Not in the real world YET Steve except for about 100 CFD runs, of which about 90 were a learning experience.Originally Posted by S Lathrop
Not in the real world YET Steve except for about 100 CFD runs, of which about 90 were a learning experience.
Last edited by Jnovak; 01.14.14 at 9:46 PM.
Thanks ... Jay Novak
313-445-4047
On my 54th year as an SCCA member
with a special thanks to every SCCA worker (NONE OF US WOULD RACE WITHOUT THE WORKERS)
Open source Inverter
.. moved to a new thread ..
Last edited by Neil_Roberts; 01.14.14 at 8:27 PM. Reason: thread creep
#50
See post #50
I haven't built a car with a solid rear axle, but I've designed and built a few with an independent rear suspension, and I'm having a hard time figuring out why it would add $5k to the cost of the car.
Kinematically, both a solid rear axle and a IRS with double wishbones have exactly the same degrees of freedom (two). The difference is that the solid rear axle uses the axle housing as a multiple constraint, reducing the number of links and spherical pivots. Your design still has pushrods, rockers, and springs/dampers (or rubber pucks). Either design can use a single inboard brake caliper (or two outboard ones).
The IRS requires a total of (both sides) 5 more links (2 of them very simple ones) and 4 more spherical pivots than the solid rear axle. It requires uprights rather than simple bearing carriers at the outboard end of the axle tube. And it requires 4 CV joints and two half shafts rather than a one piece drive axle.
The IRS does lose the axle tube and keeps the drive sprocket fixed rather than moving up and down with the suspension.
I calculate the cost differential to be less than $800 at a 10 car set kind of quantity. Add a rear differential rather than a spool and it might be $1500 total cost difference.
What am I missing?
In my opinion, a true entry-level car should train drivers, mechanics, and engineers. For that reason, I would prefer it use the same type of rear suspension as higher-level formula cars, otherwise we are teaching skills that aren't useful as you move up the ladder.
Of course, I have absolutely no idea how to design a good solid rear axle suspension with a spool, so it may simply be fear of the unknown.
Nathan, to do an irs with any kind of a diff or a spool requires a very significant structural extension to the chassis frame along with associated fixtures, required additional labor for fabrication, welding, brackets, spacers, bearing carriers for the diff, adjusters, toe links, upper and lower control arms, cv joints, axles, fasteners. These are the big hitters IMO.
If you are using an open diff you must have 2 brake rotors and 2 calipers and 4 brake pads etc.
I agree that you must still have rockers and pushrods etc for both designs.
As I said, our total manufacturing cost for every component on the rear axle including all control arms and other parts except the rockers and springing medium is under $1500.
Thanks ... Jay Novak
313-445-4047
On my 54th year as an SCCA member
with a special thanks to every SCCA worker (NONE OF US WOULD RACE WITHOUT THE WORKERS)
Jay, I think the big difference I missed was that the frame structure must extend further back to support the wishbones. But how far back? Maybe there's an idea there!
You do have more links (two wishbones and a control link per side) but you already have two links per side and a lateral control arm of some sort for a live rear axle.
If we're counting design and the cost of making fixtures, then it will obviously depend a lot on the number of cars made. But, honestly, if any formula car constructor in the US counted their design and tooling/setup time the resulting return per hour would be a frighteningly small number!
Nathan, The actual total axle location system includes 1 small fabricated A-arm and 4 swagged aluminum tube links. The control arm is a very simple A-arm with 2 rod ends and 1 monoball. The 4 longitudinal links are swagged aluminum tubes that cost about $12 each + rod ends. Thus there are a total of 6 rod ends and 1 monoball for the entire axle location system.Jay, I think the big difference I missed was that the frame structure must extend further back to support the wishbones. But how far back? Maybe there's an idea there!
You do have more links (two wishbones and a control link per side) but you already have two links per side and a lateral control arm of some sort for a live rear axle.
If we're counting design and the cost of making fixtures, then it will obviously depend a lot on the number of cars made. But, honestly, if any formula car constructor in the US counted their design and tooling/setup time the resulting return per hour would be a frighteningly small number!
