Help with track car rules

[A Quiet Boom]

Hey all,

I've got this '73 shell that I bought from Shuie about 2 years ago that I want to build up into a track/street car. The look I'm going for is more track than street even though I'll likely drive it on the street more. I had a drag car like this and I know the downsides to driving a track vehicle on the street such as creature comfort etc. Those are the things that actually make the car fun for me. Creature comforts are for my daily driver Ranger, I want this car to be pure function.

Here are my plans so far,

C2 RS America body, G50 Trans, the 3.0 from my '66, fiberglass wherever I can afford it. No interior, just a cage, seats and guages. I have new 996 brakes that I've adaptted to Carrera suspension.

Here are my problems, I want the car to be able to pass tech for as many forms of racing as possible. I've never raced on a track before so I want to do the car right from the outset. When I built my drag car it slowly progressed from a 14 second bracket car into a 10 second Super Pro car and the result was poor overall (like I should have started with a hardtop instead of a T-top). In short I want a car that I can grow into and add more power as I become a better driver and as funds allow. The most important thing is it has to be fun. The car as is has no gas tank and the rusted rear firewall has been cut away and replaced with aluminum panels.

I want a full cage in the car that also ties the front and rear suspension together and while I'm an experienced welder/fabricator I have a friend who is certified to do the cage welding. In some cases the rules state that the cage may not penetrate the firewall so I need to know how to attach to the from and rear shock towers and remain inside the rules. I also want a center fill gas tank and want to know if I can modify a stock tank for center fill and still pass tech.

Obviously I'll start out with drivers ed events and hopefully progress to high performance driving, possibly eventually moving up to class racing. Since the engine is already larger than stock that's going to be tricky with respect to rules and regs.

I'd love it if there was someone in the northeast Ohio area that could meet with me and guide me, and I'd be willing to pay a consulting fee. I'm an accomplished hobby machinist and have at my disposal a full machine shop including CNC as well as a welding shop. I can rent or borrow a tubing bender for the cage and I'm buying a sheetmetal brake and possibly an iron worker. A big part of the fun will be actually building the car as it will bring all of my hobbies into one. I have friends to help with various other stages on the car including wiring, suspension, fuel, bodywork and paint.

I'm also on a budget with more time than money so anything I can make myself will mean less cash outlay. The only time table I'm on is the fact that my '66 is rapidly approaching the point that it will need another repaint if I'm to continue driving it, I plan on selling it as an empty shell when this project is complete.

Any and all suggestions are welcome except dumping money into the '66 to make it track worthy. At the end of the day I want a good looking track car that I can drive on the street once or twice a week.

[A Quiet Boom]

I should add that since I'm a rookie and I'd like to get some track time under my belt I'll likely install shoulder belts in the '66 and participate in a few DE's next year, hopefully there I can gain some ideas for the buildup of the '73.

[Bill Verburg]

You really need to find a rule book to read, reread and then read again. From the description of parts you are going to end up in one of the higher (more expesive) classes.

To keep costs under control, I would build something like a '73 2.7 Carrera RS l/w clone. You can do all sorts of fun close racing w/ one of those.

[A Quiet Boom]

Bill,

Make that rule books as in plural. I want a car that passes safety tech for NASA, SCCA and IMSA. I don't particularily care which class it falls into as I'll be doing DE's and high performance driving at least for several seasons. I just want a car that at the end of it all is ready for class racing if I so decide.

[North Coast Cab]

Chris,
Download the PCA Club Racing rules at www.pca.org as well as the Nasa Club Code Regulations at www.nasaproracing.com as a start
Tons of guys run their cars in both as well as SCCA. The biggest tech issue is the cage, but I know once you see the rules it will all make sense. Also, I'd suggest you take a run to the NORPCA Mid Ohio DE in three weeks and take some pictures.
Beyond that Bill is right about the car class. In Nasa it's a weight to HP/TQ scale, but in PCA it's much more strict. On the lower end of the HP scale you get a lot more DIY guys and at the higher end you're not only competing with some big $$ guys, but also some much newer and more technical cars.
I'd put a list of needed components together and buy them as they arise used.
John

[Don Plumley]

There's a lot going on in this question. It's a little challenging to parse down into something that makes sense, but I'll give it a go.

I went through this process last Fall. I decided that I wanted to dedicate a car to learning how to drive on the track. But I was both unsure if I ever wanted to W2W race, and in any case, I knew that would be years away. So I built a car that was safe, stable, and a good platform to lean in - if not too capable.

