Entry Level Formula Car

[nulrich]

I'd love to see an entry-level electric formula car, but the technology isn't there yet to make it economical.

A 60 hp electric motor at 80% efficiency for motor and controller running about 75% full throttle would require a 21 kW-hr battery pack for a 30 minute race. That's between 2000 and 3500 of the 18650 lithium cells used in laptops (and in the Tesla). It would weigh about 250 lbs for a mid-range cell and cost on the order of $10k in the kind of quantities a race car represents. You could make it cheaper by using lower capacity cells and vice versa. (The battery type used in the Zero S would weigh about 320 lbs for a race car and cost about $15k.)

Then you would need a water-cooled motor and controller running at at least 300 V. Safety aspects aside, that system alone will be a lot more expensive than a 600 cc motorcycle drivetrain.

Charge time would be 15 hours from a 120 V normal outlet (1500 W charger).

And that ignores all the engineering and development time.

We ain't there yet.

Nathan

P.S. Motorcycles are a whole different animal, the numbers work much more favorably there.

[JBlock]

Time to stop lurking and add another $0.02 Great thread, been following it for days! Thanks to Steve for getting the ball rolling and all the ideas and multi generational perspectives and even the tangents are interesting. This is the type of activity that is necessary our sport alive.

Okay now the two cents. Perhaps a new class is in order, I have often thought about it myself. Would it attract more new participants, or get past folks to return? I don't know.

So is the root of this whole thread, that cost is an issue we need to address? Or is it that we need to attract more folks with the hope of one day seeing car counts like the 70s & 80s? Or is that eventually, the bones for FV will be depleted and a reasonable replacement is in order? Or finally, is that we are all just a bunch of speed freaks and we need some way of getting our fix?

Regardless of sanctioning auspices, this is (IMHO) the exact type of discussion we need to be having. But, perhaps we need to revisit whatever that socioeconomic/culture/common skill & knowledge factors, model was that sparked the boom of the 70s.

[Jnovak]

Jay, what would be wheelbase have to be to accomplish that for a 6'5" driver and a 600 cc motorcycle drivetrain?

Nathan, we built an F500 for Don Hamilton who is 6' 5 1/2" tall in an 80" wheelbase car. Is was amazing to see him get in and out of the car. Actually we could easily do a 90" wheelbase car that would fit you very nicely. In fact our proposal for a stand alone F600 class was for a max wb of 90" and a max width of 60". No problem for you to fit in a car like that.

I agree with your other comment about the 600cc MC engine being a great low cost powertrain for an entry level class.

[veefan]

Nathan. "electric" entry level?

This is amazing, High school kids can figure it out at a very low cost and we're talking about $20K entry level cars. Pathetic

We aren't "there yet" cauz we're a bunch of grumpy old men (most of us), who all have our perspectives set in stone to what "entry level" means. My HIGH school son participated in his High School Electrathon team. THEY FIGURED IT OUT.

http://www.theridgefieldpress.com/41...-electric-car/

The "Formula" is already figured out...
http://en.wikipedia.org/wiki/Electrathon


High school kids built this from scratch for a tenth of the cost of a formula vee! My son was part of the built team and he drove the car at Limerock with my helmet with all the pretty SCCA annual tech stickers.




PS in his class 50!!! teams participated! all local!

[Jnovak]

The discussion about independent rear suspension focused on the cost of the rear drive assembly.

A spool would be the least expensive. I have drawn something that I could stick in a Citation FB. The aluminum material from McMaster-Carr is $83 for the 2 pieces. One is flat 6"x6"x 1.5" and the other is 4" diameter 6" long. There are 2 VW CV joints at $40 each. and 2 bearings 90mm ID, 140 mm OD and 24 mm wide, double sealed at $120 each. 2 CV joint boots (which I don't have a price for), 6 5/16x24 by 8" long bolts at $2.54 each and 6 K nuts at $0.84 each. That is $423.28 in materials less the boots. $300 machining time and you have drive assembly for well under $1000.

Given time I might be able to come up with a differential and still keep the assembly under $1000.

Our new F600 COMPLETE rear axle assembly including all control arms, rod ends, bearing carriers, bearings, wheel hubs, sprocket and rotor carrier and chromoly axle is under $1500 our costs.

Any IRS with all the added frame support structure, uprights, control arms, axles, cv joints etc will cost a minimum of $5000 added cost to a car compared to a chain drive live axle.

Here is a picture of an axle assembly on a chassis. The brake caliper is not included in the cost above. Labor to assemble the axle is 2 hours for the complete assembly.

[Parker]

Can you please post a side view of that control arm setup!?

