It sure is. The one and only Jose.

Nice to see you are still around Tim.

I just never believed the "groove" hype. Holes are for poseurs too. Just give me a good rotor and leave the fashion accessories for the belly buttons of very hot young ladies.

I keep intending on updating that website, but never get around to it. ahem.

 

What's the rear kit cost? Is there a link?

 

it was from a group buy, and the link for the gb is no longer in teh gb section but you may find it via searching for rs/rz brake group buy

 

How much lighter is the Precision two-piece rear rotors compared to the 99+ one-piece rears?

 

sorry, didnt weight them :-(

 

I'll weigh my stock 99's if someone can chime in with the weights of the precision fronts. BTW, those hats look damn good.

Tim

 

well, if i feel like being a nice dood i may take the rim off one of these days and weigh the rotors....but not for a while, i like seeing the car all together :-)

 

That's cool guys, just trying to get an idea for the cost/benefit ratio -- the Precision rotors are significantly more expensive than the OEM 99 rotors.

 

Good news for me:
drove all day today with the new brakes, they kick ***

Bad news for you:
since i have a dedicated track car now this car will not see the track so I cant comment on brake fade and track level high speed braking conditions

 

These are the weights for the Precision rotors assembled:

Fronts....16.0 lbs even

Rears.....11.6 lbs

 

thanks 7racer

 

Thanks!

For comparison, OEM 93-95 front rotors weigh ~15 lbs. I don't think the small weight savings over the 99+ rotors are worth the cost -- for me, anyway. Others obviously have to make their own price/performance judgement.

 

I think the Mazda RZ rear rotors are in the neighborhood of 12.5 lbs each. I weighed them at one point, but I don't know where I wrote the weights down. The 12.5 lbs is from memory and might be wrong.

-Max

 

The '99 front rotors are larger in diameter and significantly thicker then the '93-'95s, and therefore have much better heat capacity. Here is a pic that artowar took comparing the two (OE RZ/RS spec and OE 93-95):



While weight is always a concern of course, the reason for brakes are to stop the car - and it does so by converting forward motion into heat. With the greater mass to absorb the heat, combined with the curved, directional cooling vanes of the Precision rotors (the OEs are straight), the RZ/RS spec are much more effective beyond simple street driving.

The only place I can think of that the extra 1lb would hurt you is in drag racing perhaps? I'm assuming there is plenty of time for cool down between passes.

Another way of looking at - my CWR SMIC is significantly heavier then my stock IC, but the benefits far outweigh the weight gains. And a fair comparison would really be that of the OE RZ/RS spec rotors and the Precision two-piece RZ/RS spec rotors. The Precision rotors should be lighter then the OEs, considering the hats (centers) are machined fron aircraft quality aluminum.

In the end, the GB pricing for the two piece rotors ended up to be roughly $90/rotor more then OE RZ/RS rotors for the front, and roughly $60/rotor more for the rears.

 

dclin: I know how brakes work, but I couldn't find a weight for the 99 rotors. My post was trying to determine the weight differences between the 99 OEM and the Precision 2-piece. I'll spend more money if there is a significant performance improvement, but I won't spend a lot more just to eke out a small (unnoticeable?) improvement. I'm always trying to hit the edge of diminishing returns.

 

looks great!!!

i with rynberg on the diminishing return.

whats the price tag on those?

 

well, the upfront cost is a lot but 'supposedly' you come out even in the end since you buy only outer part of the rotor every time you need to replace them. its the hat that costs the $$ upfront since it has to be fabbed.

 

Damian, I understand that as well. However, this is very likely a case of it taking several years for the benefit to kick in.

I fully understand the benefits of two-piece rotors and I think it's worth it for the fronts, but I don't think the rears are worth it. Just my opinion and I didn't mean to clog up the thread. The brakes look great and I'm sure they'll function very well on the street.

 

i agreew with you rynberg,...really its about looks, not savings :-)

 

Hehhee Tim you need me to translate your RX-7 mags? ;-)

-Kib

 

This may be a dumb question, but do the Precision rotors fit with normal 93-95 calipers?

 

nope, these are made to fit the bigger rs/rz calipers

 

We organized the RZ/RS GB a la carte - meaning you only needed to order what you wanted. Some ordered just the fronts, some ordered just the rears, some ordered just rotors, etc.

To give you an idea of pricing though, the complete kit - RZ/RS big brakes FRONT AND REAR with the nice two-piece rotors - came out to around $2000 (give or take a little, depending on options choosen).

Compare that with most big brake kits going for around $2000 + for just the front, then you can see that the GB pricing was a steal.

But as rynberg alludes to though - 'big brakes' are not for everyone. If you plan on just driving around on the streets, NONE of the big brake kits available is going to be of benefit to you. Same as my IC analogy. The stock IC is perfectly fine for putting around on the street. Save your money and put it else where, as that it's been said over and over again, the stock 93-95 brakes are fine for the street.

For those that actually need the 'big brakes' though (whether they do the odd track event, or just likes upgrading to something 'better', the RZ/RS GB was down right wicked (if a bit slow to close hehe).

 

Oh, I fully plan up upgrading to either the full 99 brakes or the Stoptech/99 combination (stock brakes can't handle the track use with streetable pads anymore). My only point was the price/performance difference between the one-piece 99 rotors and the two piece Precision rotors of the same size.

And yes, the group buy you put together was great, I wish I could have taken part.

 

The other thing is that it may be harder to get the RZ replacements than it is to get the custom replacements. I ordered my RZ rear rotors when Mazdaspeed was still selling non-stock parts to the public. They don't do that anymore, so I would have to find a different source for the rotors.

I don't think Precision has any spare rotors in stock, but I am sure they could be convinced to make more, or you could use one of the "standard size" replacements that wouldn't need to be custom made. Wilwood makes a $40 rotor that is very, very close to the right size (for the rears) -- I would definitely use them in a pinch. Perhaps there are other "standard sized" rotors that would work in a pinch as front replacements, too.

-Max