be sure to do a spin of the wheel to check. No way 15inch will fit with 300mm.

I believe the 1inch vs 15/16th issue is a 4th gen issue where there were cars with and without ABS. This doesn't apply to 2.2 5th gens because they all had the largest available MC (which i think is 15/16th). I don't think there is a 1 inch 5th gen MC.

I don't know what a 1inch 4th gen MC looks like compared to a 5th Gen, but when I compare ATR MC to 5th Gen MC, the interface to the booster is different. Whether you can swap out the whole ATR booster I couldn't say, pipes probably in the wrong place too. I couldn't find any replacement 5th gen MC at all (new), and rebuilt my old one. This gave the best improvement in pedal feel.

There is no orientation issue with ATR twin pot callipers on the prelude. They are the same fitment as the prelude (At the front of the car/hub, leading calliper position), so the bleed nipples are on top.

I believe it is the legend twin pots which are trailing, so when fitting to a lude in the leading position , in order to keep the smaller/larger piston in the right position (to stop squeal), the bleed nipples are upside down which makes bleeding a little more involved (undo 1 calliper bolt, flip up and bleed whilst 'chocking' the piston so it doesn't pop out).

If you want better braking for the road, try a different pad first, along with tyres. For road use, higher friction pads give better braking, at the expense of heat build up. You shouldn't be overheating on the road though. I only went for the bigger setup to help with heat on track days. That kind of braking should never be seen on the road. Truth be told, the PBS track/race pads have a marginally improvement over the first couple of braking applications. Cold weather can make them feel normal, but in the most for a nice sunday drive they feel like concrete and that's great. They overheat after 3 hard laps at bedford (full circuit) but that's fine, getting a bit frantic at that point.

[Merlin]

I have the ATR calipers, carriers and discs on my 5th gen, you are better off using the ATR discs as they are thicker. As said, it's a plug and play upgrade. Don't worry about brake boosters and master cylinders, all 4th and 5th gen Preludes with ABS brakes come with the 1" MC.

viewtopic.php?t=263&start=210

Old Prelude single piston caliper and 282 x 23mm disc


New ATR dual piston caliper and 300 x 28mm disc


With the wheel on


The brakes feel very good and was very easy to swap over.