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Hey guys,

I'm building a 71 Super for auto-x (see signature) and I've run into a bit of a problem regarding modifying my brakes.

I was looking at competing in the STX class which allowes suspension modifications and minimal engine modifications (exhaust change and air filter). The reason I chose the STX class is because they allow drum-to-disk changes.

I started thinking about when I move up to a higher class down the road and I noticed what I thought was a flaw in the rules. The Street Prepared class and Street Modified classes don't allow drum-to-disk changes. So I emailed Doug Gill who deals with rule clarification and he said it wasn't a mistake. He explained how the racers in the SP and SM classes wanted rule stability and blah-blah-blah. If I wanted to race STX then move up a few classes while keeping my front disk brakes, I would have to run in the Prepared class

So now I'm torn. I don't see the point of upgrading to disk brakes then downgrading when I move up a class when I want to go faster. This makes no sense!

Does anyone have any ideas or suggestions?

This, too, was my dilemma. But I wanted to go into street prepared, so I chose to stick with drums. When I decide to move up classes, I'm skipping prepared and going to modified or street mod 2. Prepared looks more expensive to compete in than modified because the rules are so tight that you have to spend a lot of money to fine tune your car.

Good luck

libila wrote:The Street Prepared class and Street Modified classes don't allow drum-to-disk changes.

HUH?!?!?

the 2004 rule book, Street Modified, Section 16.1 A states:

"Brakes, including calipers, caliper mounts, disks, drums, lines,
backing plates, pedals, boosters, master cylinders, handles,
ABS systems, proportioning valves, etc. are unrestricted. A
functional, redundant emergency (parking) brake must be present."

where does it say drum-to-disk changes are barred?
(not trying to be difficult, just want to know where it says...)

14.11 STX
7. "...Brake rotors may be replaced with any rotor of equal or larger
diameter made from a ferrous or aluminum alloy. Calipers are
unrestricted, but must mount to the original attachment points.
Drum brakes may be replaced with disk brakes of a diameter
equal to or greater than the inside diameter of the standard
drum part. Brake backing plates (dust shields) may be modified
the minimum amount necessary to accommodate allowed
alternate rotors and calipers..."

Even Doug Gill, who is the Solo Techinical Manager, said, "...drums to discs is not allowed in SP classes. It's one of those things that's a holdover from the "old" Street Prepared rules that doesn't match the newer Street Touring allowances." That is straight out of an email he sent me when I asked this question.

I understand where you got confused gcorrado, because I was under the same impression as you. But I was corrected by "The Man" so it must be so. One would think the word "unrestricted" would hold it's literary meaning but...

Perhaps the wording is bad or there is a mixup. I'm going to start off in STX for now and work my way up after that. I'm not going to complain because it will still be fun!

This is more common than you might think... a lot of sanctioning bodies are going through this phase of 'self governing classes' where a specific class or group of cars gets together and sets their own rules.

For example, in VARA, the Formula Ford and Formula Vee drivers all banded together and wrote their own rule book, somewhat based on SCCA and somewhat based on the expenses involved in maintaining a vintage race car - but they all agreed to it - so those are the rules.

Like most clubs, it's about the members. If you can get enough in SP to agree, I'd bet the rules would get changed. I know that may not help you now, but that is how it usually works....

okay so let's be super clear.

STX definitely DOES allow drums to disks.
14.11.A.8 explicitly mentions drums to brakes.

SP definitely DOES NOT allow drums to disks.
15.6.A doesn't mention rotors or drums at all
15.6.B says rotors may only be replaced by those of like size

this is all pretty clear (if dumb).

but what about SM?
16.1.C "brakes, including ... disks, drums ... , are unrestricted."

and you said Doug Gill (who i've talked to before also) said,
"...drums to discs is not allowed in SP classes..."

i fully understood before this conversation started that
you couldn't go drums-to-disks in SP. but Street Modified
and Street Prepared are very different.

did Doug Gill explicitly say,
"...drums to discs are also not allowed in SM classes..."

(i'm really interested in this because i went to SM precisely
because it was on of the only places i could go with disk
brakes and engine mods.)

thanks again for the useful discussion.

Yeah, you can do drum to disc in street mod. Just because Street Prepared, Street touring (X or S), and Street Mod all have "street" in them, doesn't mean they have anything in common. Street touring and Street mod were designed for the fast and the furious crowd to get more people coming to events. Street mod is very similar to regular modified except engine parts (mainly the block) need to be of original manufacturer origen. (there are a few other differences, but this is the main difference between modified and SM)

If you want to put a Type 4 motor in your car, you can go to street mod class. If you want to put a rotary engine in your car, you HAVE to go to modified.

Street prepared and Street mod aren't really connected to the Stock class, Street prepared, Prepared, Modified heirarchy...they're off on their own.

Nick

just to quadruple confirm...

i posted this question on the scca solo forum

drums -> disks allowed?
SP - NO
STX - Yes
SM - Yes

Doug Gill himself responded and confirmed that this is the case.

WHEW!!! (i was scared there for a minute.)

so libila, when you wrote:

libila wrote:The Street Prepared class and Street Modified classes don't allow drum-to-disk changes.

you didn't have it quite right.

The Street Prepared class doesn't allow drum-to-disk changes.
...but...
The Street Modified classes DO allow drum-to-disk changes.

So, this really makes SP a very difficult class for us to survive in.
SM2 is where i run, but i'm nothing like competitive. : )

My mistake, sorry!

It looks like I've got quite a leap in classes when I decide to move out of STX.

just curious...

...since disc brakes came stock on beetles of all variants in many countries other than the US since 1967.....what exactly is the problem?? DO you have to prove that your beetle was one of the multitude produced *with* disc brakes...or do they have to *prove* it wasn't?????

It was my understanding that as far as the SCCA was concerned, the car had to be sold IN THE U.S. with disc's for disc's to be allowed in regional or National competition. The reason the Treuhaft Superbeetle was allowed to run disc's in the U2.5 Trans-Am (and why Treuhaft choose a Super over a Standard) is the Trans-Am was considered an International Professional series, which was then 'influenced' by the FIA's rules for that group of cars.

There was another Beetle (a Standard) running in the 72 U2.5 Trans-Am that did score points at Mid-Ohio, and it was using adapted Porsche 356 drums if memory serves.

ericsbracer wrote:It was my understanding that as far as the SCCA was concerned, the car had to be sold IN THE U.S

yup, that's it.

IIRC Superbeetles WERE ALWAYS available in the US with front discs.
It was an option, and not uncommon parts in junkyards.

My son just picked up a pair of steering knuckles/brakes at the last Texas bug-in for $75 at my insistence. He has a 71.
(Yes, they are the right ones)


The SCCA can't argue with factory parts and option lists.

OTOH, they aren't 944 brakes, but STILL beat the drums.

Disks were available on ghias, though weren't they? If you start with a ghia with factory disks, can you upgrade to 944 disks?

HUGE brakes on the front and stock on the back, even IF "legal" are probably an extremely bad idea.
It's all about balance.

Example--- I put BMW 2002Ti brakes on the front of my 914, changed to the 19mm master cylinder.
The car was UNSAFE---Fronts locked LONG before the rears grabbed well even, ditching the proportioning valve helped--very little.
Pulling up to a stoplight was embarrasing a few times, fronts hard locked, rears still rolling.
(stock rotors etc)
Note that the 4 piston BMW brakes are not really to be considered HUGE, as the 944 ones probably are.

To restore a good brake balance, I put the old stock 914 front calipers on the BACK.
Yes, I have no parking brake. No, I don't park on hills.

But it stops great, wet or dry, tires being the limiting factor now.