Thanks ... Jay Novak
313-445-4047
On my 54th year as an SCCA member
with a special thanks to every SCCA worker (NONE OF US WOULD RACE WITHOUT THE WORKERS)
gentlemen
there is a certain element of fun missing in this thread.....take a break and enjoy:
http://jalopnik.com/how-to-build-a-d...sit-1505297936
If a F600 chould be built for 30K less engine and be a full size car like a F1000 without wings with real shocks (say a spec shock that is cheap like the circle car guys no mods to shocks), formula car body with a rear diff. Basicly same as FF and FC used to be 1 with wings and one without. Make the car have no electric shifter, keep it a traditional shifter don't even allow push pull paddles and I think we would have a winner.
I'm not saying it's possible but if that was a option I would sign up.
Mark Filip
I have had a formula car builder tell me that the only reason that he is not building F5/6's is the rubber puck. If any of these above suggestions are allowed it will only increase the cost of the car. All of this was debated back in 1983 when F440 was being proposed for national class. We went around and around comparing the cost of each component discussed in this thread and finally decided to keep it simple to keep the costs down and this approach has worked since 1984. The only changes, outside of engines, have been: (1) the lengthening of the wheelbase from 72" to 80" for foot safety and high speed corner stability, (2) club mandated bigger diameter tubing and (3) adding a diffuser for high speed stability. The last change to add the optional motorcycle drivetrain is to increase participation. This will take time so be patient and you will see the growth.
Jim
Been messing with these cars since 1982
We proposed very nearly what you are asking for & the Club turned it down. NO MORE NEW CLASSES! They told us to fit within F500 or go away. So we made the rules to fit within F500.
Now that said it would be very difficult to build and sell the car you want for $30K. It is all about the quantities. if a builder could do 100 cars then it would be possible. No way at lower quantities.
Thanks ... Jay Novak
313-445-4047
On my 54th year as an SCCA member
with a special thanks to every SCCA worker (NONE OF US WOULD RACE WITHOUT THE WORKERS)
The most recent Sportscar had a looking back on the second to last page with the numbers for SRF when it started. I think they said there were around 150 orders!
I understand what happened Jay I'm just saying that in my mind would have be ideal. It's a shame SCCA has 4 million classes and 75% have very few cars.
Mark Filip
the price point is $25k... (roughly one-half of the US median household income end of 2011)
why not claimer races.......run what ya brung (bought or built) just be willing to turn it over?
no new class or cars required but maybe a new race group
Tried claimer rule in F440 back in the 1980's - never actually carried out by anyone for
about 8 years so it was dropped.
Jim
Says the guys who drives in a breakaway class...
Seriously, let it go. This argument has been going on since people wanted a Ford Model A in a color other than black.
Stan Clayton
Stohr Cars
entry level
Hello Gents,
I think I'm the guy SCCA is looking for. I'm a Dad with a 14 year old kart driver who has had some success. We don't want to stay in karts forever. He's 15 next summer and can get his SCCA competition license. I'm an aerospece engineering with disposable income and a closet racer. Been doing track days for 8 years. I work with and know lots and lots of young engineers (24-30 years old making 60-75K/yr) that are crazy car guys with good incomes. We want to RACE! The internet gives us access to all these sites. SCCA is full of lots of old guys (no offense, I'm 62). We live in Florida - Sebring, Daytone, PBIR, Homestead, Roebling, Road Atlanta, Barber, NOLA.
Where do we go from here? He loves open wheel. FV, FF, F500? I know about costs. Ever been to kart races with the factory semi-trailers and factory teams? As with ALL racing, dollars mean winning. But we want to do something for life, love of the track, competition, and community. I don't have a business that I can write off costs off as sponsership. I don't have a big shop, I have a two-car garage. But he's a good driver and I can turn a wrench. Usually top 3 finishes against national level competition (go look at Ocala Gran Prix race team). Not bad for a couple year-old used chassis and used engine.
OK, got the picture? What do we do? FV with an outdated chassis and engine. No problem. Small field at Sebring last month, 6 entries. F500? 4 entries. FF is better, grid of 12. I see some of the young guys posting here with dreams of racing, and small budgets. I read lots of posts on affordable entry classes. Many get pooh-poohed about how expensive. Purchase, tow vehicles, travel, tires, etc.,etc.
