Front Brakes - Suspension question
 

Is it a 2-piston caliper design or 4-piston?

If it is 2-piston any ideas how to upgrade to 4-piston calipers?

Is the suspension tight enough for track use or it needs an upgrade?

It's a single piston calipers front and rear, the front caliper has the larger piston.

They are common "sliding" type calipers.

To upgrade will require a new caliper, I doubt that anyone makes either a direct replacement caliper or brake kit for the RX-8 yet.

But they will.

By the way, a single piston caliper does not mean cheap or poor brakes. BMW uses this design along with the majority of cars on the road.

A good 4 piston fixed caliper will cost around $600 all by itself. A kit can be anywhere from $2000-$5000, dependent if it's front only and the exact design.

And considering the RX-8 leads its class in braking... why replace them anyway?

Exactly!

And with the large rotors and light weight, fade should not be a problem. Only if the pads or fluid are not up to hard use, but $100 will solve that problem.

Re: Front Brakes - Supsension question
 

if you're thinking (competitive) autocross, you'll certainly need to bias the comprimise the setup far far more toward a high G-load setup, along with a much twitchier alignment (also hard on tyres)... no question.

for track use of course

unless you're going crazy and planning on running it in a heavily modified class on road courses (where speeds get high enough you have to seriously worry about pad wear over one race), you won't need to.

aggressive pads, good ducting, better fluid, maybe stainless brake lines (more maintenance), and frequent refinishing/replacing your rotors as they get used up will probably be sufficient.

I agree for road use they must be excellent brakes. I am thinking of taking the Rx-8 to the track though and you need better brakes there for sure.

Take my Jetta for example. It's got excellent brakes for road use but in the track they are useless.

If the Rx-8 cannot be competitive on the track with $2000 of mods (front brakes and suspension) then it's not the car for me.

Well, I have a friend with a Prelude. I drove it it's got excellent brakes in stock setup. He just put NSX calipers in the front, took it to the track and he saw a significant improvement.

agsid, you can't compare things like that.

The RX-8 has a great pad swept area to ton ratio. What makes a brake system adequate is rotor size, caliper piston size, fluid type, pad type and tires. Plus suspension also.

The Jetta's brakes like most cars are sized for low-heat braking. They have small rotors.

The RX-8 has a huge rotor for it's weight.

All you will need is pads and fluid to be just fine on the track.

Put simply the RX-8 brakes come ready for duty.

Just to give you some comparisons, the 350Z at 250lbs. more has the same rotors. The BMW M3 at 450lbs. more only has slightly larger rotors. Both cars have a lower swept area to ton ratio.

Normally, most cars come with "undersized" brakes for track duty, the RX-8 is not one of those cars.

Prelude doesn't have near the stopping distance the RX-8 does.

The RX-8's brakes are one of the best things about the car... to compare the simplicity in design to a Jetta, is a poor comparison.

The RX-8's brakes will be fine for track use in my opinion... you can waste your money to save yourself a foot or two of distance but I don't see much point, because as pointed out, it's not going to reduce fade much more.

Feel free to waste the cash on the brakes... I'd put my money elsewhere.

I'll take it to the track first and then I'll see how competitve it is. I am not going to upgrade brakes or suspension unless I have to.

That's the wise way to go;)

One suggestion for the brakes: IF you find them lacking, first upgrade the fluid and pads. You may find this does the trick and save yourself some money.

I was about to say, all of this bench-racing and guessing at this point won't help you determine what you need to improve the brakes, until you put in on track a couple of times.

I'm sure that you can upgrade the brakes. What it takes, whether it is worth the cost and other compromises, etc., can only be determined once you've put it on track with your setup.

---jps

True.

But I thought it's good idea to discuss this issue before I spend $45-50k CAD buying this car.

Take my Mazda Miata for another example. Stock, it's got excellent brakes for the track - in the Spec Miata race series, they use stock brakes with race pads. No problems. The RX-8 should do even better with the size rotors it's got. Try it out and see if they're insufficient first!

Regards,
Gordon

As already mentioned, you may want to replace the pads for heavy track use. The stock pads are meant for street use and will heat up quickly to allow good breaking under normal driving. If you are planning to race the car or drive it hard for a long period of time on a road course you will need higher temp pads. Swapping on a set of Hawk Blacks or Performance Friction 93 compound pads will mostlikely be all you need to do. Hopefully PF will make a set of pads for the 8. They stopped making pads for the 3rd gen a few years a go.


Mike

Agisd, are you talking about Kostas aka ouzo?

For all those saying that the brakes should be good enough for the track, have you ever done some hard laps on track with multiple hard stops from 200-220km/hr to 80-60 km/hr? Just becuase the 8 can stop on a dime on the street a few times means absolutely nothing on a big track. Like others said, we will not know until someone does take it to the track but I suspect that the pads and fluid will have to be upgraded. SS lines won't hurt either. With the upgraded pads, the question of them chewing up the stock rotor comes up.

I might consider giving my rotors the cryogenic treatment.
http://www.frozenrotors.com/frozen101.shtml

Regarding the suspension, unless we're talking Porsche, Corvette, etc I don't think the 8 suspension is tight enough for track duty. But then again that is a personal choice, will the "tighter" coilover suspension make you a better driver? I doubt it. Will it make the car more enjoyable during daily driving? Most likely. The stock suspension on the Prelude is decent, it was voted the top fwd handling car under $30K I think at its time but after I put on my Tein HA coilover setup, it's like night and day.

Yeah, for a living actually.

Well we agreed on fluid and pads.. I feel great now. :p

Yes, I am talking about Kostas. I was at Shannonville with the Preludes the other day (I took the class with Ian Law).

I agree with you, most likely the 8 will need new suspension, brake pads and brake fluid. If I buy it I won't touch anything for a year and then we'll see.

CS or GT?

Gonna move this thread to the Tires/Brakes/Suspension forum(Yes we have one now).
:D

First, just because a brake setup can last a race doesn't mean that it's performance cannot be improved upon. Second, a 2,000 lb race car with low power (some 130hp) doesn't need big brakes, because it doesn't need to scrub off much speed in a braking zone. So it's not going to need more braking than the street car.

A 3,000 lb car with some 250 hp is not going to be the same thing.

---jps

Probably CS.. I'd love the sunroof but I'm not sure if I can fit with a helmet on.

the sunroof opens on the outside. they should have the same headroom.

i would go for the GT (dunno yet about sunroof)...