For most organizations, a DE car is a street car that is safe. If you show up with a highly modified car, you will then be placed under more, not less, scrutiny. So Bill's advice about looking through the GCR's of the various organizations you want to run with makes sense.

But you are really challenged designing a race-ready car now unless you know exactly with what group and in what class you'd like to run. A lot of this depends of were you live, what groups are active, and within those groups, what classes are competitive/interesting/don't require huge checks to be competitive. In our area, Toyo spec cars are popular and competitive and you don't need to spend a king's ransom to run. But in the GT2 classes in POC, PRC - you are competing with factory cup cars and guys with bigger wallets than you can imagine.

With just 12 track days in, I'm starting to run a couple of TT's, and my car gets classed. Because it's fairly well-equipped, I end up competing with people that have years of experience and my results are as you might expect. With what you are talking about building, you'll be running against folks that are trailering in a full-blown race car. I don't know about you, but I don't really like being the slow guy in the group.

Now I understand it's really fun to plan and build a full-cage, empty shell race car. And if you do it understanding that a) you won't be competitive for a while; b) you might end up spending another large lump of money to bring it into a specific class spec; and c) it will still be a compromise over stuff that is getting trailered in, then eyes open, go have fun.

But you have made a great leap over people that get sucked into making a track car from whatever they started running, as opposed to starting with a platform car and focusing on what you want to do. So let's plan out a strategy.

A full cage is necessary for W2W. It is likely overkill for DE's and moderately unsafe on the streets. If you go full-cage, you'll want to abide by the most stringent GCR's you can find (PCA or SCCA for example). This will govern tube size, mounting points, side protection, firewall penetration, etc. One of the challenges of a full cage is the type of side impact protection may require you to gut your doors, which means you lose your windows, which means you can't drive it on the street anymore. I set my roll bar up to be easily extended into a full cage, but will wait until I decide I want to go W2W with this car.

Once you've gotten through the cage, you'll focus on suspension - this is where money is most intelligently spent. Again, class rules start to really matter here.

As an alternative, you can create a frankenstein track beast, and given your engine, full cage, etc., just run in Exhibition class and stick to lapping clubs. Tons of fun.

Anything other than a full-blown race car is a compromise. I've chosen to leave in AC and Cruise control for my to/from track drive. As Bill suggested, I think you'd have a lot of fun with a 73RS track car with a simple roll bar and inexpensive suspension upgrades. Then when you figure out if you want to run W2W and pick your class, etc., then build a car that exploits every advantage you can without getting into a non-competitive class.

Sorry to be so rambling, if you have some directed questions I'll do my best. You might also want to have the moderators move this to the DE forum where you'll get more useful advice.

[Bill Verburg]

The nice thing about the 2.7RS l/w is that many of the organizations wrote their rules around that car.

[A Quiet Boom]

So how does a versoion of the 2.7RS with a carbed or EFI 3.0 fit into the works? Am I limited to the RS bodywork? I like the look of the RSA but realize that those cars came with a 3.6 which I can't afford right now. All I need are front and rear fiberglass as I already have the lights and reflectors as well as tail.

The cage is going to be key as the car will be completely stripped prior to installation and I plan to paint it in that condition. I don't want to tear down later to add more cage unless I have to. I'd like a simple cage that ties the front and rear suspension together.

John, I've got the NASA rules already which is part of my frustration. Particularily the whole fuel cell issue. The car doesn't have a tank and I want to go with the center fill look. It's not clear as to whether I can modify a stock tank for centerfill or not. The car not having the orignal rear firewall may also be a problem even though I've seen track cars with removable sheet metal replacing the rear firewall. Jack Olsen's car has the seat area cut out but the upper firewall intact.

Don's pretty much hit my ideas right on. A car to learn it that can be moved into class racing should time, driver skill and money allow. If I moved to class racing it would only be local tracks at least for 3-5 years. I'm just too busy with a growing business to be driving around the country and heck I might find I'm a far better mechanic/fabricator than driver. When I drag raced I spent a lot of money on making the car faster until someone pointed out it would be cheaper to make me faster. I stopped wasting time and money on that sport before I ever got really good behind the wheel.

[North Coast Cab]

Chris,
You do not need a fuel cell for Nasa, but it is highly recommended. Also, you don't have to buy a $2000 one designed for the 911. Many of the guys use a generic one which cost around $450. The center fill is cool, but will add a ton of time and cost to your project. Maybe you could add it down the road.
As I mentioned, Nasa doesn't care what our car is made of or looks, but only the Wt/HP ratio. PCA is much more strict and when you looke at their car classes you will see Stock, Prepared and GT/GTC. Once you touch the bodywork you're most likely in GT which is basically wide open and classed based on the engine block.

