Brakes upgrade question

[Andrew2KRT10]

I don't want to get into a $3000 upgrade. All I am interested in doing is changing the stock rotor to the Stop Tech rotor. And, I am only thinking of doing the front. At W. Glen, I ran upgraded pads with stock rotors and after the end of the day my pads were okay, but the rotors were all chewed-up. So, I figure that the stock rotor is the weakest link and I should change them. Here is the question: Can I use the upgraded rotors with the upgraded pads on the street? Any disadvantages of using them on the street? I figure I may as well have them. Who knows when I may kick up the speed a bit and need those brakes?
If anyone is going to now offer to sell me the upgraded components after reading this post, may as well include the price & availability.

Thanks,
Andrew

 

[Anthony - 98 GTS]

Andrew,

I was in the same position as you - wanting to upgrade braking without spending thousands of dollars.

I just purchased a set of Baer Eradispeed rotors for my GTS. The rotors are cross drilled, slotted, have billet aluminum hats, extra heavy duty cheeks, 25% more "firepath" and are zinc washed.

They should increase performance and LOOK absolutely amazing. I realize these cannot compare with the full brake systems from StopTech and others but I was able to get all 4 rotors and hats for $999.00.

I don't have my car on the road yet so I can't give you feedback on the performance.

Good luck,

Anthony

 

[Tom F&L GoR]

Hi Andrew. What did you use for pads? In my few experiences, the pads got used up first, rotors were still useable. How many track miles on the rotors?

 

[LTHL VPR]

We have 3 options for you:

1) We carry (and have in stock) the Eradispeed 2-piece stock replacement rotors (they are slotted AND cross drilled; looks cool!)Recommended for street and light track events

2) We carry (and have in stock) the StopTech 1-piece stock replacement rotors. Recommended for street and light track use.

3) We can get the StopTech 2-piece stock replacement rotor.
**Recommended for track use and street use.

You might want to consider upgraded brake lines and fluid. We have everything in stock, and can price out a package for you. Upgrading to a 2-piece rotor will improve cooling and longevity. Even the 1-piece offers the advantage of significant weight savings with rotating mass.

Call me at 408.562.1000 to discuss.
Thanks!
-Wayne

 

[luc]

Repeat after me: "I WILL NOT USE CAST IRON CROSS DRILLED ROTORS ON A RACE TRACK"

Cross drilled rotors WILL not last on a track.
Heat related cracks will appear after a few sessions,those cracks will start small and grow from holes to holes.

No racers use them for this reason,cross drilled rotors are for show NOT go.

Now,you are going to say that Ferrari or Porsches use them,right?
BIG difference,rotors used on those cars are either made out of STEEL or are CAST with the holes.
All the after market cross drilled rotors that I know,Wilwood,etc, are drilled AFTER being cast.
Best rotors for the track are slotted rotors with a GOOD cooling system.
Luc.00GTS

 

[Jim Hodel]

My experience with brake upgrades is that cross drilled and/or slotted rotors don't do anything for reducing stopping distance or reducing fade. I have tested several different pads on my Alcon equipped Z28 along with plain and slotted rotors. The pads made a big difference, but I could determine no difference in stopping distance or fade resistance between the slotted and plain rotors. I even tried some zinc washed rotors, and after a couple of track days they didn't look any different from the regular rotors.

That is not to say that the Baer and/or Stoptech rotors don't have other improvements.

If looks are important, by all means go for the drilled, slotted, and washed rotors. At $1000 for rotors alone, you are almost halfway to the price of the Stoptech full caliper and rotor upgrade.

I have the Stoptech system on my 99 GTS and am still experimenting with pads. The Axiss Ultimates melted on my first track day and I now have Pagid oranges which I have not yet run on the track. BTW, the kit came with slotted rotors and when I wear these out, I'm going to save myself some money and buy the plain rotors.