Does SCCA want to attract new younger racers or not? Read lots of posts of how the fields are getting smaller and smaller. See lots and lots of guys at the tracks with 60K tow vehicles, 35K trailers, 30K race cars. I don't begrudge them. If I had the $$$'s I'd do it too, but I don't and there're lots of us race crazy guys that don't. I know, I'm with them every month at the kart tracks, racing.
Give us something to race with. We know Ferrari isn't going to call next week (don't tell the kids). SCCA has lots of closed wheel classes, but most all of the kids love open-wheel racing. Formula what-ever, don't care as long as we can do 6-7 races a years.
With all respect to the years you guys have put in to build what is a really good foundation, make an entry level class that will fire these kids up.
eshane..................
spoil your kid..............send him to Skip Barber at NOLA............i think they were just offering the full 3 day course for south of $3k
then .............................
The SCCA Board of Directors did just what you are asking for - Formula 600 is now an alternative drivetrain in the F500 class. They made that declaration in the Fall of 2011.
It is in their minutes: "We want a budget entry level motorcycle formula car class."
Jim
Been messing with these cars since 1982.
Well Said
Absolutely agree. That would be my choice for my kid. You can also fit the car, spares, etc in an 18 foot trailer. Easy to set up, a lot of "self-containment" in the engine/gearbox department, lots of speed and something familiar. I think F-600 is the best up-and-coming class for open wheeled racing.
Best, Tom
Tom Owen
Owner - Browns Lane and Racelaminates.com
Here is my suggestion. And this is from a guy who raised 5 kids and they are all off the payroll now and none race.
You need to be on the track, not on the side lines dreaming about what could be.
I would recommend you start in FF and start with what you can afford. A lot of your investment will be in the class and carry over to whatever car you run.
Next really get your car ready and that probably means rebuild what you buy.
I would look for cars that have shown well over the last decade; Swift, VD, Citations, etc. Many of these cars were built in the 90's or earlier. But when well prepared, with good tires and engine, and well driven, almost any of these cars can be winners.
The first upgrade I would recommend would be a Honda engine. This engine will last many years and can be moved from chassis to chassis.
I would spend your first year racing local and as often as you can. When you get comfortable and get some speed, try a few F1600 pro races at tracks you know. I would plan to run the pro series for a season with less than top equipment. Spend you money on engines and going racing. You are perfecting your preparation, setups and driving skills. By the third season you can look at upgrading your car and look to winning races and championships.
Finally master the class you are in before going to the next class.
12 cars to race against in FF ain't bad - there's probably one running at about your pace whatever that may be. I'd still start with an obsolete CF, learn how to prepare it and race it well enough to run mid-pack, and only then sell the CF for what you paid and think about spending the big bucks or moving on to faster cars and an aero learning curve. We had a teenager here who went from a year with us in EFF (any-age FFs on DOT tires) to the Pacific pro series for a year and got a couple podiums in Britain last year.
And the Skippy splurge is a great way to sink the hook.
Last edited by TimH; 02.10.14 at 9:31 AM.
Caldwell D9B - Sold
Crossle' 30/32/45 Mongrel - Sold
RF94 Monoshock - here goes nothin'
I'll second the notion of a Skip Barber 3-day course with one small caveat:
The 3 day course has a curriculum designed for drivers who've never driven a race car at all and so the first part of the course will definitely be a little slow-moving for someone who's spent a good bit of time racing karts.
There's good stuff to learn about vehicle dynamics... ...but your son will almost certainly be a little antsy by the time they actually get him into a car. Heck, I'd never turned a wheel on a track before I got there, and I was getting impatient (because I'd been preparing to drive a race car on track for almost my entire life).
Yes, but not by adding any additional classes and for the most part the old timers aren't willing to support any rules that will make their current class more attractive to others at their own expense.
My advice; stay in karts as long as he finds it fun as the level of competition will never be the same. Even at the RunOffs it is the exception to have 3rd place finish within 10 seconds of the winner. It is rare to have the TOP 3 qualify within a couple of tenths.
