Terrafirma Wavy Vented Front Disks - Do They Actually Clear Mud?

[DiscoClay]

For any of you who've actually used these disks, can you speak to their ability to clear mud and generally to any other attributes (balance, durability, wear, etc)? These appear to be stock rotors that have been cut; the waves are not cut symmetrically with the cast-in webbing... which makes me question the balance of these.

I've used drilled rotors before and while I never really noticed "accelerated wear" from dirt/mud plugging the holes, i also generally hosed down the undercarriage after any serious 'collection'. But I have seen plenty of cracks around the holes on track cars (Porsche used to be the only main-stream cross drilled rotors with cast-in bosses for the cross-drilling.. maybe thats common now but it used to be rare).

Brake Disc Front (pair) Wavy Vented - LR017952WCDG - Terrafirma | Rimmer Bros

Order your Brake Disc Front (pair) Wavy Vented - LR017952WCDG - Terrafirma ⛽ Low prices and fast, worldwide delivery ✈ British car experts ♚ Call ☎ 01522 568000 or ☎ 1-855-746-2767

rimmerbros.com

Product Description

Drilled, Grooved & Vented

Terrafirma wavy cross drilled and grooved brake discs are made to the same high standards as the CDG brake discs. Wavy edges clear mud and debris from within the caliper and they look awesome too!

Cross drilling and grooves offer increased bite from cold and help force gasses and dust out from between the pad and disc. The Terrafirma WCDG discs are painted black on all non-friction surfaces for corrosion resistance when fitted to the vehicle.
Specifications and additional product information
Defender 1983-2006 - All Models from VIN LA930456 on - Quantity Required - 1
Defender 2007-2016 - All Models from VIN 9A777777 on - Quantity Required - 1
Discovery 1 - All Models - Quantity Required - 1
Range Rover Classic - All Models from VIN GA399973 on - Quantity Required - 1

 

[Tugela]

While not specifically this model, I did install a pair of slotted/drilled rotors on the rear of my RRC because Atlantic British had them on sale when it was time for replacement. I can't say I noticed any difference in performance that I wouldn't have otherwise achieved from solid rotors and pads. The fact that they were new was likely a bigger factor in braking performance improvement than their design. Plus it was the rear, so less contribution to stopping relative to the fronts. At any rate, my trusted local indie tech with 40 years experience gave me shit for choosing them, saying they were superfluous and there was no real gain to be had from them on this vehicle. They weren't any worse than solid rotors.

 

[ERover82]

Venting in general makes a difference in extreme braking conditions. The drillings tend to get clogged with mud, making them useless. I'm skeptical of wave design rotors since OEMs producing off-road vehicles, who have teams of actual engineers, don't appear to utilize them. Also I've never seen mud be an issue with these brake systems anyways.

 

[Greg_M]

Interesting question. Always thought it a useless gimmick but try to find a mountain bike rotor that isn't waved. Marketing or "actual engineers"?

 

[DiscoClay]

While not specifically this model, I did install a pair of slotted/drilled rotors

The biggest thing you'll notice with drilled rotors is *noise*. They can be quite chatty.

But yeah I am specifically wondering about the *vented* wavies. They look like they'd be out of balance.

 

[rovercanus]

I've used drilled and slotted rotors far a while now and never had issues with them clogging with mud to make them useless. The factory heat shields on the other hand get taken off at the first brake job.

 

[rovercanus]

And for what it's worth, we are talking about Terrafirma so it's probably junk anyway.

 

[discostew]

What’s the reasoning behind making them wavy on that outside edge? I don’t get that.

 

[ERover82]

What’s the reasoning behind making them wavy on that outside edge? I don’t get that.

Because it looks sick bro.

 

[ERover82]

Interesting question. Always thought it a useless gimmick but try to find a mountain bike rotor that isn't waved. Marketing or "actual engineers"?

Can't sell a mtb without a nice floral design on those highly visible rotors.

 

[4Runner]

I have used crossdrilled and slotted rotors for a couple decades at least. On the Toyotas, I noticed a difference in braking and in lifespan without warping. Toyota uses a lot of front brake bias on 4Runners and Tacos. Hell even Tundras. So now to Discos and Classics. I use them due to the mountain passes despite using engine braking, it’s not always enough. The scalloping around the outside is a weight thing verses mass to dissipate the heat. Not worth it at all until you are in a very high performance environment or on mountain bikes where performance and weight matter more than not. Personally, I try really avoid Chinese parts for automobiles if at all possible. I would try even harder not to use them for anything brake related. That is just my preference.