Jim

 

[Gavin]

Hi Andrew,if you are not putting your car on the track - no worries with your plan.
If you are - then there is no cheap date here.
Keep in mind that the rear brakes of the viper are the weakest part of the stock system. Those dinky little pads and calipers are just "along for the ride".
So... to modify just the front end of the car is only a partial solution and you will end up, in my humble opinion, making changes because you will not be satisfied with the results.

I believe it is most important to have a balanced braking system, balance between front and rear. Throwing large calipers or larger rotors or race pads on the front will lead you to several problems many of which are discussed in previous posts.

We have a guy in our club who has a stock 96GTS and he is always one of the quickest at track and autocross events.
He runs a stock system except for the following: high temp brake fluid - most of us use Motol 600 - upgraded pads - porsche cooling ducts ($19 a pair)
These modifications will keep the brakes intact (no fade - or at least very little) in a 20-30 minute session at Laguna Seca which is notorious on brakes. Without these modifications 10-12 minutes on the track and the pedal will go to the floor.

I suggest you make these changes first. Do a track event - if you feel you need to do more then you really should look at a complete front and rear set up. I can recommend Sean Roe Racing as a good place to start - his package is not about "looks" - its about getting the car stopped.logon at www.roeracing.com

Happy to chat with you on this email me and I will give you my telephone number.Gavin

 

[Bob Woodhouse]

Some really great information provided by a good many of you here. Some not so great but welcome just the same. After 5 years of doing my best to go over the design limit of brakes on Vipers I can agree with the following:
Drilled rotors mean little to nothing followed closely by slotted rotors. This fella "luc" on here knows of what he speaks. One piece rotors are street rotors with an occasional short track session. Heat expands things and when held solid by the center (as in one-piece) they will warp and wobble, eventually crack and break up. Do not wait for large cracks. If you have seen a rotor bust up you will understand.

Good quality two piece rotors are easy to find at 200 to $300 each once you have the hat bought. That makes them less expensive as replacements due to less frequency. Stop-Tec 2-piece is good. Brake-Man is good. Rotors that last are heavy. Mass allows the rotor to absorb the heat, thus heavy rotors will not lose your pedal as quickly but they do increase rotational and unsprung mass.
As heat increases so does pad wear. Wear rate is the square root of heat ie: wear increases dramatically with temp. Thus the reason for a set of pads at one track event. Finding LIGHT-WEIGHT two piece rotors takes money, say $900 each rotor as it takes high technology to dump the heat without mass.
I would question a brake upgrade to one end only. Pads change their friction characteristics as heat comes and goes from your brake system. Engineers figure out what that should be front and rear and try to get the brake temps somewhat parallel. If you do not design the system properly you may never understand why you spun out or hit that tree. Many retailers have allowed you to be the R and D dept. Several of my friends have invested in bad brakes due to someones marketing skills, not brake knowledge. Brake systems need to be hydraulically balanced as well, very unwise to change piston sizes etc. without an engineering degree. Suppliers leave that up to you. Brake-man does not, Stop-Tec does not.
Calipers, choose wisely, big difference here as well, in quality, ability to withstand heat, amount of flex when hot and with 1200 lbs line pressure, Do they need to handle a 14" rotor in a 17" wheel? Are they easy to rebuild?

Brake pedals go to the floor due to temperature in the brake fluid. Brakes need cooling air, Vipers run wide front wheels making it difficult to get circulation into the front brakes. The "P" word deflectors are good for street and occasional track, 3" ducting is good, 4" is difficult to install but the best.
The most dramatic improvement for fluid temperature management is a brake recirculation system. E mail if you need more info.

 

[TAPROOT]

I have a $3K+ BAER Racing Brake system upgrade on my SS camaro and I LOVE THEM!It is a night and day difference.They also make a STOCK Baer replacement rotor(smaller) for my camaro which is much better than the stock.Maybe they make the stock size rotor replacement for our Vipers too????I have to give them a call.I know they make the Alcon replacement system thou.... 3K+$

 

[Tom and Vipers]

I'm going to do a brake upgrade sometime in the future and one factor for me is rotor cost because rotors are basically consumables.

For the stock system with track pads, fluid, and air deflectors, what gives out? The fluid?