The two of you would have to decide what it is that you expect to get from car racing that you weren't getting from karts.
If Wishes were Horses
"You need to be on the track, not on the side lines dreaming about what could be."
Now from an "Old Guy" who has raced a couple of times.
The Parameters:
The tub/chassis would be separate from the rest:
a) Has the FIA intrusion specs met. Don't really care if it is a tube frame with intrusion panels or composite tub. This is coming as a requirement so get ready for it. The cost can be controlled by using modern manufacturing methods (3D printed bulkheads or CNC for instance). Same for uprights, make them common. The rest of the stuff is either tubing or simple sheet metal less the attenuators and those could be a "spec" (and I really hate that word) single sourced item with interface adapters.
b) The roll bar is a "bolt on" with different heights available. Making the market more universal by allowing even my fat a$$ to fit without having to redo the chassis.
c) The engine bay structure is a "bolt on" allowing different engine/transaxle combinations without having to redesign or replace the car. Suspension geometry can stay the same.
d) Allow "Paddle" shifting/sequential gearbox. With the newer allowed engines requiring an alternator the power source is there. This doesn't mean that you would have to throw away what you have. Even a Hewland Mk9 can be upgraded to a five speed.
e) Inboard spring/shocks are a must. There is no reason to have to replace expensive shock units because of an "incident" just don't allow the $1000 shocks in the lower classes. ($600 claimer would stop that real fast)
The idea being to be able to upgrade FF/FC/FB or even FV and their clones without having to replace everything in the garage. AND allowing those so inclined to mechanically "play" with their car. Having been thru the tire-trick car of the week period all it did was increase cost and move me further down the grid. And that ain't no fun.
Tuck
I suspect I'm one of the types of people that the future of formula/sports racing will want/need. So here's my take from someone on the outside looking in.
I'm a 27 year old engineer, decent pay check. I like the design/analysis/testing aspect of the sport as much as the actual driving. A combination of following F1/LMS and just wanting to go kinda fast on track with a safe ride got me here. I have no intentions of racing for anyone, and I know my checkbook will be paying for every moment of track time. For now it's autocross and maybe some karting in the short term. F600 in a couple years I suspect. Might move up a class, but I'll never race FA cars (unless I hit megabucks) I've spent the past couple of weeks thinking about what I would want from a class.
As to budget, car cost isn't the driving factor. Yeah, a $35 or $40,000 car would take budget changes and probably a few years of saving (and they become $15-25k cars in a couple years used). However, it's the $3-6k race weekends that turn me off. Two sets of thousand dollar tires for a weekend is a deal breaker. $9000/year engines are a deal breaker. $600 for pads/rotors/fluids is a deal breaker. Address that and I can work out the rest. Sure those costs say kart, but as someone pointed out, they're karts, not cars. Maybe it's stupid and trendy, but if I'm going to spend time and money, I want a real car.
So what would I do? Spec a non-slick tire, good DOT-R's or similar, something I can get two $1000 sets through a season. Require the engine to be a stock engine either a 600 motorcycle, 1000cc motorcycle or maybe a modern 2L I4. Something stock that will get through a season or two. Sorry, I don't want a carb'd car. Only things I've driven with carbs involve mowing lawns. No interest in learning as I'd rather learn to tune an ECU. Suspension controls are okay, but I can live with suspensions that cost a 1/4 of the guy with the Motorhome's setup, I'll just have to drive better. I'll probably live with rubber pucks, but I'd rather not. +1 to inboard so they don't become consumables. If it's necessary to spec other components, look at the circle track or street car stuff where possible so it's available at a reasonable price.
Personally, I'd go fairly open rules beyond there. I decidedly don't want a spec series, allow me to be creative, and drive against a variety of ideas. Some aero would be nice, but I can take it or leave it. I'm less concerned with materials used. CF isn't magic, and weight limits can be the ultimate control. I'd design a class that allows for homebuilt or purchased chassis. I could be wrong but I suspect there's a fair portion of my generation that would be big on designing their own car. The Make scene and Arduino stuff tends to suggest that. But then provide a good (web) place for builders to work together, trade parts, and ideas. Then promote all of the above.
