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Distance between brake and pedals too much?


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Bill,

Around town,and doing canyon runs (spirited driving), I always heel-toe, (it's good practice) and in light brake pressure situations, I agree that the throttle is too low, or the brake too high for proficient heel-toe work. However, on the track, where the brake is applied with vigor, (by vigor I mean that the seat belt leaves bruises on your shoulder) I find that it is just fine!

:drive:

-Sean

Edited by quicksilver77
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Bill,

Around town,and doing canyon runs (spirited driving), I always heel-toe, (it's good practice) and in light brake pressure situations, I agree that the throttle is too low, or the brake too high for proficient heel-toe work. However, on the track, where the brake is applied with vigor, (by vigor I mean that the seat belt leaves bruises on your shoulder) I find that it is just fine!

:drive:

-Sean

Sean, thanks for the reply.

This brings up another question. In my car, it seems the weakest

point is the braking traction of the front tires. I have 17" wheels,

and the Michelin Pilot Sport (not the "N" marked OEM).

Cornering they seem fine, but braking performance leaves a lot to be desired.

Is this normal?

Bill

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Bill,

Around town,and doing canyon runs (spirited driving), I always heel-toe, (it's good practice) and in light brake pressure situations, I agree that the throttle is too low, or the brake too high for proficient heel-toe work. However, on the track, where the brake is applied with vigor, (by vigor I mean that the seat belt leaves bruises on your shoulder) I find that it is just fine!

:drive:

-Sean

Sean, thanks for the reply.

This brings up another question. In my car, it seems the weakest

point is the braking traction of the front tires. I have 17" wheels,

and the Michelin Pilot Sport (not the "N" marked OEM).

Cornering they seem fine, but braking performance leaves a lot to be desired.

Is this normal?

Bill

Bill,

I am not sure I am understanding you completely... Under braking you are losing traction with the front wheels? Help me understand you better.

Under braking, (I am assuming that you do the lions share of which in a straight line prior to turning in), The weight of the car is transfered to the front, which effectivly IMPROVES traction at the front of the car. So under what circumstances do you feel that front traction is lacking?

I also ran Pilot Sport OEM tyres for a year or so, although it was on an 18 inch wheel, and I have nothing but good things to say about the tyre. Although the PS2's do offer a measurable improvement, especially when the road gets wet!

Wish I could be more help.

-Sean

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Bill,

I am not sure I am understanding you completely... Under braking you are losing traction with the front wheels? Help me understand you better.

Under braking, (I am assuming that you do the lions share of which in a straight line prior to turning in), The weight of the car is transfered to the front, which effectivly IMPROVES traction at the front of the car. So under what circumstances do you feel that front traction is lacking?

I also ran Pilot Sport OEM tyres for a year or so, although it was on an 18 inch wheel, and I have nothing but good things to say about the tyre. Although the PS2's do offer a measurable improvement, especially when the road gets wet!

Wish I could be more help.

-Sean

Sean,

Yes, I'm not in the habit of braking hard in a turn. ;-)

I'm saying, braking in a straight line, the front wheels start to lose traction,

and the ABS kicks in a lot sooner than I would like. I'm not getting any bruises

from my seat belts.

The car seems to track properly, handles great, and doesn't get at all

twitchy under heavy braking, so I'm assuming the front end alignment

isn't causing this. I'm running about 33 psi in the fronts at present.

I have noticed the tires seem to work much better heated up.

A friend with a 2000 C4 has 18" wheels and brand new Pirelli tires

(not sure of the model) that he is going to let me put on my car and

experiment with.

Bill

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Bill,

I am not sure I am understanding you completely... Under braking you are losing traction with the front wheels? Help me understand you better.

Under braking, (I am assuming that you do the lions share of which in a straight line prior to turning in), The weight of the car is transfered to the front, which effectivly IMPROVES traction at the front of the car. So under what circumstances do you feel that front traction is lacking?

I also ran Pilot Sport OEM tyres for a year or so, although it was on an 18 inch wheel, and I have nothing but good things to say about the tyre. Although the PS2's do offer a measurable improvement, especially when the road gets wet!

Wish I could be more help.

-Sean

Sean,

Yes, I'm not in the habit of braking hard in a turn. ;-)

I'm saying, braking in a straight line, the front wheels start to lose traction,

and the ABS kicks in a lot sooner than I would like. I'm not getting any bruises

from my seat belts.