Therefore, would brake fluid recirculation system, be next step here?

 

[Andrew2KRT10]

Wow. Great info and e-mails I have already from some of you. Seems that I should have provided some better info in my first post. I have "P" deflectors, stock rotors all around, Motul 600 fluid, and Archer replaced the pads. What has me puzzled is this: I went to VOI 6 with the stock pads and rotors that the car came with. The car was new. At St. Louis, Archer recomended that I change the fluid and the pads. I had them do it. I ran the car a total of 6000 miles on these same pads. VOI 6...St. Louis, Pocono twice, Englishtown autocross & drag twice, another autocross once, and regular street driving.......all on the same pads that Archer changed back at VOI 6. And I am not light on the brakes. I have always pushed the car as much as my experience would allow. It wasn't till Watkins Glen when all hell broke loose. I started at Watkins with the same good, stock rotors and had Archer install new pads (Blue) and they changed the fluid to new Motul 600. After 4, 30 minute sessions, my pads were still good, but my front rotors had grooves in them. You could run your finger across the rotor and feel the grooves. The back was fine. SO, WHAT HAPPENED? Is Watkins Glen that ******* brakes? Maybe I should just get my stock rotors cut, run them as long as posible, and when the time comes just replace them with new stock rotors and pads. Hell, this combonation lasted me 7000 miles. I need a good street/track combonation, and maybe I already have it.
Any input appreciated.

Andrew

 

[Gavin]

Hi Jim, you and I are on the same page - I installed front and rear upgrades for the same reasons you state, I am a firm believer "if you're going to go quick you need to be able to stop quicker and be able to do that as often as needed".

My warning regarding upgrading fronts was not vague, but rather quite clear I thought. My reasons:
Prior to making my purchase of the particular package I thought was best for my driving circumstances I talked to everyone I could, I read every post on this board regarding braking systems upgrades for about nine months, I went to multiple track events and talked to viper owners, viper techs, the companies you mention and more.

Initially, I observed viper owners installing systems , running them. My observation very early in, was the folks with the biggest problems fell into one of two groups. Group A installed front only setups - this method makes no improvement to the rear braking effect, and this is the part of the system that needs the most urgent help.This group were not entirely happy campers
Group B installed proven front components but what I consider unproven or experimental or mis matched rear components - my observations this group were in the most trouble.

At this time I had not found anyone offering a complete front and rear package. Lots of front packages.

Then I attended a Viper Days track event where a number of guys were set up with the same system, a complete package of Front calipers, rear calipers, braider lines, brake cylinder, pads etc.
Frankly speaking, these fellas were Hauling A.... around the track - they were quick. I hung around, listened in and learned a lot.
These guys were very positive about the results they were getting. Subsequent to this track event a couple of them posted their comments on this board.

I forgot to mention....
Prior to the track event there was a very extensive, highly technical discussion on braking systems between two folks that sell aftermarket systems. Their discussion picked up again after this track event.

The information from all these sources led me to purchase the same system used at this track event. I have completed two open track events at Laguna Seca and firmly believe I made a very sound choice.... for me and what I expect from my car, based on the way I drive. By no means do I think the solution I chose is for everyone. Each of us has to make our own choices.

What I do know was that ALL the information I read and ALL the conversations I had, were extremely helpful.The posts on this board were particularly helpful.

So...ANDREW
I still think it is a mistake to upgrade the fronts only. There is just too much load on the front of the car and the rears are not participating in getting the car stopped.
It is even a bigger mistake to throw untested components at the rear of the car - even more potential for things to go wrong.

Read all the posts, be patient, decide what others have done successfully that might work for you. Avoid like the plague anyone that is "well we are working on this", or "We are testing that".
If its a system going on a car that is going on the track then it has to be a system that has been correctly engineered by someone that knows their braking systems theory and has tested their system at the track, on a viper, extensively - otherwise its a crap shoot - you might get lucky - you might not.
Gavin

 

[Jim Hodel]

Hi Gavin, if your point is that good driving is more important then big brakes, I agree completely. However, there are a lot of drivers like me who prefer the peace of mind associated with brakes that fade less, stop better, and are easier to modulate then the wimpy stock brakes. I am sure that a more skilled and daring driver running stock brakes will beat me around the race track, but I'm happy with upgraded brakes that make track driving more comfortable.