John

[A Quiet Boom]

John,

Thanks, actually the only sanctioning body I'm not interested in much is PCA. I just don't see a lot of fun in racing a bunch of other P-cars. To me it's kinda like the 5.0 Mustang series, I got bored with that real quick when I drag raced. I had a lot more fun beating the big block Chevy and Chrysler guys with my "little" 410CI stroked 351W smallblock!

I like racing like the event I went to see you and Pete Brown run in at Mid Ohio, lot's of different makes.

As for bodywork it's already been touched since the car came with SC flares and there's the issue of no factory rear firewall.

I'll have to make a point of going to Mid Ohio in three weeks. From what I can tell I've got a lot to learn before I fire up the welder as they say. I guess I'm just antsy to get started now that I have the floor space to do the car (we got that building next door) and I'll have some time this winter to work on it.

[Don Plumley]

If you like the look of the RSA, sell the 73 tub/motor and buy a beat 964. You get a G50 and a 3.6, the right bodywork and a coilover setup. A 964 would make an outstanding platform for a safe, fun DE car. It responds well to weight loss, has good brakes, yada yada.

Then when you've figured out what you really want to do, sell it and build a class-specific monster - or use it as a platform.

If you stay with the longhood, a carb'd 3.0 is not all that uncommon in various classes. You'll struggle with PCA once you move out of prepared though. If you want to have center fill tank, make it look more like a cup car, etc. - then focus on the lapping clubs for now and know that if and when you want to race, you'll be changing a lot of stuff.

[A Quiet Boom]

Don,

Good suggestion on the 964 with one little problem, hehe. I can't seem to leave engines alone and the '73 is emissions exempt here in Ohio. Believe me I've thought of that though, a 964 would make a lot of things easier. As it sits the car has no front fenders, no hood, no bumpers. I plan to take the fiberglass impact style fenders from the '66. The '66 has the narrow IROC front end which I'm bored with. Also I'm not big on brand specific racing of any kind. I won't be doing PCA races. I've also considered a ratted out 993 as a starting point be again we get into the whole need I have to screw around with engines. I was born that way, can't help it LOL .

I know I don't need a fuel cell for the car but I figure since I don't have a gas tank....

Cup car, you've hit the look I'm going for. Remember I'll be driving on the street on occasion and there's nothing neater than driving a "racecar" on the street IMO.

[Grady Clay]

Christian,

I will second what Don & Bill have to say about early cars. Yes, a 964 might be a consideration. So should a 944 class.


The choice you need to make is weather you want to go “balls-out” toward one series or build a flexible compromise where you can successfully run in several series. Keep in mind the “compromise” won’t have you at the competitive edge anywhere. That doesn’t seem to be your goal now.

Here are three of the most important rule books in .pdf format. Note that these are all 2006 and the 2007 should be available very soon. Most clubs have the 2007 Proposes Rules already posted.

The SCCA General Competition Rules & Specifications (GCR).
The PCA Club Racing rules and Parade Competition Rules (CR_Rules) and (PCR).
and
The Historic Sportscar Racing rules (HSR).

I recommend you find your local vintage racing group also. Most vintage racing clubs accept each other’s rules, licenses and car eligibility.

I encourage you to join all these organizations now, go to events and get to know the people. You will find fun everywhere. The PCA DEs should be your first exposure (and great learning).

You should start collecting cars and parts. To do this economically, you need to become somewhat of a “junk 911” entrepreneur. Inside storage is the issue. If you buy right, you can always sell right.


Now, considering your ’73 911.

Before you start anything you should thoroughly assess the rust situation. A 33 year old rusty tub will literally fall apart if called upon to withstand the rigors of racing. Even in rust free condition it needs significant attention and reinforcement to maintain this use over the up-coming decades. If the chassis is worthy, the time to make everything right is now. Fixing it later isn’t an option.

An additional consideration might be to build a second one as a spare chassis. The additional expense and effort isn’t that great. Consider it money in the bank.

Your personal safety is paramount!

While the cage, etc. must meet all the racing organizations’ requirements, you can extend the safety quite a bit beyond their minimum. For instance the basic rules to use are the SCCA. Every other organization recognizes that as a “gold standard.” You can use 4130 alloy tubing (lighter) but use the spec for the next level heavier car (much stronger but brings you back to mild steel weight). Read the rules carefully and submit your proposed cage to SCCA and others in advance of fabrication.