The car seems to track properly, handles great, and doesn't get at all

twitchy under heavy braking, so I'm assuming the front end alignment

isn't causing this. I'm running about 33 psi in the fronts at present.

I have noticed the tires seem to work much better heated up.

A friend with a 2000 C4 has 18" wheels and brand new Pirelli tires

(not sure of the model) that he is going to let me put on my car and

experiment with.

Bill

Bill,

A common problem with the 996, and often noted, is the "floating" feeling from the front end of the car. Although it was most apparent to me in transition from corner to corner, perhaps it is contributing to your traction issues? My fix was the addition of RoW M030 (european suspension) as opposed to the increased ride height US spec suspension, which seems to cause the floating feeling.

In regards to the brakes, I have done nothing to the calipers or rotors, but I have changed to Super Blue brake fluid and added stainless steel brake lines at the front and rear. I can not imagine that these changes would cause my car to stop any better than yours, under normal situations. So essentially we have the same brakes on our cars, and I do not experience the same poor traction issues...

So let's hope that tyres are the problem, that would make life easy! :lol:

Good luck!

-Sean

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Bill,

A couple of thoughts, from 0-more expensive checks:

1. More air on the fronts tires (I run 36 in city, 41-42 on track) may help. It could be why they fell "better" when warm since they are tighter.

2. Have you changed front pads lately? Perhaps glazing on the rotors is causing the ABS early kick in. Some fine or ultrafine grit sand paper, sanding radially on the rotors may help remove it.

3. Finally, try new or different pads. Or see if you know someone with old or track pads you can do a swap test.

What you describe doesn't seem normal to me. Only under very wet or icy conditions.

Izzy

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Bill,

A couple of thoughts, from 0-more expensive checks:

1. More air on the fronts tires (I run 36 in city, 41-42 on track) may help. It could be why they fell "better" when warm since they are tighter.

2. Have you changed front pads lately? Perhaps glazing on the rotors is causing the ABS early kick in. Some fine or ultrafine grit sand paper, sanding radially on the rotors may help remove it.

3. Finally, try new or different pads. Or see if you know someone with old or track pads you can do a swap test.

What you describe doesn't seem normal to me. Only under very wet or icy conditions.

Izzy

Thanks for the ideas.

1) I'll adjust the tire pressures and see what effect it has.

2) Well, I don't know. The car is just as I got it from the dealer, CPO. Do they normally change brake pads for when selling CPO cars? I'll take a look at the rotors.

And I will try my friend's 18" wheels.

Another aspect of this is, without measuring instruments it's hard (for me) to judge

braking performance. It just doesn't seem fabulous and I'm not showing any bruises

from the seat belts.

Bill

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Bill,

As I get ready to take the car on a canyon run or out onto the track I move my seat back 3-4 inches and then put on my seatbelt. Then I give the seatbelt a quick jerk so it locks at a certain length and I advance my seat position back to the proper position; all the while keeping a load on the seatbelt, to keep it from moving. As I move forward my body then applies the load to the seatbelt, and effectively locks me into place, keeping me from sliding around the cockpit. A four or five point harnesses would be better, but I would need new seats, so that will have to wait for a while, in the meantime this trick with the old three point restraint is getting me by. After a day at the track, my shoulder is tender, but there is no visible bruising. Sorry to make you think that the car was going to beat you up that bad!

But back to the subject matter, P-cars are renowned for their braking abilities, so if you still have issues with poor braking, it is not normal. If it is a CPO the dealer should be receptive to your issues. As far as Porsche installing new pads before sale... I would find it unlikely. I think they just inspect items, and if they are within their arbitrary spec then they are left alone.

Keep us posted!

-Sean

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But back to the subject matter, P-cars are renowned for their braking abilities, so if you still have issues with poor braking, it is not normal. If it is a CPO the dealer should be receptive to your issues. As far as Porsche installing new pads before sale... I would find it unlikely. I think they just inspect items, and if they are within their arbitrary spec then they are left alone.

Keep us posted!

-Sean

Braking is excellent, don't get me wrong. I just expect more.

(while I'm not bruised, passengers are s**ting themselves)

As for the dealer being receptive... I've never hard a worse opinion

of an experience with a car dealer.

Bill

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I ususally make my passengers sit on plastic garbage bags and towels! It keeps the mess off the seats! :clapping:

I am very sorry to hear about your dealership woes! It really sucks that after you pony up for a P-car that they do not "take care of you!"