I don't quite agree with your vague warnings about changing only the front system. I think there are a number of front only upgrades that can improve the braking performance of a Viper and not upset the balance. I do agree with your recommendation to run some track days with the basic pad, fluid, and deflector upgrades. I did just that on my Viper and the braking ability was still the weak link in the car. I had to brake considerably earlier then in my Alcon equipped Z28 on the same tracks.

The Stoptech system has fine braking balance. It is easier to modulate and stops better from high speed. I think other front only systems like Brembo, Baer/Alcon, and Mov'it Big Reds will also work well for occasional track day enthusiasts like myself.

Jim

 

[Andrew2KRT10]

Gavin & everyone:
Again, thanks and I hope to keep all this info coming. If I were going to do many track events and use the car a limited amount on the street, I know already from you guys which way I would go. But if I understand correctly, when driving on the street, the all-out track upgrades might not be such a good idea because they would not generate the heat necessary to stop as needed.
[Alan Modzelewski: "I do run the stoptech rotor and R-4 on the street in between events, some squealing but less than the delivered stock setup. If used on the street and really needed in a desperate maneuver they might not deliver the stopping distance as a stock pad since they have no heat really built up in them to become more effective."] I don't want this to happen, so I need to figure out the best combonation. I think I should just stay with stock rotors, upgraded pads, and keep an eye on the rotors. Like I said two entries ago, I got 9000 miles on my stock rotors and that's not bad.

Andrew

 

[luc]

Since I don't race my Viper,I can't tell you exactly what you need on it,but I do a lot of racing with a 69 Mustang with 650 HP and a 65 with 550HP,and brake is really what separate good cars from great cars.

Most of the Vipers that run with us complain of brake fade.

Brake fade is due to heat,so cooling is the # 1 priority.
You need to have a good air ducting system that direct the air to the center of the rotors.
Directional vanes in the rotors are designed to pull the air from the center to the outside of the rotors.

Keeping brake fluid cool.
Beside using a good quality fluid as Motul 600 with a high wet boiling point,the best way is to use a Stuart re-circulating valve.
In such a system,you plug an extra brake line on each caliper from the bleeder port and every time you brake some new "cooler" fluid is pushed inside the calipers.

1 piece rotors compared to 2 pieces.

Rotors expend/grow due to heat.
On a 1 piece rotor,since the rotor is solidly mounted on it center,and due to the fact that usualy the center is of a different thickness that the pad area,thermal expension not only is not linear but their is no "room" to expend without warping the rotor.
The rotor also transfer a lot of heat to the hub/bearings area.

On a 2 pieces rotors,that usualy is a combination of a cast iron rotor and an aluminum hat,which consequently have 2 very different expension rate,the rotor can expend/grow independently from the hat.
Also in this case a lot less heat is transfered to the hat and of course to the hub/bearing area.

Plain rotors,cross drilled and slotted rotors.
By reading the precedents posts you know why a cross drilled rotors is a bad idea.
A slotted rotor doesn't offer more braking,it could even be argued that it offer less braking since the contact area between the pads and rotors is less due to the groove,BUT the 2 reasons to use slotted rotors are:

"Degasing"
I am not even sure of the spelling,but the friction and heat created when the pads are "clamping" the rotor, can create a boundary layer of gas between the pad and rotor that can decrease the coefficient of friction and consequently the braking.
The slots in the rotors give this gas a place/pathway to escape.

Scrubing/cleaning.
This one is pretty simple,if you get a piece of junk/debris caught between the pad and rotor, the result can be a damaged/grooved rotor.
Once again the slots offer a place/pathway for the junk to escape.

Proportioning valve.

