Brake Rules in Prod
- Thread starter Brett W
- Start date
Matt Blehm
Moderator
Well that's partly my point.. why allow larger brakes on a car saddled with 13" wheels that can't do anything about the brakes?
My perspective is that all cars should be allowed decent brakes- different sizes based on EP/FP/HP possibly- and then a box rule for wheel & tire size that would allow the specified max brake size to fit.
My perspective is that all cars should be allowed decent brakes- different sizes based on EP/FP/HP possibly- and then a box rule for wheel & tire size that would allow the specified max brake size to fit.
Chris Schaafsma
Well-known member
It is more complicated than just brake rotor diameter. The 9.4 VW brakes work fine. The solid rotor 9.4 VW brakes work fine, even on an FP car going into Canada corner. Use the right pad, and if needed use the right ducting (I don't think Chuck's F car even runs ducts on the solid rotor setup).
Now, given the allowance, I will take advantage and lose some unsprung weight, but I don't think that is the intention being discussed here. <-This is my whole point of concern. Car by car as needed might make sense, but opening everything up "because racecar" will cause problems you did not expect.
Don't worry about us little wheel 13" guys. Those little wheels also change the leverage ratio that the brakes have (if you run the short tire) for the better.
Now, given the allowance, I will take advantage and lose some unsprung weight, but I don't think that is the intention being discussed here. <-This is my whole point of concern. Car by car as needed might make sense, but opening everything up "because racecar" will cause problems you did not expect.
Don't worry about us little wheel 13" guys. Those little wheels also change the leverage ratio that the brakes have (if you run the short tire) for the better.
WOAH, I am not talking about a class re-write. Prod isn't bad the way it is, just some parts of it are stuck in the 70s. Brakes and carbs. I know of one FP class racer who has had to remove his fuel injection just to go backwards to carbs but that is another conversation.
I am simply saying if we are building race cars awesome, build race cars with race car brakes. I already have a 11.75 x 1.25 rotor and Superlight II caliper setup that fits under the 15in wheels I am running using a stock Honda Upright. (yes I know not prod legal). I certainly can't justify going backwards to stock brakes, knowing the current engine kit will support over 400whp. However when I quit doing TT and such I would like to move the car into Prod or ST as both classes seem to be healthier than GT3.
I will need some help with the writing of the rule, but I bet I can come up with a workable rule proposal. (not sure what to do with it after that though). :ask:
Chois, you have kinda highlighted one of the problems that got Prod to the point is is currently. Ruling on a car by car basis and you have some cars with great brakes, big carbs, special heads, etc. Fix the problem. Everyone gets brakes of x size and four piston calipers. You lose some unsprung weight, gain some braking ability, keep the brakes alive longer and keep costs in a reasonable range without creating an uneven playing field.
I am simply saying if we are building race cars awesome, build race cars with race car brakes. I already have a 11.75 x 1.25 rotor and Superlight II caliper setup that fits under the 15in wheels I am running using a stock Honda Upright. (yes I know not prod legal). I certainly can't justify going backwards to stock brakes, knowing the current engine kit will support over 400whp. However when I quit doing TT and such I would like to move the car into Prod or ST as both classes seem to be healthier than GT3.
I will need some help with the writing of the rule, but I bet I can come up with a workable rule proposal. (not sure what to do with it after that though). :ask:
Chois, you have kinda highlighted one of the problems that got Prod to the point is is currently. Ruling on a car by car basis and you have some cars with great brakes, big carbs, special heads, etc. Fix the problem. Everyone gets brakes of x size and four piston calipers. You lose some unsprung weight, gain some braking ability, keep the brakes alive longer and keep costs in a reasonable range without creating an uneven playing field.
JasonIsley99
Well-known member
Brett W":3qyopl6s said:
You may not realize, but that is in fact what you are talking about. It may be stuck in the dark ages, but the brakes are one of the few items that separate Prod from GT/ST. If you are going to change the brakes you have to look at all the unintended consequences - wheels/tires, class balance, etc.
Correct me if I am wrong, you have not even built a your car for Club Racing yet? And yet you are suggesting a category with a vested group of drivers make a change that makes it easier for you to transition in? Seems like if your car is not done you still have choices, and ST might be a better fit for you (and if your car is capable of 400hp it probably does not fit in any Prod class anyway). You cant justify going backwards, but have no reservations about having every existing car buy and fabricate a new braking system. Some cars make power, some handle, some have better brakes, you pick your poison. If you want more allowances there are other classes for that.
I agree that just opening up the brake rules would upset the apple cart in ways that no one could predict.
Maybe someone that knows how to setup one of the surveys on this forum could do so with the choices of opening up the brake rules to ferrous rotors and up to 4 piston calipers on all cars or alternate brakes on a car by car basis. I would be curious to know just how other people feel about this.