I'm dying to know how you get vertical force applied to the chassis from what looks like a horizontal push/pull rod.

[Jnovak]

Can you please post a side view of that control arm setup!?

I'm dying to know how you get vertical force applied to the chassis from what looks like a horizontal push/pull rod.

You learn a lot designing elastomer springing suspension systems. However, it just looks that way from that view, the pushrod is not at all horizontal. The shock motion ratio is .95

[Daryl DeArman]

http://www.apexspeed.com/forums/show...t=57027&page=3

POST 88, slide 2

[S Lathrop]

Going back to Stan's graph in post #139, you see that F500 only once has had the participation level of FV. That is comparing the best ever for F500 and the worst ever for FV.

Relatively speaking F500 is holding up way better than any other class. But F500 is declining as are all other classes.

F500 gives the best performance (speed and lap times) for the dollar of any class but the numbers have never been very high. Why is that?

FB has had reasonable growth over a few years for a car that is way more expensive than F500 and way more demanding to drive. Is this an indicator?

If we could produce FB like cars, with FV /F500 performance for prices close to F500/F600 could we see a class that would grow to FV/FF levels or would we just be adding another class to clog up the track and divide an every dwindling entry among more classes?

An implied question in this thread was "will the right product bring new participants to road racing?". Just moving guys among the classes we have is a pointless exercise.

This is a long way of saying that I don't see that using the F500 as the starting point for a new entry level class is the way to go. The F600 is probably just right as it is and as it will evolve. I was hoping that there was a better approach.

[jim murphy]

Going back to Stan's graph in post #139, you see that F500 only once has had the participation level of FV. That is comparing the best ever for F500 and the worst ever for FV.

Relatively speaking F500 is holding up way better than any other class. But F500 is declining as are all other classes.

F500 gives the best performance (speed and lap times) for the dollar of any class but the numbers have never been very high. Why is that?

FB has had reasonable growth over a few years for a car that is way more expensive than F500 and way more demanding to drive. Is this an indicator?

If we could produce FB like cars, with FV /F500 performance for prices close to F500/F600 could we see a class that would grow to FV/FF levels or would we just be adding another class to clog up the track and divide an every dwindling entry among more classes?

An implied question in this thread was "will the right product bring new participants to road racing?". Just moving guys among the classes we have is a pointless exercise.

This is a long way of saying that I don't see that using the F500 as the starting point for a new entry level class is the way to go. The F600 is probably just right as it is and as it will evolve. I was hoping that there was a better approach.

What Phil Creighton told me during last Fall's meeting about what to do with F600 was that even though F500 race entries were fairly steady over five years the number of F500 DRIVERS was declining over this same time period. Per Phil, this one factor swung the vote over to allowing F600 to merge with F500 class.

Why low F500 numbers? Ever since I started running F440/F500 out of Atlanta in 1982 the people would come up to my paddock and look at the cars and say this: "I love the low cost of this class BUT (pick one) I don't like two strokes and/or I don't want to learn how to tune the CVT clutches and/or I want to shift gears and/or there are no snowmobile dealers down here in the south and/or some other reason". They would also say: "I am familiar with motorcycles, why don't you run them, instead?" This went on for years. We perservered until about 2009 when we ran into a wall that just knocked us on our butts. The snowmobile drivetrain is designed for cold weather meaning that as the air density changed during a day at the track we were almost continuously changing carb jets, even in the grid. If the two stroke was not at its optimum fuel/air ratio it would just lose enough power to affect the tune of the CVT clutches thus the result was slower lap times and lost races. The races became not who was the best driver but who was the best tuner. These tended to be northern drivers who had local snowmobile racers to help them. When people saw what we were doing just to be competitive they shook their heads and walked away and chose another class. We tried to introduce EFI on these motors to help with the tuning but were rebuffed primarily by the northern drivers. When we saw the lost cost of a 600cc MC DRIVETRAIN when compared to just a new Rotax MOTOR with nothing on it, we converted our KBS Mk.5 to a Honda 600 in 2009. When others saw our cost figures, heard the exhaust sound, saw the sequential paddle shifter, and had the familarity with MC's in general the class has grown, just as a regional class only, to what you see today. This is what happened to F500 and how F600 started.
The more that you go away from simplicity the more it costs.

Jim

[S Lathrop]

Jim;

If you are right that the advent of the F600 variant of F440 has solved the problems of the class, then you should see a good growth over the next several years. Then the FB guys should see new recruits to their ranks from F600 when some of those guys want to go even faster because they are already tuned into MC powered race cars.

[Jnovak]

I also think that F600 has some serious potential for growth. I think that 4 or 5 years of growth will create a great higher tech entry level class that will bring racers to the club.