 

[DiscoClay]

This thread is all over the place

4runner makes an interesting point about mass v. heat.

Mass is pretty handy for soaking up heat...but surface area (+airflow) is even handier for getting rid of it.

Why do you guys dislike terrafirma?

I only have experience with their axle flanges and they seemed to hold up pretty well.

 

[discostew]

Because it looks sick bro.

Yeah, but do it ride good?

 

[terryjm1]

On my manual trans D1s I don’t see a real need for drilled / slotted. I did upgrade to standard D90 front vented rotors because I needed to replace both the calipers and rotors anyway. The cost to go with D90 parts was almost the same.

I frequently travel up and down long steep grades and downshifting works wonderful to keep the rotors from over heating. On a manual trans, I really don’t believe drilled/slotted is needed unless you just don’t want to downshift.

However, on an automatic in the same driving conditions, I can see the benefit. Downshifting helps a lot but it is not nearly as effective as the manual trans.

As far as the terrafirma wavy ones, seems a bit gimmicky to me. If you want vented, standard D90 stuff is relatively cheap and works well.

I have overheated brake rotors in my TR7 when doing “spirited” driving. It will scare the poop out of you. You can stand on the brake pedal and almost no braking happens. I have replaced the standard skinny rotors and tiny brake calipers with larger vented rotors and much larger caliper/pads. No issues since then.

My opinion is if you are frequently experiencing warped rotors or have had issues with brake fade, you should consider such an upgrade. If not, I don’t see the point.

On terrafirma in general, I think most of the negativity comes from their coil springs that have a history of sagging.

 

[Blue]

I used the DBA Gold vented front rotors on my 2004 D2 and they lasted over 90K miles and 7 years, which is a hell of a lot longer (and a hell of a lot cheaper) than the OEM rotors are lasting on my LR4 (already looking at replacing the LR4 front rotors after 2 years and 32k miles).

 

[pinkytoe69]

I used the DBA Gold vented front rotors on my 2004 D2 and they lasted over 90K miles and 7 years, which is a hell of a lot longer (and a hell of a lot cheaper) than the OEM rotors are lasting on my LR4 (already looking at replacing the LR4 front rotors after 2 years and 32k miles).

LR4 weighs quite a bit more right?

 

[4Runner]

This thread is all over the place

4runner makes an interesting point about mass v. heat.

Mass is pretty handy for soaking up heat...but surface area (+airflow) is even handier for getting rid of it.

Why do you guys dislike terrafirma?

I only have experience with their axle flanges and they seemed to hold up pretty well.

A great way to increase the surface area of the circumference is to scallop the rotor or add some others pattern to it. It really starts to add up when you have a 14” or 16 “ brake rotor. Not quite as much as the rotor gets smaller like a lot of production vehicles have. For me the China thing is complicated, has almost nothing to do with the people. I know there are quality products that come out of China, ( I am using an IPhone for this ). But generally if something is way cheaper than the other thing, then something was sacrificed. Quality, materials, or labor. And usually at the expense of intellectual property theft of the company selling the same or better product for more money. This is probably a rant for a different thread but luckily at this point in my life I can try and make a difference with my choices. For me, I don’t just draw the line at auto parts. Are parts any better morally speaking from the EU or the UAE? I don’t know. Just my opinion.

 

[discostew]

LR4 weighs quite a bit more right?

I think it does weigh more but those LR4 stock rotors are becoming a real problem. The center portion that has the lug holes in it is too thin. When the rotors get hot they warp. If the wheels aren’t torqued properly they warp and pulsate. I’m looking for some rotors that the center hub section is thicker. I just ordered a set from RockAuto that look thicker. I’m going to measure when I get a chance.

 

[Blue]

LR4 weighs quite a bit more right?

Yes but my 2004 was certainly no lightweight with winch, bumpers, sliders, etc.

 

[Blue]

I think it does weigh more but those LR4 stock rotors are becoming a real problem. The center portion that has the lug holes in it is too thin. When the rotors get hot they warp. If the wheels aren’t torqued properly they warp and pulsate. I’m looking for some rotors that the center hub section is thicker. I just ordered a set from RockAuto that look thicker. I’m going to measure when I get a chance.

I warped the set of non-OEM rotors that were new on my LR4 when I picked it up used a couple years ago. I had bad pulsating from the front end when pressing the brake pedal. My local mechanic replaced them with new OEM rotors and they've been fine, just short-lived. At my last oil change about 5,000 miles ago he said it's almost time for new rotors again. They've lasted 2 years and about 32k miles. My mechanic only uses OEM. At just under a grand for the front axle it's a bit much for only 32k miles of use.