Will Perry
Maybe someone that knows how to setup one of the surveys on this forum could do so with the choices of opening up the brake rules to ferrous rotors and up to 4 piston calipers on all cars or alternate brakes on a car by car basis. I would be curious to know just how other people feel about this.
Will Perry
Jason@SportsCar":1dkf9rp3 said:
Why should brakes be one the separators between those classes. If an outsider looked at Prod and GT they would see the main differences are aero, induction (to some degree),tube chassis and Brakes. The wheels for GTL and GT3 are pretty much the same as you will find in FP and HP. EP obviously now gets up to 18x8s which is now allowed in GT as well using the box rule with a weight penalty. If you change the brakes in Prod what does it really change. You can't fit a 14in rotor under a 15in wheel and the 13in guys won't be running any more than probably a 10in rotor but they can at least have better rotors, and calipers. There has been a huge discussion in GT about the 13 vs 15in wheel. Most of the GTL guys have decided to run the smaller wheels while the GT3 guys are sticking with the 15in wheel. I haven't seen anyone yet look to go to a 17 or bigger just because the brakes are available. For Prod why not just allow a max of 12.88in rotor and a basic four piston caliper. No one will be forced to change wheels if the rules don't change for wheel sizes. Besides you are still limited to what can fit under the rule required wheels.
Jason@SportsCar":1dkf9rp3 said:
I am building everything on my tub/cage/body to Production/GT chassis rules (no tube chassis). The brakes bolt onto a stock upright with an adapter bracket. The engine is the only thing that will spec the car out of Prod. However the D16A6 engine is legal in FP and all of my suspension components are prod legal. When I can afford to go to a full club racing schedule its a matter of changing the engine from a turbo charged engine back to a prod legal engine. Everything else is legal except the brakes. It just seems ridiculous to limit everyone in Prod to production calipers and rotor sizes (on the front only). If you are going to make the brake rules sorta open why not go ahead and open them up completely. Prod allows me certain freedoms that ST doesn't, however the availability of more modern technology in ST is very interesting.
I have been told before that "such and such" car has plenty of brakes in Prod form. Not everyone will change over, nor is anyone required to change over. I doubt the HP guys will go to great lengths to swap over to big brakes, but I fully expect the FP guys and the EP guys to go there, it a natural progression. This sounds like the same argument used against the aftermarket connecting rods. Several of the old guard claimed their equipment would be obsoleted overnight because of this change? How are the Prod participation numbers this year so far?
Plus it will bring more people to the class and will make the inevitable combination of GT/ST/Prod go smoothly. :twisted:
I kinda have to ask the Prod folks, if you distilled it down, whats the difference in STU and the Prod class? Aero, and engines. They have many more limitations on engines, but can do engine swaps and such, have to run DOTr tires, and don't have quite the freedom to suspension wise that the full prep Prod Cars have. Since Most new Prod cars are Limited Prep short of slicks (and possibly age) why wouldn't those cars chose to go run STU instead of prod? If you look at the results from the VIR Majors the STU times and EP/FP times are very close. Seems like the different approaches to building those type cars don't really make a difference in times. I would wonder what is driving the participation numbers for STU and Prod?
James Rogerson
Well-known member
The only true way to reduce equipment costs is to use the most common products. Allowing 15x7 wheels at 12.1 lbs. minimum weight and open brakes would meet that cost reduction goal. Just because you can doesn't mean you have to or should. But if you're really concerned about cost, that's the way to go today.
James -r
James -r
JasonIsley99
Well-known member
Brett W":mkhqugqi said:
I find it hard to take you seriously, you are ok with replacing the motor when you are ready to come racing, but its to big of a step back to change the brakes. :lol: Chances are at some point you are going to have to buy rotors and pads no matter what, so you are a set of OE calipers and anchors away from Prod legal brakes. You can probably even find someone that will buy your fancy brake kit.
Your proposed rule change is a potential cost for every existing Prod racer. Need them or not I know I would go for an aluminum caliper - which cost money, as does fabricating the mounts, and a new master cylinder.
blamkin86":3co44352 said:
No, just saying a max size for all of Prod. You don't have to run that, you won't fit that under a 15in wheel, etc. I'm just saying. The S2 currently has an allowed 11.73in rotor. So sure they could run the 12.88in rotor even though they have an 18x8in wheel allowed. The Lotus wouldn't need a rotor that big and I doubt the competitor would want to take the weight hit of a rotor that size. Also the Super 7 is limited to a 13x7in wheel. That would be the limiting factor for the brake size. Just thinking about a maximum size for the whole group.
The price of consumables goes down as your rotors last longer, your pads run cooler because there is more pad surface area, the common pads are very inexpensive compared to custom one off pads for you production applications, etc. Plus they are readily available. Beats having Carbotech make up a custom set of pads.
