Has anyone read/heard anything about Rotora brakes?

They make a big brake kits for the 03-05 S-type R and 04-05 XJRs.

Rotora Brakes - Rotora Brakes

12 piston caliper with 380mm/15" rotors! That is a lot of breaking surface on a very large rotor.

 

Aren't the stock ones 14"?

 

They'd be Brembo 365mm / 14.4" and they don't appear to need to be any bigger. You hear of STRs having trouble braking? No.

If those others are heavier won't they spoil the handling somewhat?

 

I was actually thinking of going with a lighter rotor. Found a place that will make a 2 piece rotor for 550/set

 

Since I have a regular S-type, with standard brakes, I have been considering some sort of upgrade. STR's Brembos should be good enough for most street applications, but if you give your car a good workout on winding hilly roads, or quick stops from higher speeds, or take it on the track, it is always desirable to have more stopping power during repeated braking.

12 pot calipers with 3 pairs of pads and the large rotors seems to be a pretty good combination for lots of stopping power on a heavy car like the S-type.

They are a bit out of my price range, but are less expensive than the equivalent Brembo upgrade.

 

Ah I thought you had a STR already.

 

You make it sound like Brembos won't handle the winding hilly roads etc. You're kidding, right?

 

I realize it would be a lot of work to put Brembo's or some other larger brakes on earlier non Brembo S-Types. Plus new wheels. - 18" or larger.

I am already running into some unique issues with my slow going LS3 swap that uses 2009 Pontiac G8 electrical in the S-type. One of the issues is with integrating GM ABS into my car, so I am already working on a hub swap to a higher pulse reluctor. The hubs I plan on using have a 5 X 4.5" bolt circle pattern rather than the jag's 5 X 108 pattern. Plus, these hubs have a larger flange offset that will let me use other more common/cost effective rotors and spacings so I should be able to move away from the S-type unique wheels that use a 60mm offset. (ET60), Or for the STR, the 42ET or 49ET used on the 19" factory 19 X 8 wheels. I just have to be careful not to add too much scrub to the suspension geometry. This change is going to be very slow going, so I have plenty of time to be sure I maintain proper suspension geometries.

So other than the cost, Why not put high performance brakes on the car?

The non-practical side of me is thinking about flaring the wheel-wells so I can put some real tread on the road. Something in the range of 275s in the front.

 

By all means put whatever you like on your car but I don't understand why you said what you did about the STR's Brembos. They're more than ample for almost every use, including those winding hilly roads you mentioned, aren't they?

The STR has them mounted on strengthened suspension, so you may want to strengthen yours even more, especially if you're going larger & heavier when everything will be bad about that as regards unsprung mass and the need for even stronger suspension parts..

 

Please go back and read what I've written so far. I have not made any comments regarding how good or bad STR brakes work. My comments are in reference to S-types in general. Even my thread states S-type, not STR.
I believe you are drawing conclusions that I am stating that STR brakes aren't good.

The only reference I've made so far to STRs is that the Rotora kit is listed for 03-05 STRs. Since I do not have a STR, I have no idea how well the STR Brembo's work. I do know that putting new STR brembos on a 2000 S-type is expensive and a lot of work.

I have a friend that took his 2005 STR on the track at Sears Point and he did complain that his brakes started fading after about 20 minutes of track time.
He ended upgrading his front rotors and changed to Hawk pads. He stated that the car did much better the next time on the track. Therefore I could state that the calipers are good, but the rotors and pads are not track worthy, but this is still no comparison to just driving hard on country roads. My brother purchased a 2011 Corvette Z06 a few month back and he has already replaced the front rotors and pads after his first track day, with the same complaint as my friend with the STR.

I believe that the STR's Brembo caliper weighs about 5.5 lbs. Looks like the 12 pot Rotora caliper weighs in just under 9 lbs (4050 grams) - About a 3 lb more - Is that a lot? Will 3 lbs more on the suspension degrade the handling of the car?

So back to my original question: Has anyone read/heard or have any experience with Rotora brakes?

 

3lbs is a lot on unsprung weight. I have no experience with them, but they have to be better than what you currently have!

 

I weighed my stock 2000 S-type caliper and mounting bracket. 10.2 lbs with 1/2 worn pads. STR brembo's would be a 5-1/2 lb weight reduction. The 12 pot Rotora's would weight about a pound less than Stock 2000 S-type calipers. I wonder how much more/less, the 365 mm STR rotors weigh than the the stock S-type 12", 17 lb 12 oz rotors? Looks like 15" diameter 2-piece Rotora rotors weight around 15 lbs.

The Rotora big brake kit would reduce the unsprung weight of my 2000 S-Type by around 4 lbs per front wheel. Probably a wash versus a STR with Brembos.

If one is trying to reduce unsprung weight, you can go with lighter larger diameter rims. Correct me if I am wrong, but don't lower profile tires in larger diameters weigh less than smaller diameter higher profile tires? Example a 245/45ZR17 tire weighs about 29 lbs. A 245/40ZR/18 weighs about 25 lbs.

So based on your comments, I need to look at my planned suspension changes from a systematic basis, besides only worrying about what brakes I put on the car. Less unsprung weight = Good. Proper suspension geometry = Good. More stopping power = Good!

 

Yes!! Also, tires make a huge difference in not only cornering, but in braking. If you exceed the limit of grip (acceleration or deceleration) of your tires, then no amount of brake kit will help you stop quicker. Usually brake kits have 2 piece rotors that help shave weight as well. What gets me is unless you can get one of those kits cheaper than what I saw on the website, it might be cheaper to get a STR setup.

 

Am I reading this correctly you are putting an LS3 into an S type?

 

I quoted your own words about the STR's brakes above. And responded about them. Later you've moved away from the STR but it was the quoted stuff I was responding to.

Yes you'll have to consider everything (brakes & suspension) as a whole. That's how they're originally designed. That's why I pointed out that the STR has extra-strength parts so if you're heading towards or past its performance then you'd probably want to follow the kinds of things they did. Not much point, for example, having extra stopping ability that shears a wishbone because it wasn't uprated.

If you're doing serious track work then you know that for that you expect to discard rotors etc and use different pads etc plus brake fluid. The winding hilly roads you cited are not the same as hard track use.

 

Sounds like a cool project. I personally would have started with an str with a broken trans or engine and then swapped the ls3 in. As the guys mentioned the str does have heavier duty suspension parts and decent brakes. In either case you'd want to do something about the lack of limited slip diff. Also the '03 up cars suspension feels superior to the older s types in my opinion after having both. I'm not sure what the changed but the newer cars feel much different.

 

Major suspension changes were made as part of the redesign 2002.5 (2003 USA). Quite hard to retrofit as all manner of things were changed.

 

My take on the thread:

STR Brembo's would be slightly better than the Rotera setup, but more difficult and likely more expensive. Either choice would be beneficial to you non-STR S-type OEM setup - less weight and better braking.

Therefore seems to me the Rotera would be a good choice if you can get some type of user feedback. Unlikely anyone on this board would have that, I haven't seen or heard anyone discuss the brand on here.

I think a motor swap build thread is in order....can you oblige us?

 

There's one already, sorry not sure the title but if you look for the member's posts (click Search, then choose Advanced in case you didn't know) it'll rapidly be apparent. He's got a really interesting (but challenging) project going on.

 

Shame on me! I should have looked.

Thanks jagV8