[jim murphy]

Jim;

If you are right that the advent of the F600 variant of F440 has solved the problems of the class, then you should see a good growth over the next several years. Then the FB guys should see new recruits to their ranks from F600 when some of those guys want to go even faster because they are already tuned into MC powered race cars.

That is indeed our hope. We are getting more inquiries than we ever did while we were two stroke. Everywhere we race now the reaction is just the opposite of the old days.
We feel strong enough about the class that we are now renting F600's -
www.formula600racing.com .

And go here for our pro series that is marketing our class -

www.theformula600challenge.com

Front page has our history via press releases - worth reading.
The website is still under development.

Jim

[formulasuper]

I've said it before; 15 yrs late.

[Stan Clayton]

I've said it before; 15 yrs late.

You're going to have to elaborate on "it", Scott.

[R. Pare]

Probably referring to the switch to 4-stroke engines. I'm among those who HATE the sound of a 2-stroke, and if I were a young driver looking for a class to run in, anything with a 2-stoke would be immediately dismissed as an option.

[formulasuper]

You're going to have to elaborate on "it", Scott.

Stan, as some in the class may remember, back in 96-97 some of us F440/500 racers that didn't like the CVT/2 stroke constant tuning problems wanted to switch to the "then new" sport bike engines but the club was having nothing to do with it. That's when I & others moved on or out. Good to see it's finally being proven to be the correct idea.

[Stan Clayton]

Thanks Scott. I wasn't paying any attention to F440 back then, so wasn't aware of the controversy.

[provamo]

#205............that looks cute.........really

[jim murphy]

Stan, as some in the class may remember, back in 96-97 some of us F440/500 racers that didn't like the CVT/2 stroke constant tuning problems wanted to switch to the "then new" sport bike engines but the club was having nothing to do with it. That's when I & others moved on or out. Good to see it's finally being proven to be the correct idea.

I remember that it was the northern drivers who were adament against any change.
We had better numbers back then but it has been declining ever since.

Jim

[Steve Demeter]

Probably referring to the switch to 4-stroke engines. I'm among those who HATE the sound of a 2-stroke, and if I were a young driver looking for a class to run in, anything with a 2-stoke would be immediately dismissed as an option.

F 600 cars sound like mini F1 cars. Really great sound.

[jim murphy]

F 600 cars sound like mini F1 cars. Really great sound.

And this is just one of the reasons that we think that F600 (or F500MC?) will grow.

Jim

[Amon]

Jim,

Excuse my ignorance, but what type of rear suspension are you using with the F600?

Thanks!

Mark

88' Citation 002'

[S Lathrop]

The last car that I worked on that had a solid rear axel is in the Speedway museum. It was a USAC dirt champ car.

Looks like I might have to learn something about solid rear axels and not just spools.

I was looking for some old drawings and came across a drawing for Ed Zink's F440.

[ChristopherBernard]

Congrats, Jay on a nice job with the F600 rear suspension.
Steve, check out the solid axle on my DSR effort from some time ago,the Kokopelli.
Solid axels can be used to good effect. Very stable roll centers.

Chris Bernard

[Jnovak]

Live axles do not have to be crude. They can be very sophisticated and they actually have some advantages over an IRS. I will leave it to you to figure it out.

[Purple Frog]

Hard to get camber for radial tires.

[Jnovak]

Hard to get camber for radial tires.

I agree with that sir Frog. However there are plenty of bias ply tires available that can do over 2 G's in our cars and I have data that shows that.

Our F500 that Brian won the Runoffs with in 2007 STILL, to this day, holds the F500 lap records at both courses at Mid-Ohio and at Grattan. His records are also STILL faster than the FF records on both courses at Mid-Ohio and at Grattan and both of those tracks are handling courses.

[provamo]

Hard to get camber for radial tires.

it has been done...........NASKAR

[Jnovak]

Actually our tire data shows that we have between 10 deg F and 15 deg F negative camber in the rear tires. This is very decent.

[S Lathrop]

Jay:

Your new car looks like it has the potential for significant down force.

Have you tried to measure how much it makes?

[jim murphy]

The last car that I worked on that had a solid rear axel is in the Speedway museum. It was a USAC dirt champ car.

Looks like I might have to learn something about solid rear axels and not just spools.

I was looking for some old drawings and came across a drawing for Ed Zink's F440.

IIRC, Mike Leathers drove a Zink F440 to one or more Runoffs Championships in the 1980's. It was a VERY simple design due to the claiming rule back then. Mike Leathers, David Elliott and Rusty Cook spent some time with us at the ARRC at Road Atlanta last November.

