DBA Rotor Comparison

[marcusus]

Brake fluid $10 = most noticeable benefit
Brake pads ~$200 = next best benefit
Slotted rotors $600 = least noticeable benefit

A bit of a trend there!

I'm puzzled why you'd be willing to spend near $600 on a set of rotors that will do the same job for you as <$300 regular rotors. Save your money or spend it elsewhere. Also if you've still got enough thickness in the old ones, it seems wasteful to chuck them in the recycle bin when a machine should only cost less than $100 for all four.

Disposable income

[Charlie Brown]

An old thread I know but I thought some may be interested in a report on the DBA slotted street rotors.

I have been running these rotors since November 2009.

17 track days (Wakefield, Oran Park and Phillip Island), 55,000 daily drive kilometres, one machine job and six sets of pads later they finally cracked and gave up the ghost at this month’s Club track day.

I heavily abused them at the track, as can be seen by the number of pad sets I’ve been through, and I think they did well to last this long.

As others have said in earlier post, you won’t notice any difference using slotted rotors on the street, bar that initial application in the wet.

At the track, and the reason I bought them in the first place, they did noticeably dispel the gasses from the pads and therefore were worth the extra money over a standard rotor.

Next up I’ll probably use the Club Series 4000 T3, if they make it for the NC.

[manga_blue]

Brake fluid $10 = most noticeable benefit
Brake pads ~$200 = next best benefit
Slotted rotors $600 = least noticeable benefit

A bit of a trend there!

I'm puzzled why you'd be willing to spend near $600 on a set of rotors that will do the same job for you as <$300 regular rotors. Save your money or spend it elsewhere. Also if you've still got enough thickness in the old ones, it seems wasteful to chuck them in the recycle bin when a machine should only cost less than $100 for all four.

Hmm, just noticed this load of absolute rubbish from Guran, of all people.

First up, you need to recognise that cars need rotors and that they're consumable items. It's not about benefit and it's not discretionary expenditure. Choosing not to spend any money on rotors usually means a choice of whether you want to be able to drive your car at all or not.

Second point is around quality, safety and price. I've no idea where you could find slotted rotors for an MX5 for $600. My last set of DBA 4000 slotted fronts cost me around $200. The same DBA set before that cost $180 and lasted 3 or 4 very hard years and worked brilliantly to the end. A hasty purchase of lesser brand rotors this year cost me $220 and they lasted one day and could have killed me if I hadn't been lucky enough to spot the cracks.

The third point is around slotted vs unslotted. There's a small benefit in wet performance for slotted disks. I don't really notice it on the track because after 1/4 lap they're so bloody hot that water's not an issue. Most of my driving life in my area involves twisting coast and mountain roads with a fair degree of rain and fog. I really appreciate the first up bite of slotteds vs plains in my area. For me the slots are about safety. In any case you only pay a small premium, if any, for slots in a quality brand.

Please note that all my points relate to fronts. Rears do so little in comparison that almost anything round will do.

[timk]

If you could get a standard friction ring & alloy hats for the NB8B brakes it might be a fair weight saving? The Wilwood kit saves a fair bit of weight.

EDIT: I need to learn to read!!

[greenMachine]

If you could get a standard friction ring & alloy hats for the NB8B brakes it might be a fair weight saving? The Wilwood kit saves a fair bit of weight.

EDIT: I need to learn to read!!

Big weight saving (4-5kgs a corner iirc) . Pity they cannot be engineered for road use ...

[Dan]

DD in the wet, I'd prefer slotted rotors, they disperse water too so you have a better chance of "emergency stopping".

Seriously? You are worried your brakes holding you up trying to stop in the wet?

[marcusus]

Well, I've had the new rotors (and pads) on for a bit now, and it was certainly a big improvement over the factory rotors and the EBC greens, even when they're cold and in the wet (as it has been here in Perth recently). I'm yet to give them a go on the track as I'm waiting for my clutch/flywheel to still bed in properly, but I daresay I'll get quite an improvement when I hit the track in them.

Given Phil's assessment of how long his have lasted and how heavily he's hammered them, I think these will be quite suitable for my uses.

