viperbob

Pagid makes pads with specific compounds for Porsche. Don't let colors fool you. The PMNA sport pads are green, but are pretty close to an RS14. RS29s have much better initial bite (better than Orange, not as good as a black) and have better longevity. Mated with an RS29 rear or even better a RS14, you have a nice balanced setup. If you are going from PCCBs and have the larger rear rotors, the RS29 f/r works pretty well.

RJFabCab

Chris,

I can't comment on PFCs since I've never run them.

Let's assume that your trailbraking goals are 1) to carry more speed into and through a corner and 2) to get the car to rotate more easily.

You mention a hindrance, but what exactly are your issues with trailbraking? Are you having trouble getting the car to rotate? Or, is it rotating too much as you enter the corner and trail the brake? There are many variables here and an attempt at the solution really depends on the problem.

You are an experienced driver. Your car is aggressively aligned with a comp suspension and slicks and with RS14s I would guess that you're not over rotating.

Going with RS19/14 f/r would lessen your front bias potentially decreasing your ability to rotate the car holding everything else equal. One might suggest simply braking harder into the corner to get the rotation, however, then you may scrub too much speed which conflicts with goal #1 above.

My guess would be that you need a little front bias in your car with a less aggressive pad, especially with your suspension and sticky tires. RS14 f/r may be too much. Too much bite and more difficult to modulate. Touch the pedal and you've already scrubbed too much speed.

Going RS29 or RS19 all the way around should maintain some of your front bias and allow you to rotate with easier modulation. If you make this switch and you are now over rotating, then throw the RS14 back in the rear.

If you run RS29 or RS19 all the way around and you are still under rotating the car then you should probably adjust your driving, as in carry more speed or dial in more steering, rather than throw in RS14 up front. Your high speed straight line braking stability will suffer with too much front bias.

If RS29 or RS19 is not enough brake for you then you can go back to RS14 f/r and adjust your driving or make some suspension tweaks.

My guess is that RS19/14 f/r is not the solution you're looking for... although I'm not quite clear on the issue you're having.

Larry Herman

Funny, in reading this thread, I find that brand X pad is cheaper than Pagids, but doesn't work quite as well, brand Y works good but wears out quickly and dusts really badly, and brand Z eats rotors. I guess that's why many racers do run Pagids. If you factor in performance AND life cycle costs I think that Pagids come out on top, especially the RS-19s.

Rickard 993 Turbo

So Bob i that have a GT2 with Alcon steels 362mm i front and 350mm, and have bought Rs29 F/R do you yhink i should stay with that or should i change to Rs14 in the rear

Chris L.

Wrong...as I cannot seem to convey what I am "feeling".

I have been thinking of trailbraking more in regards to allow me to carry higher entry speeds more than helping rotate the car, though obviously it does this.

My problem has been two fold:

1. I feel as if the hard initial bite with the RS-14s is such an on/off thing that I am scrubbing too much speed off as well as having to be careful to NOT over rotate the car initially.

2. Straight line braking at the end of the straights can get to be a "handful." I know it is not suppose to be a walk in the park but...

That is what I am referring to.

I just thought that more modulation in the front pad would help with #1 and less front bias would help with #2.

Is that correct?

Chris L.

Larry: that is what I am looking for. I am the kind of guy that has to look at all the information and search for weeks just to know what the best ink pen there is I can purchase!

I may be doing this with my pads. Synergy works on the car and suggests something to me. I don't hear of any other Porsche guy going this route of PFC with their pads and before making a decision just wanted the most info I could get.

Sounds like Pagids are the best way to go.

Thanks.

Larry Herman

Chris, everything is a trade-off. I tried the RS-19 front/RS-14 rear on my GT3 and did not like the combination. Yes, the car does stop a tiny bit quicker because you are using a little more of the rear brakes, but I felt that it added some straight-line instability under braking.

I also like to trailbrake to varying degrees, and felt that the car rotated too easily with "grippier" rear brakes. I like to make the car rotate, not have it automatically occur. I feel that it gives me more control, and allows for higher turn entry speeds. I might have tried the 19F/29R setup, but they were not available until the tail end of the 2005 season when I sold the car.

BTW I am in total agreement that pads with "high initial bite" are the main cause of overbraking. I want progressive grip, and smooth release. There are only a few places on a typical track where I will need maximum braking, and even in those places, brakes that are too grabby will pitch the car forward and upset the balance.

RJFabCab

I understand more clearly now.

Too much bite up front pitching the car as you turn. Your logic about going RS19/14 f/r seems appropriate. How about just barely touching the pedal as you enter? Still scrubbing too much speed and pitching the car?

I am interested in Larry's comment: "I felt like the car rotated too easily with 'grippier' rear brakes". Can you comment more on this dynamic, Larry?

Larry Herman

I find that unless the turn is a very high speed sweeper, I am trailing the brakes into the turn to some degree. Specifically, I ramp up the pedal pressure on initial braking, and am at maximum pressure early in the braking zone. As my speed drops and the corner approaches, I start easing off of the brakes, timed with turning into the corner. At this point in the turn, I start to generate maximum cornering force on the rear tires. If I have more rear brakes, then I have less grip for cornering, and the rear will start to drift more easily.

If I have a little less rear brakes, then the rear will stay planted, and I could possibly have to deal with some understeer. The remedy for that is to turn-in at a higher speed, staying on the brakes a little more, and leaning harder on the rear tires, making them drift. That is what I meant by causing rotation. This can allow me to brake a little later, even though my overall stopping power is a little less. Of course, if I have too little rear brakes, the thing just won't stop!

DanH

I have that setup on my RS along with a Manthey geo and Toyo R888s. Very happy with it. Got as much rotation into the corner as you could want - in fact some think it is a bit tail happy for their tastes but I'm content.

mfennell

Maybe I'm not reading closely enough but this thread has some conflicting opinions here. Is this one of those weird/charming ***-engine things?

In any other car, I want more rear brake if I want more rotation as I turn in under braking. As someone else pointed out, more brake=less traction available for turning. In my Factory Five Cobra, I've gutted the stock Mustang bias valve to get some more rear brake and (hopefully) some rotation. My old Spec RX7 had exactly the opposite problem as these GT3s; too much rear brake bias. In the absence of a bias valve, we ran less aggresive pads out back. Hawk Blues up front and the Hawk street/track pad in the back. Even Blacks made the car a handful under braking.

Timely group of threads touching on brake biasing. The first time I got on the (stock, steel) binders hard I thought "that can't be right". The fronts go into ABS pretty quickly. I had been guessing that the brakes were simply biased in a don't-let-them-hurt-themselves configuration from the regular 996s.

LVDell

Not sure I follow. Think about it. You produce more squat in the rear (more brake) you will increase the level of grip on those tires but if you have more front bite and less in the rear your rear will slide out easier under trailbraking. Maybe somebody that has done both combo's can chime in with better explanation of their experience.

multi21

I found the ABS over active with the OEM pads. After putting RS19's all around and a day at Laguna Seca, I didn't have any of the ABS issues. BTW, tires were the same as when I used OEM pads.

Larry Herman

Dell, when you get onto the brakes, weight shift will cause the car to pitch forward. The amount of weight shift will be determined by the rate of deceleration. That shift unloads the rear tires; there is no squat effect under breaking. So the more braking the rear tires do, the less is available for lateral loading. PM me if you still don't agree with this.

Chris L.

Likey...likey.

I follow you my friend and see where you are going.