How did the wheel/tyre swap pan out? Or have you done it yet

-Sean

Edited by quicksilver77
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I ususally make my passengers sit on plastic garbage bags and towels! It keeps the mess off the seats! :clapping:

I am very sorry to hear about your dealership woes! It really sucks that after you pony up for a P-car that they do not "take care of you!"

How did the wheel/tyre swap pan out? Or have you done it yet

-Sean

Haven't tried his wheels yet. Haven't even driven my car since!

He's always busy, I've been shipping a ton of eBay junk, and the weather hasn't been dry enough at the right times.

The dealer stinks, but I love the car. It goes like stink. To me, it feels more nimble, lighter, more authentic 911 feel, and quicker than my friend's 2000 C4 Cab. The full story is I had a burst appendix which induced a midlife crisis. He loaned me his C4 for a week, and shortly thereafter I bought mine. I can't believe I had considered buying a new VW GTI to "roar around" in. My dear sweet wife thankfully talked me out of that.

Bill

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I put 36 psi in the fronts this morning (30F outside). Roared around the backroads

on the way to work. Checked the pressure when I stopped, and it was 39 front,

40 rear.

Tires didn't feel too warm, but the rotor hubs were too hot to touch.

Results. Front end of the car feels very different with 36 psi vs. 33.

When cold, the brakes lock up easily. I am not talented enough to

identify if it is the brakes grabbing or the tires simply don't have traction,

but given the cornering power seems fine, I assume it is the brakes.

As the whole system warms up from spirited use, the brakes work much

better, more powefully, and do not lock as quickly. They work nicely.

So I'm wondering if it is the coefficient of friction in the cold pads being

much lower, resulting in me pushing harder on the pedal, and then they

grab and lock up. Vs. when hot they work better, with less pedal effort,

smoother, and less prone to grab and lock. Is that possible?

Bill

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Bill,

A couple of observations. Take them for what they're worth.

Great braking means a lot of systems (tires, brakes, pads, suspension, your foot) have to work well together. Your car isn't quite optimal. Assuming you have 205/255x17 tires, they are considerably smaller than you would like them to be. The stock suspension is pretty compliant meaning your nose is dipping and your rear is lifting much more than you would like under heavy braking. Your brakes are heavily biased to the front and, it sounds like you are really jumping on the brakes.

Here are a few ideas (some of which others have already suggested).

1) 18 inch wheels with 225, 235 or 245 tires will help. Both because of the wider footprint and the stiffer sidewall.

2) a stiffer suspension (both compression and rebound) will help.

3) using a higher friction pad in back than in front will really help with the forward bias. I use Pagid Orange on front and Black on back.

4) when braking, think in terms of slowing as fast as you can within the limits of the car. Just jumping on the brakes distorts the tires and upsets the suspension. Think about first setting the suspension and shifting the weight and then adding heavy braking. It takes a little practice but will work much better.

Hope this helps,

Jim

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I've got my friend's 18" Sport Classic wheels with new Pirelli P-Zero tires on the car for a test. Man, they do make the car feel better all around. I will weigh them when I swap back, but they feel a lot heavier than the 17 inchers.

Bill

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  • 7 months later...
Bill,

A couple of observations. Take them for what they're worth.

Great braking means a lot of systems (tires, brakes, pads, suspension, your foot) have to work well together. Your car isn't quite optimal. Assuming you have 205/255x17 tires, they are considerably smaller than you would like them to be. The stock suspension is pretty compliant meaning your nose is dipping and your rear is lifting much more than you would like under heavy braking. Your brakes are heavily biased to the front and, it sounds like you are really jumping on the brakes.

Here are a few ideas (some of which others have already suggested).

1) 18 inch wheels with 225, 235 or 245 tires will help. Both because of the wider footprint and the stiffer sidewall.

2) a stiffer suspension (both compression and rebound) will help.

3) using a higher friction pad in back than in front will really help with the forward bias. I use Pagid Orange on front and Black on back.

4) when braking, think in terms of slowing as fast as you can within the limits of the car. Just jumping on the brakes distorts the tires and upsets the suspension. Think about first setting the suspension and shifting the weight and then adding heavy braking. It takes a little practice but will work much better.

Hope this helps,

Jim

OK, (1) is done. I have switched to 18 inch wheels. 225/40 on 8 up front, and 285/30 on 10 in the rear.

Car feels a lot better.

Why does the factory recommend such a different pressure setup with the 18s vs. 17s?

36 psi up front, 42 in the rear. Is that a good starting point?

Bill

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