You should have both the driver and any passenger equally protected (you can always remove the passenger seat and other equipment). Have the cage extend into both doors. Position the seats closer to the tunnel (even if you have to move the steering wheel mounting over). Use the HANS device and lots of appropriate padding.

Use a very large (not minimum) fire suppression system and have spare Halon bottles (I like to use the spares as pit extinguishers).

Mount the smallest fuel cell necessary for your events. Check HERE for mounting ideas.

The suspension and all the other race 911 stuff are fairly conventional. There shouldn’t be too much need for inventiveness. I recommend you study and photo every successful 911 race car you can find (and even the lesser ones to know what not to do). Your 911 should be a collage of the best-of-the-best. That doesn’t mean in terms of expense.

As always with a 911, make everything as light and simple as possible. If it isn’t on the car, it doesn’t weigh anything. (The “accessory” that slays me is the hook to hang the helmet on. Not only is it scrofulous but it can also spear your hand in an upset.) What has to be there should be low and to the front. Include yourself. Mounting the seat low forces you to look ahead and not at the pavement in front of the car.

I recommend you start with something like a 2.2. Engines are easy. You can use a core 2.2T and simply add very high CR pistons, Nikasil cylinders and radical (935 Sprint) cams. Your (and others) skills can make the Zeniths work just fine. You can build from scratch 3-4 of these engines for the cost of one 3.x race engine. Start small.

I would make the chassis/suspension the best from the get-go. Having the ability to easily “tune” the suspension is the most important aspect of the car (far more than the engine). Having coil-overs; a selection of springs, shocks and sway bars will allow you to meet the needs at differing tracks.

Money well spent is the ability to re-gear your transmission at events. Again, consider the (sometimes outrageous) expense of racing gears an money in the bank. With practice and a helper, you can change gears between track sessions at many events. It takes preparation.


The best money will go to your ability to overcome any difficulty and keep going to events.

I recommend you go to every event possible in the interim. Help every racer and learn. Whenever someone has a problem, pitch in and help. Learn from their mistakes. That includes the extremes. In the process you can bring the expertise of professional level to the basic beginner. You get the experience and perspective with no cost.

Go to every DE and other event possible. Once you have experience, sign up to be an instructor. You will learn far more teaching than otherwise. Get together with others and rent the tracks for “test days.” This can be your most productive driving experience.

Be organized. Emulate Roger Penske (on a smaller scale). Remember, it is better to be a big fish in a small pond. The whole reason for this is fun. Keep in mind the adage; “How to make a small fortune in racing … is to start with a big one.”

Best,
Grady


Edit to correct link syntax.

[Don Plumley]

It's impossible to top Grady's advice.

One thing you said did strike a chord with me - "...there's nothing neater than driving a "racecar" on the street IMO."

When I started my project, I was looking at some pretty mean machinery - stripped out interiors, full cages, MFI. And thought to myself, "there would be nothing cooler than driving a racecar on the street." Tyson slapped me back into reality. He said, (paraphrased) "after a long day at a hot track, and then you have a 3 hour drive home in your track car. When you turn the AC on you will think you are the smartest person in the world." Add to that cruise control and a stereo and that's another reason I grin all the way home.

After tearing up the track for a day or two, the fun in driving a tightly sprung, bare cockpit track car home was spent on the racetrack. I would venture to guess that after a year of taking your car on the track, the joy of driving a racecar on the street will become a distant memory.

The racecar is a tool to deploy on the track. It is unhappy (uncomfortable) anywhere else. That's why I'm in favor of moderation - have a compromise car that is safe, stable and reasonable to drive home until you decide to go all in, and then build a no-compromises car and tow it in a trailer.

Don

[A Quiet Boom]

Grady,

Sounds like a wonderful plan. A bit out of my budget at the moment though. I do have indoor space and I can start (and have) collecting parts. I don't know about another chassis at this point though, remember my plan is to just have fun at first and MAYBE go class racing later. I love your suggestions about going to track days and DE's etc. very sound advice IMO. I could do a little work on the '66 to make it track worthy.

If I read right you're saying that an SCCA cage is the standard I should follow? 4130 tubing is on my list and it will be Tig welded by a professional. This is the only area on the car that I want someone else to do and I've got a certified welder as a good friend so it's a no brainer. From a rust standpoint the car is very good overall. All major rust has been addressed and I plan to go over it with a fine tooth comb. I also want to seem weld the chassis and reinforce wherever possible.