The thought was to select a maximum rotor size for Prod and limit the caliper to a four piston reasonably priced caliper. Put a cost cap on both pieces and leave the rest of the choice up to the competitor.
For example lets say rotors are now more than $300 a piece and calipers are no more than $600. Just tossing a number out there for discussion sake.
Jason@SportsCar":2ngl5y66 said:
I fully expect this turbo engine to last for a few seasons of TT, turbo D16s are not exactly durable engines. Plus its not legal for any class but the SEDIV TT SU class or SPO. I have no desire to run the car in SPO. Also I already have the engine and the package has proven itself in the original iteration of the car. So yes, swapping an engine is not the end of the world as it is something I expect.
Like I mentioned in the beginning of the thread, the TA2 cost cap rules raised an interest thought in regards to the potential to finish opening the Prod brake rules up. The rules already allow everything but custom front calipers and a generic size rotor. Why has Prod stopped short of upgrading the rest of the brake system?
So.... The upshot is that we should change the rules to some relatively healthy classes like prod to be more like a class that allows the same but is unhealthy... Did ya ever wonder if perhaps there is any causality, even slightly, between the two?
I was wondering when the first cases of rule change arguments that would bring together the prod and GT rulesets in an ad hoc manner were going to start popping up.
I was wondering when the first cases of rule change arguments that would bring together the prod and GT rulesets in an ad hoc manner were going to start popping up.
Greg Nagy":1r4u2f74 said:
I seriously doubt it was the brake rules that killed GT. However looking over the 2015 participation numbers STL is killing PROD and they allow brake upgrades:
http://crbscca.com/staffAdmin/points/pa ... pation.php
Otherwise the data doesn't suggest that Prod is any healthier than classes that allow brake upgrades. (except GT3) http://www.scca.com/clubracing/content. ... 470&tag=48
Even on a regional level the ST classes are doing just as well if not better than the PROD classes. Why do you think that is? If we leave off the tube chassis allowances and the aero what really separates Prod from GT anymore (besides brakes)? I notice out of the three PROD classes EP is the most heavily subscribed. Could that be the allowance of more modern cars? I don't have all the answers, but some of the "sky is falling" arguments just don't really seem to hold water in light of the participation data.
JasonIsley99
Well-known member
Brett W":2jhaehd8 said:
Its a shame participation numbers don't to tell the entire story... In the Western Conference we see about 50% of STL entries being actual STL builds, the rest are SM/IT/Prod cars double dipping - so none of them will be taking advantage of the brake allowance.
Tell me what benefit is it to Prod to have every car spend $1k to upgrade brake calipers (not to mention the people who have to buy wheels because the 13x6" they run does not offer enough face clearance for a 4-piston caliper)?
Aaron Johnson
Well-known member
weight reduction if run stock brakes? :doh:
Brian Linn
Well-known member
Having raced a few different prod cars over the last few years, I will say that the newer (does a 25 year old Miata or CRX count as newer?) cars have very good stock brakes. Also, it can be hard to find a variety of pads for a Lotus 7 - or even find out what the alternate brake set-up is*.
20 years ago when they allowed rear discs to replace drums, it was a revelation for me to work with a modern caliper. So we can put a racing caliper on the rear, but need to use the old POS caliper for the front. I think Harold was on here a handful of years ago arguing this same point.
If we are using the brakes as a competition balance, then maybe we stick to stock (or alt) rotor size and stock # of pistons but open up the calipers. But if there is a failure mode for a heavy car with small brakes (VW Scirocco?) , then it's beyond the scope of competition balance and becomes a safety issue. Maybe we need to go by weight - if your car weighs over X, then your max rotor size is y, if your car weighs under x then, your rotor size is y-1"... If some cars weigh so much they need vented rotors (I have no idea how to quantify the value of a vented rotor vs. a solid disc, or it's ability to shed heat) then we should look at that.
Just ideas, hopefully a springboard for better ideas. I don't want to see the 'balance" changed, nor should there be a need for everyone to have to upgrade to the latest super duper package. But it would be nice to have a caliper that is newer than 50 years old with a selection of pads. With the Miata or CRX, I wouldn't feel the need to change calipers if they were allowed.
*the Lotus7 lists an alt brake of "#OAOB 405/6 with a 9.0" front rotor". I asked Lotus guys, Triumph guys and Spridget guys if that part # meant anything to anyone. I couldn't find anyone that knew what that was. I did find that part # in the PCS in the 70's. It would've been great to get a Wilwood caliper and have been done with it. I realize this scenario is very limited.
20 years ago when they allowed rear discs to replace drums, it was a revelation for me to work with a modern caliper. So we can put a racing caliper on the rear, but need to use the old POS caliper for the front. I think Harold was on here a handful of years ago arguing this same point.