As it imply,it is a valve thaty reduce/increase the line pressure (usually from 45% to 100%)to the rear.
Very useful to balance front to rear braking.

Master cylinder bore.

Control the brake pedal feel/travel.
A smaller bore will move less fluid and soften/reduce pedal effort and increase pedal travel.
A bigger bore will move more fluid and harden/increase the pedal effort and decrease pedal travel.

Luc.00GTS

 

[Gavin]

Andrew - I don't necessarily agree with Alan - I know my system does not demonstrate the symptoms he speaks of.

I can tell you this - I have a almost 50 yds downhill concrete driveway - the trip down is always down with caution and the brakes are less effective than the stock setup for sure. I then drive 1 mile to the highway without having to brake until I get there. The pads come up to a temperature that provide braking superior to the stock set up but not even close to what I get when the system is HOT.
I drive on the street 6-7 days a week and my setup is great. I have had to change my braking behaviour - no more light braking, otherwise the pads get squeaky. Generally I brake quite firmly, and coast up to a stop - no squeaky pads doing it this way.

Luc knows of what he speaks. I think he is describing the ultimate track set up. We all should be working toward a brake setup such as he describes.

I do not have the 2 part rotors - yet. When I go to slicks this feature is a must. With Street tires and 13" rotors I'm comfortable. I do a number of laps in the parking lot. after a track session to cool off all the components and minimize warping. I have had to have my current rotor machined - they were warped. Stock rotors are cheap fortunately.

The 96GTS rims do not hold up with repeated track use - they develop cracks and eventually can fail - if you are using stock rims inspect them every session for cracks - even if they are later than 96. If you go to sticky tires (slicks) aftermarket rims are a must.

This is tons of information to digest - bottom line - you can improve your braking system in a progressive, step by step method without spending money twice, based on the activities you are putting the car in, how hard you are driving the car and whether you are running street or track tires.

It might look something like this:

1. Motol 600 - "P" cooling ducts - R4 pads (turn the rotors) - I understand you have done this. Street tires.

2. After market front and rear caliper upgrades, braided steel lines, Proportioning valve, new master cylinder. Street tires.
(note - your front rotors will warp - carry a spare set to the track + pads)- have this equipment professionally installed.

3. 14" 2 part front rotors, 18" rims front, 17" rims rear (aftermarket) Sticky tires, cooling ducts. At this point you also need to talk to the guys that know about changing seals and things in the calipers so these parts don't fail due to heat. I'm not at that point so know enough to know something has to be done but I haven't taking to time to get into it to understand the specifics.
Side note ( I have obtained a spare front facia which I'm getting modified to provide extra bake cooling and engine cooling - this is about a one hour swap before a track event - crazy - guess so, but its something to do)

Luck
Gavin

 

[Jim Hodel]

I believe that a 'properly balanced' four wheel brake system will provide better stopping power and fade resistance then a front only upgrade. However, I also believe that a 'properly balanced' front only system will provide better stopping power and fade resistance then the stock system (I put properly balanced in quotes to indicate that there is often as much 'lore' as there is 'fact' in marketing commentary).

I put more faith in the real life experience of my fellow enthusiasts who have tried systems and found success (Gavin, Alan, Luc, Taproot, etc). My front only Alcon upgrade on the Z28 is a total success. I just got done driving the Z28 at another track day today, and the braking performance was excellent (another rainy day here in the Northwest).

In my opinion, the front only system on the Viper is also an improvement, although not as dramatic as on the Z28. I do not have nearly as many track days on the Viper as I do on the Z28, and I am still experimenting with pads, so I would not say I know exactly how well the system performs yet.

Maybe some 14 inch rotors and appropriate rear brakes are in my future, but I need several more days of driving before I'll decide to make any other changes. I am trying to be methodical and change one thing at a time, but that does take awhile. Maybe that's half the fun...

BTW, I made a spreadsheet of the piston sizes of various calipers, after I read the threads discussing how changing piston sizes can affect brake balance and pedal feel, and maybe require a change in mater cylinder size. It's kind of interesting (at least too me). If anyone wants to see it, let me know and I'll send you a copy.