Now for an engine. No race only engines at this point, I figure the 3.0 with headers, mild cams and carbs will be more than enough power for a rookie as well as being dependable. My main concentration for now will be on suspension and brakes after addressing safety and structural integrity.

If I'm following you correctly then the first step is to go to the remaining events this year while getting my car rottiserie setup and the car on it. I should completely strip the car so I have a got starting point and can address any questionable areas at that time. Then based on SCCA rules as well as what I learn at track events I should plan a cage and submit it for approval. Once that's done I can paint the basic tub and go from there.

As for transmissions I have two 911 boxes and one 901 box as well as a shortcase G50. The 911 box has suited me well on the street but will it hold up to the abuse of a roadcourse behind a 3.0? Obviously the spares give me the opportunity to gear for different tracks down the line as well as be able to race rather than be home fixing a broken tranny. Since there is no rear firewall I'd like to make the section above the trans removable for trans repair and possible gearing changes.

This car will need to also hold up under aggressive street driving with the occasional stoplight to stoplight sprint which is a big reason for the G50 even though the un-modified 911 box has done just fine.

Gearing, that's an issue to address. With a full machine shop and local heat treating does it make sense to make my own gearsets for whichever box I select? My CNC is only monthes away from a 4th axis which would make gear making an easy endeavor. How about other parts, should I set myself up to make as much stuff as possible?

Lastly I love carbs, in fact I'm running modified Zenith's on the 3.0 but I'm also enamored by the ease of tuning that EFI allows and I'm capable of building IR throttle bodies. Is this an expense that is better saved for later or would the reliability and tunability of EFI be a better choice from the onset allowing me to hone the rest of the car as well as my driving skills rather than spend time tuning carbs.

Thanks for the links I'll download and read them when I get home tonight.

[A Quiet Boom]

Grady, thanks again for the links.

I read all three concerning rollcages and by far the SCCA one is the most detailed. The historic racing rules do not allow for attachement to the suspension pickup points, something I didn't notice in the other rules. Also SCCA allows penetration of the front firewall provided the hole is sealed and doesn't allow penetration of the rear firewall. I assume this is meant for front engined cars and is possibly reversed for a 911. Is there any way to clarify this? It's important as I need to know if I need to get replacement sheetmetal for the rear firewall. If I can't penetrate the firewalls can I put a plate on each side and terminate the bars at the plate. For example if I wanted to tie into the rear shock towers.

Of particular interest is the maximum of 8 mounting points, I have to assume this is to prevent attaching the cage to all the suspension pickup points as is common at least in the rear for drag racing. It appears I can strengthen the rear shock area and attached to it on the inside of the firewall. If I can penetrate the front wall then I can attach to the strut towers effectively tying the front suspension to the rear. NASCAR style door bars are recommended but this would mean losing the side glass so it's not an option for a streetable car, however it only seems prudent to run double side bars for both safety and rigidity. I'd do this in the NASCAR style without bending them out into the doors.

Is there any reason I couldn't run bars between the strut towers as well as forward to the bumper mounts to protect the front of the car as long as they are not attached to the roll cage?

Thanks for the tip on a non custom fuel cell, I will look into what will fit and what the cost will be. Center fill is just something I'd like to have but don't need to have. I wonder if a factory tank modified ala 911R would be acceptable.

I've also seen oil tanks mounted up front as well as batteries mounted in the smugglers box. What are the advantages of these mods. I'm assuming it changes the polar moment of inertia, is this correct? What is the downside to a front mounted tank?

Seems I've got a lot of "homework" to do. I definately need to get to some more races and bring a camera.

[A Quiet Boom]

Oops, forgot to reply to Don's comment. I still have my car trailer from my drag racing days and know full well how unenjoyable it is to drive back from the track in a racecar. I also know how much of a pain it is to get both you and the car home when something breaks. My plan is to tow the car to and from the track while enjoying the comfort of cruise and AC in my Ranger. That Ranger will easily haul the trailer and car BTW as I've comfortably towed at least 1000lbs more for greater distances. This way I enjoy a comfortable ride to and from the track and don't have to worry about getting a broken racecar home. Street driving the trackcar will be a weekend or evening thing only unless a client seems interested in a ride. As it is I only drive the '66 to work on rare occasions, prefering the convience of just hopping in the truck on most days. What ruined my drag car for the street was a full spool in the rear and too much power for anything less than DOT tires. The slightest hint of rain made that car feel as if you were driving on ice. Loud, rough riding, racecars are fun on the street on a limited basis, like when I feel like hitting some back country roads etc.