If we are using the brakes as a competition balance, then maybe we stick to stock (or alt) rotor size and stock # of pistons but open up the calipers. But if there is a failure mode for a heavy car with small brakes (VW Scirocco?) , then it's beyond the scope of competition balance and becomes a safety issue. Maybe we need to go by weight - if your car weighs over X, then your max rotor size is y, if your car weighs under x then, your rotor size is y-1"... If some cars weigh so much they need vented rotors (I have no idea how to quantify the value of a vented rotor vs. a solid disc, or it's ability to shed heat) then we should look at that.
Just ideas, hopefully a springboard for better ideas. I don't want to see the 'balance" changed, nor should there be a need for everyone to have to upgrade to the latest super duper package. But it would be nice to have a caliper that is newer than 50 years old with a selection of pads. With the Miata or CRX, I wouldn't feel the need to change calipers if they were allowed.
*the Lotus7 lists an alt brake of "#OAOB 405/6 with a 9.0" front rotor". I asked Lotus guys, Triumph guys and Spridget guys if that part # meant anything to anyone. I couldn't find anyone that knew what that was. I did find that part # in the PCS in the 70's. It would've been great to get a Wilwood caliper and have been done with it. I realize this scenario is very limited.
As a semi humorous aside, what is it about VW racers that seems to give them zero "stick togetherness"?
Bob Coffin (hi Bob) thinks the VW doesn't get brakes etc because of the money flow from Mazda etc. I think that VWs don't get "x" because any time anyone posts on here that the VW needs "x" some other VW guy (not always Chris) pops up immediately and says "no it doesn't, so-and-so's been winning races for years with bone stock x". The Mazda and Honda guys cut each other more slack IMO. VW guys must all be rugged individualists..
Maybe Chuck is so good he never brakes, maybe he slows down by throwing the car sideways like Don Barrack used to, maybe it's parachutes or magic, dunno.
Or maybe weight counts more than power, the HP cars are heavier....
If the VWs don't need alternate brakes (a 9.4" non vented rotor on a fwd (ie nose heavy) car weighing in some configs as much as 2205 lbs) then I'll go out on a limb and say that no Prod car has ever needed alt brakes. All the VW really needs IMO is the vented rotors off of other A1 chassis VWs in the same class, is that too much to ask?
Bob Coffin (hi Bob) thinks the VW doesn't get brakes etc because of the money flow from Mazda etc. I think that VWs don't get "x" because any time anyone posts on here that the VW needs "x" some other VW guy (not always Chris) pops up immediately and says "no it doesn't, so-and-so's been winning races for years with bone stock x". The Mazda and Honda guys cut each other more slack IMO. VW guys must all be rugged individualists..
Maybe Chuck is so good he never brakes, maybe he slows down by throwing the car sideways like Don Barrack used to, maybe it's parachutes or magic, dunno.
Or maybe weight counts more than power, the HP cars are heavier....
If the VWs don't need alternate brakes (a 9.4" non vented rotor on a fwd (ie nose heavy) car weighing in some configs as much as 2205 lbs) then I'll go out on a limb and say that no Prod car has ever needed alt brakes. All the VW really needs IMO is the vented rotors off of other A1 chassis VWs in the same class, is that too much to ask?
Chris Schaafsma
Well-known member
Good point Al, and not at all my intention. I just respond with examples that I know. The thread was about why we need to allow alternate brakes, and a car that know can stop in F (at a MUCH lower weight than the HP cars as you point out) was given as an example (solid rotor small VW brake). I figured it was assumed that the vented rotor HP VWs can stop based on recent history of Scirocco 2 and Golf 2 success in the class. If I hear something that I don't think is true being used as an argument to support making rule changes, I'll chime in with what I know.
As far as VW guys sticking together, from what I have seen, whenever someone racing/building a VW has asked what works, people are pretty open to sharing. For us it comes down to a few things - use the right pad (way more aggressive than the Hawk Blue -> DTC-70 or similar grade Carbotech, etc.) - run a spool/welded diff - put good ducting on the front if you still have issues. This assumes basic race prep items like a functional proportioning method to properly bias the front braking.
I did think all the VWs running the larger engine/heavier weight have the ability to run vented rotors. Is that not the case? Otherwise all the A1 and A2 8v VWs have the same front brakes already.
As far as VW guys sticking together, from what I have seen, whenever someone racing/building a VW has asked what works, people are pretty open to sharing. For us it comes down to a few things - use the right pad (way more aggressive than the Hawk Blue -> DTC-70 or similar grade Carbotech, etc.) - run a spool/welded diff - put good ducting on the front if you still have issues. This assumes basic race prep items like a functional proportioning method to properly bias the front braking.
I did think all the VWs running the larger engine/heavier weight have the ability to run vented rotors. Is that not the case? Otherwise all the A1 and A2 8v VWs have the same front brakes already.