Give me an 800 or 900 pound car so that I can toss it on an open trailer and pull it with my daily driver and will only take up a bay of a garage. If someone wants to beat me with their checkbook I can live with it, I'll be having fun, and it'll drive me to drive better.
Probably not entirely coherent, and some of it may even conflict, but that's my thought. Hell I kinda want to build one of these and race FS.
What you are describing is very close to an F600.
I agree, which is why I'll likely end up there, but a more open set of rules wouldn't be hurt. There's certainly room for flex in the rules to allow for interesting solutions without huge increases in budget. Unfortunately the restrictions make it somewhat less interesting for someone who thinks the engineering side of things is an important part of motorsports.
Also, before I ended up sidetracked on specs my general point was controlling ongoing costs is more important than a nickel and fined chassis.
hey spaceman
"Probably not entirely coherent, and some of it may even conflict, but that's my thought. Hell I kinda want to build one of these and race FS. "
there ya go....................sounds like FS is your deal!
Experience tells us that the more open the rules are, the higher the costs go. That "engineering" you mention is big sinkhole for cash....trust me. The F600 ruleset has been debated and fine-tuned over years and years, with a strong focus being cost control.
Marshall Mauney
Milwaukee Region
Respectfully, I must disagree a bit.
I find the costs are much more a result of the level of competitiveness desired than the ruleset. Sometimes open rules give you options to pursue less expensive alternatives, sometimes spec or tightly controlled parts get stupid expensive for what they are.
It's all a matter of just how far your competition has raised the bar.
i agree with Daryl
"I find the costs are much more a result of the level of competitiveness desired than the ruleset. Sometimes open rules give you options to pursue less expensive alternatives, sometimes spec or tightly controlled parts get stupid expensive for what they are. "
especially with a class such as FS i think
In 1984 you had the option of buying a DB1 or Sports Renault. I think that if you look at the cost of racing those same cars every since say 1984, you will find the FF DB1 was way better buy than the SR. Also the resale value for the DB1 is close or slightly above the initial cost.
I think that a well though out set of rules can produce a class that is both competitive and at a reasonable cost level. That is especially true with the engines that are available today.
My thought is a class of cars built from standardized components, much like FV. Components that are built to a single design but no restriction on who produces those parts. The only thing spec about the class would be drawings for the standardized components. Over time I think that various manufacturers would step up and produce components at very competitive prices.
You have described Formula Ford on DOT tires. An $800 set of tires lasts a season. Brake parts are cheap, I4 1.6L engine is cheap, $4500 engine will get you through a couple of seasons, etc
who runs that and where?
And a 600cc Suzuki GSXR delivered with everything you need from the bike is $850. Almost everything else in F6/F5 is cheaper than a FF. F5 was designed in 1984 to be much cheaper than a FF and now they go about as fast as a FF AND have sidepods for better packaging and better protection from side impact.
Jim
Been messing with F4/5/6's since 1982.
OK, let's put a few things in perspective. I'll use my current FE as an example; FE is in the same basic speed range as FC, but is a spec class. Generally speaking, spec is a good way to control costs, as you don't have to chase the fastest-part-this-week in order to stay competitive.
Car cost - $30-35K for a reasonably good existing car. New ones are higher, but you can generally find a car to buy when you're ready. In spec classes, the price when you sell won't be radically different then when you bought (assuming you maintain it in the same condition).
$3-6K weekend is high, from my experience. YMMV, but you can control a lot of this by doing the work yourself, using family/friends as crew, keeping the car on track and not trying to occupy the same space as another car, etc.However, it's the $3-6k race weekends that turn me off.
More like $800 for a set of tires in FE. FE rules force us to race on the tires we qualify on, and we generally use our race tires for practice the next weekend. It's possible to run a set for two single-race weekends if you want to stretch the budget. You could run new tires for practice, but that's spending more than necessary, IMO. Different classes have different rules, so don't assume you know the tire costs for a given car until you've talked with a few competitors.Two sets of thousand dollar tires for a weekend is a deal breaker.
FE engines run years and years. I've heard 30+ races, and the only one I've replaced in 6 years was the one I burned up by running it too lean.$9000/year engines are a deal breaker.