[Guran]

I've ended up going the 4000 series T3 for the fronts, and the T2's for the rear. Price wise was great from Race Brakes Sydney. They were able to do the 4000 series T3 fronts for $160 each, and the T2 rears for $115. Shipping to Perth was $42, so all up it was $592. The cheapest I could find locally was $730, and that didn't even include shipping! Stupid expensive State that it is...

@manga_blue ... I was quoting marcusus when I mentioned $600 for slotted rotors . In my limited experience with slotted rotors, I don't think they're worth that. I haven't used them on my NA6. However I did have two sets on my MINI Cooper S several years ago. Never had a problem with wet braking or initial bight before or after fitting them. However they were very harsh on the pads; they ate the front pads (Bendix Ultimates) after about three track days, and I ended up with metal on metal for the drive home from Wakefield Park. I can understand how they benefit outgassing from hot pads but it does seem to come at the cost of higher wear on pads. So keep a close eye on pad thickness if you're using slotted rotors.

[manga_blue]

Ah yes, Bendix Ultimates. I've had a few sets of those. In fact they're on the ute now as the only pads I can find that can safely get me down Clyde Mountain towing the MX5. You could well have a jaded view of slotted rotors after them.

High pad wear + very high rotor wear + unbelievable amount of dust + better than average stopping and fade resistance.

Most good pads for our cars work much better on slotteds than those.

[project.r.racing]

If you are using ultimates at the track, then don't blame the rotors for them wearing quickly. The have a low friction rating at a low temp. Something like 0.45 @ 300c? and it is down near 0.40 at almost 400c.

http://www.bendix.com.au/content/bendix ... ultimate-1

I have been using TRW pad (something like 0.52-0.54 @ 600c-650c) with RDA slotted rotors for about 6ish years. Done about 75,000km street driving and forgot the amount of motorkhanas, dirt sprints, khanacrosses and track days I have done. The rotors are down to about 20.5mm from the original 22.0mm, and the pads have lost about 30-40% on the fronts.

[marcusus]

Time to dig up an old thread of mine!

So here's something interesting... I've gotten Mania to do a brake pad change, and they've informed me that my DBAs have had it. They've only had Hawk HP+ pads on them, and both the pads and the rotors were installed 30,000km ago, and as per the original posts, about 3 years ago. Driving wise has only been track days once every few months and daily to/from work without pushing hard.

I don't doubt that the rotors are gone. My question is whether or not this seems like a very short lifespan for this combination of brake pads and rotors, given the type of usage they've gone through?

[RileyR]

I just bought this same pad and rotor combo. I hope I get more than 30,000km out of them!

Sent from my SM-G900I using Tapatalk

[StillIC]

I don't doubt that the rotors are gone. My question is whether or not this seems like a very short lifespan for this combination of brake pads and rotors, given the type of usage they've gone through?

I had DBA slotted rotors and EBC Greenstuff pads on my Celica, used as a daily and for hillclimbs and a few supersprints. What you quote is about what I found with this combo, and the pads and rotors both wore out together. That is, the slots were almost gone from the rotor due to wear when the pads were completely worn.

On my MX5 I am finding that the Carbotech XP8 pad wear is greater than the slotted DBA rotor wear, but hard to judge how much at the moment.

[marcusus]

Interesting to hear that I'm not the only one. Mania changed over to the generic solid discs, and I've now put QFM A1RM on as the pads. At least if these rotors die at 30,000km I won't feel so bad about it!

[madjak]

On my MX5 I am finding that the Carbotech XP8 pad wear is greater than the slotted DBA rotor wear, but hard to judge how much at the moment.

I found with slotted rotors I went through pads very quickly, and the also the rotors themselves. The pads lasted less than 8 months and expired on my last event of the season. I wasn't planning on buying new pads and rotors every year so I upgraded to 11.75" Wilwoods and the wear rate is much much slower. The replacement rotors are very cheap so the upgrade will pay for itself in a few years. Pad wear is next to nothing now, which I think is due to the temp the brakes are operating at as well as the non-slotted smoother rotors.

I don't think there is any need for slotted rotors.. who needs good braking in the wet anyhow? I'm certainly not braking limited in the wet, it's definitely a traction limitation.