Jim

 

[Sean Roe]

Hi Guys,
Good thread.
Since a lot of people into brakes will be reading this, I'd like to take a moment to say something.
For those that would like to know what was determined to be the cause of the brakes dragging on the Viper that had the same brakes I used in World Challenge, drop me an e-mail and I'll forward you the information. I'd prefer that you e-mail me only if you know what I'm talking about and the history. I told people we'd let them know what we found, so that's what I'm doing.

 

[Gavin]

Jim, have to agree with you. I do believe upgrading just the fronts is going to result in flat spotted front tires - a couple of sets of those would pay for upgrading the rears.

I think the rear brakes on your Z28 have contribute more to the overall braking effect than do the rears on the Viper. Whadayathink?
Gavin

 

[Andrew2KRT10]

New update:
I was changing the oil and other things yesterday when I realized that the stock rotors are not only grooved, but cracked. Maybe some dirt did get in there at W. Glen. Small map-like cracks. I plan to run them for a short while and then replace them.
How about this? After reading all the info that came up from this thread, I'll replace with all stock equipment. Then I will purchase a second set of Stop-Tech (or similar) rotors and upgraded pads to use for the track. I'll just prep the car for the track when I go to the track. I run Hoosiers on the track & change them, may as well change rotors and pads at the track also. At the end of the event, switch back. I don't drive my car daily, and the few times that I take it out, I may be a little aggressive and I don't want any problems on the street with upgraded rotors and pads as a result of not enough heat needed to stop well. Squeals? I could care less.
But wait, the brakes will be burning up at the track and to change them at the end of the event wouldn't be fun. Guess I'll set up the car's brakes at home before I go to the track and at home when I get back, depending on if it is local or a cross country event. Lots of thinking....too much for a Monday.

Thanks,
Andrew

 

[Jim Hodel]

I don't know the brake proportioning on the Z28. It has PBR single piston calipers in the rear. I suppose they could be better then the stock rear Viper calipers and contribute more to the overall braking. The Z28 had single piston cast iron calipers in the front, which were horrid.

I did flat spot a front tire at Thunderhill using the stock system and Porterfiled R4s, Motul 600, and air deflectors. The tire was ruined for sure. I have not flat spotted a tire yet with the upgraded front system, but that doesn't mean I won't.

I'm sure I can lock up the brakes if I stand on it.

Jim

 

[Richard K]

It's great to be able to read some of these responses on this subject from the people who really know of what they speak. I guess after reading this however I was a bit confused and have a question... Not considering the financial aspects, is there a benefit to utilizing an upgraded or big brake package on a Viper that is driven predominately on the street with only perhaps 1 or 2 track events a year? It seems I've read that without enough heat built up in the pads, braking could be less effective than a stock setup. Would one get any benefit of using say EBC greens on a big brake package on the street or would there be no difference from the stock rotors and calipers?

 

[Andrew2KRT10]

Richard:
EXACTLY what I am concerned about. This is definately the place to find out, plus wait till you start to get all the personal e-mails and the wealth of information. Street / 3-4 road race event per year combonation. That is what I need. I am open to all options. A lot of info already. I'll be doing alot of reading and thinking. No rush.

Thanks
Andrew

 

[K Adelberg]

Best advice is this!!!! There is some great information out there and also in the archive posts. DO YOUR RESEARCH! I did not initially and chose the SLR Brake System from Sean Roe at Roe Racing. Many of you are well aware of the story. I have spent close to a year with nothing but disappointment and aggravation. I finally had to look for other options and chose the Stop Tech System which has proven to be an excellent choice.

 

[Steve Ferguson]

Team Viper tested cross-drilled rotors about 4 years ago. They did not improve stopping times and provided far less durability that the stock version. FYI

 

[Chuck 98 RT/10]

Wouldn't the tires ability to grip limit the advantages of a brake upgrade? For example: Michelin vs Hoosier vs Slicks. The greatest brakes in the world wouldn't stop a bicycle tire any better that a stock setup would it? If true, then after certain brake upgrades the tire eventually becomes the weakest link. Also, wouldn't locking and flat-spotting the tires indicate that there 'might' be plenty of brake but not enough tire?