Rotors will always be expensive in pure race cars. That said, different cars wear them at different rates. I ran the same set of rotors in F500 for several years; changing pads seemingly constantly, but never wore down the rotors. FE consumes rotors faster, but still you're talking about a front set every couple of years, not every weekend (and the FE has monstrous braking).$600 for pads/rotors/fluids is a deal breaker.
Brake pads are a consumable in any racing application. Smaller pads are cheaper, but get replaced more often. In the end, it's basic physics; the only way to change the amount of pad material you consume is the change the weight of the car or limit the braking potential (i.e., give up braking force and go slower).
You don't need to go non-slick - in fact, a hard-compound slick will wear better and last longer than a DOT tire. Look at the Club Ford rules across the country - several areas spec a hard slick that can be run for a full season (American Racer, GY 600 compound, etc).So what would I do? Spec a non-slick tire, good DOT-R's or similar, something I can get two $1000 sets through a season.
Better yet, pick a class without ECU tuning. The motorcycle-based classes seem to go through engines pretty rapidly. Less expensive when it blows, but you're still losing a lot of track time as a result. The FF (Fit), FE, FM and Spec Racer Ford get great reliability and longevity out of stock-based 4-cylinder automotive engines. Reliability is generally achieved by not allowing the racers to tune the engine to within a hair of it's life - sealed, matched engines almost always run longest.Require the engine to be a stock engine either a 600 motorcycle, 1000cc motorcycle or maybe a modern 2L I4. Something stock that will get through a season or two. Sorry, I don't want a carb'd car. [...] No interest in learning as I'd rather learn to tune an ECU.
Suspension costs are real, but they are basically a one-time expense. Yes, you may need to rebuild shocks once every few years, but that's not a major portion of your total costs. Whatever car you buy will come with a suspension; build a full shock rebuild into your initial prep plan and you'll be fine.Suspension controls are okay, but I can live with suspensions that cost a 1/4 of the guy with the Motorhome's setup, I'll just have to drive better. I'll probably live with rubber pucks, but I'd rather not.
Pucks are certainly less expensive though - they are just in another world from a tuning standpoint.
One thing to keep in mind is that open classes will allow/require you to test with and select different spring rates front and rear, while a spec class will hold you to a single option, thus again reducing cost and complexity. You may not like the spec spring rates you have to run, but it won't put you at a disadvantage to everyone else.
You've left out a BIG piece of the puzzle - the transmission. How many tracks will you run at, and does your car/class/series allow ratio changes? I tend to think of individual gear pairs as $3-500 per set. A 5-speed with gearing for 5 different tracks gets to be a lot of money. Again, a spec transmission with fixed ratios makes a big difference in $$$; the alternative of running a stock bike engine/transmission set also limits this cost potential.If it's necessary to spec other components, look at the circle track or street car stuff where possible so it's available at a reasonable price.
Keep in mind that 99.9% of the time "creative" = "expensive". Fun, but expensive.Personally, I'd go fairly open rules beyond there. I decidedly don't want a spec series, allow me to be creative, and drive against a variety of ideas.
The closest thing to what you are describing is F500/600. The guys leading that class have been rabidly focused on keeping it low-cost while retaining the ability to "run what ya brung", and it's worked pretty well.Give me an 800 or 900 pound car so that I can toss it on an open trailer and pull it with my daily driver and will only take up a bay of a garage.
I'd point out, though, that having such a light weight limit is going to push the use of exotic materials. If your goal is to keep it cheap, you need to go heavy enough that an inexpensive design with a 200-lb driver can hit the minimum. Otherwise, you will start to see either high-$$$ materials like CF or you will see parts that are lightened to the point that they become unreliable. TANSTAAFL.
You'd be alone at most races in FS. It's the right place for pure creativity, but it's also the right place for old Indy Lights cars, Ferrari engines stuffed into an old FA chassis, etc. Bring bags of money if you want to be in FS.Hell I kinda want to build one of these and race FS.
Last edited by Marshall Mauney; 06.16.14 at 7:01 PM.
Marshall Mauney
Milwaukee Region
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