Just wondering.

 

[luc]

Richard,

"Race" pads will NOT work on the street.
Their coefficient of friction is designed to work only when they are warm/hot.
On the steet the problem would be exactly the opposite than on the track.
How to keep your brake hot compared to how to keep them cool.

That said, if you have a WELL designed set-up with bigger rotors etc,you can put street pads on it and have better brake than stock.
By the way,the reason than bigger (larger OD) rotors brake better,is due to the leverage effect.
Same than in a breaker bar,the longer the bar, the less effort is required for the same work (torque).
Consequently they will also run cooler since than for the same braking,you need less torque(friction in his case)

Tires,street/Hoosiers/Slicks impact/relation to braking.

For this one we need to separate braking system betwen ABS and non-ABS brakes.

The most important part of a braking system, beside of course being able to stop the car without fading,is what is called "brake modulation" or the ability to modulate the braking effort,often time what we call "pedal feel".

As we well know,and the idea behind ABS ( which is not a new idea since it was 1st used on planes back in the 50)is that maximum braking happen just before the wheel/tire lock.
There is some exception to that,as for example in deep snow or gravel where a non-ABS car will stop faster than an ABS car due to the fact that in this case it is advantageous to lock the tire because a locked tire will "push"and create a little mountain of snow/gravel that will help stop the car.

If you have such a powerfull braking system that you are loocking (in non ABS cars) the tires,it is because brake modulation is not optimized.

Why is is true that the tires are the final limit on how much braking you can do and of course slicks can deal with more G forces than street tire,braking is like horsepower or money, you can never have too much of it or as I like to say, Too much is barely enough.

To go fast you need to be able to brake very hard,at the limit of locking the tire,and use the brakes for weight transfer.
If you don't know how to use brakes for weight transfer,you car will NEVER handle to it's maximum.

If you lock the rear,a proportioning/bias valve is what is needed to adjust the line pressure to the rear.
If you lock the front,you should try a slightly smaller master cylinder bore that will give you a softer,easier to modulate brake pedal with more travel and consequently a better "feel" and a more precise relation between pedal and brakes.

Luc.00GTS

 

[luc]

Paul,I am racing at Thunderhill this weekend but I am going to Buttonwillow with Green Flag on nov 23/24.
Hope to see you there and have fun in Vegas.

 

[ntmatter]

Getting back to braking, I'm currently running stock rotors, Motuls, and "P" air deflectors. For 3-4 track days per year, is it worth investing in the stop-tech rotors? Also, what is the point of using a turkey baster to replace the fluid on the top of your brake reservoir? Wouldn't the really hot and/or contaminated brake fluid be the fluid at the end of each brake line? How much would a recirculating setup be, and how tough would it be to install?

 

[PMUM]

I put a gazillion track miles on my old Viper with stock brakes and didn't run into too many problems. You've just gotta bleed the fluid at least once per day, use decent race pads (Hawk, Porterfield R4s, EBC race pads, etc), Motul 600 and you'll be OK.

Porsche deflectors are certainly required if you don't run anything but getting a lot of air to the brakes is by far and away the biggest advantage you'll have. You've gotta find a way to route large tubes into the middle of your rotors. All of your parts will last longer and the car will be safer if you stay out too long. I'd much rather have a stock system with a ton of air than an aftermarket system with just deflectors. Of course the best bet is to have both, but the stock system is more than adequate with some ancillary work.

Keep an eye on the cracks in the rotors. I've cracked quite a few all of the way through and was very lucky not to have them grenade and take out the suspension. It feels exactly like a flat spotted tire when they've cracked only it goes away when you get off the brakes. The most important thing I've learned is to avoid staying out for the full session if possible. 30 minute track events are far, far too long to run a Viper full speed without at least a few laps with no braking to allow them to cool off.