Jim

[Stan Clayton]

it has been done...........NASKAR

NASCAR doesn't use tubular axles. To gain rear camber and toe-in when we raced circle track we would lift the rear so the weight was off the tires. Then, using two cutting torches set to a soft flame, heat a round patch of the top of the outboard end of the axle housing until it was bright red. When the heat was removed the housing would contract a bit as it cooled. Measure and repeat as needed to get the desired camber. Repeat for toe-in. There is enough compliance in the axle shaft and bearings to accept a half a degree or so without complications.

Can't do that when the tube IS the axle...

[jim murphy]

NASCAR doesn't use tubular axles. To gain rear camber and toe-in when we raced circle track we would lift the rear so the weight was off the tires. Then, using two cutting torches set to a soft flame, heat a round patch of the top of the outboard end of the axle housing until it was bright red. When the heat was removed the housing would contract a bit as it cooled. Measure and repeat as needed to get the desired camber. Repeat for toe-in. There is enough compliance in the axle shaft and bearings to accept a half a degree or so without complications.

Can't do that when the tube IS the axle...

You can now buy a complete rear axle assembly with several degrees camber and one degree toe-in from Speedway Motors (Lincoln, NE). The male and female splines are now curved for the mis-alignment. My autox E Mod yellow Jeep has a Ford 8" this way from Speedway.

Jim

[S Lathrop]

IIRC, Mike Leathers drove a Zink F440 to one or more Runoffs Championships in the 1980's. It was a VERY simple design due to the claiming rule back then. Mike Leathers, David Elliott and Rusty Cook spent some time with us at the ARRC at Road Atlanta last November.

Jim

I did not follow Ed's success with the F440. I just knew he did one and he gave me a copy of the promotional drawing. I do know that he pioneered the pull rod (or push rod) front suspension and using the rubber bumpers as a suspension medium. Prior to that all the cars were go cart derivatives.

The last car I did for ED was a DSR powered by a Yamaha TZ750 bike engine. We also explored a S2000 project about that time but never built the car.

[Stan Clayton]

You can now buy a complete rear axle assembly with several degrees camber and one degree toe-in from Speedway Motors (Lincoln, NE). The male and female splines are now curved for the mis-alignment. My autox E Mod yellow Jeep has a Ford 8" this way from Speedway.

Jim

You could then, too, Jim, but most local racers simply made their own from instructions in the racing magazines of the day.

[S Lathrop]

I still think that there might be an "appeal" issue with the F500/F600 package. But given that there have been so many changes in the package, it will be interesting to see if F600 will be the new standard for an entry level formula car class.

I would prefer a class that would be closer to FF. Tires could be either current FV rubber of FF fronts, small tires for the front and larger fronts tires (FC) for the rear. A 600 cc bike engines restricted to something in the 75hp. to 100 hp. range. And 800 to 900 minimum weight, post race with driver. Something that could make use of the frames and body work of FF but with lower cost suspension components.

I think that the cost of the rear drive assembly is one of the biggest cost issues to be worked on. My thought is to see if the differential from some small car along with the output flanges/drive joints can be adapted to a chain drive setup similar to what F1000 uses.

But if F600 takes off, we already have the class and this was just a fun winter mental exercise. Otherwise maybe we should take a new look in a year or two.

[John]

I think something could be done to make an inexpensive open diff for the back end. That might help, also if you specify a shock and brakes (wilwoods or the like) for the car, there has to be something in a coil over that would work or could be valved to work you have a good start.

The think I like is a new race could start with a 600, and then add to the chassis and move up classes to FB if they wanted, and the builders can leverage common infrastructure.

[2BWise]

This has been a fun thread to read thru even if it is just a mental exercise. I'll throw my thoughts into the ring too.

The idea of common parts is a huge factor in all of this. Standardizing the big expenses of a racing car do a lot to drive the costs down. The issue becomes that you start driving the formula into a spec realm, which I think a lot of people in this thread have an aversion to. I do as well.

What if the following parts were all standardized:
-Chassis, forward of the roll hoop (monocoque would remove bodywork expenses) is standard. All the suspension pickup points are standard, with standard location to mount items like a steering rack, wheel, pedals, shifter.
-A standard engine or range of engines (600 or such) with standard intake and ECU.
-Standard rear box and diff assembly
-Standard upright and hub assembly
-Standard cooling package and oiling package
-Shocks and springs open, but limited to single adjustment for rebound/bump
-13" wheels at a standard width and square tires
-And generally, dimensions for the vehicle fit within current FF/FC restrictions (Wb, track, overall length, etc.)

My idea is to bulk build all the big expenses in building a race car, but leave lots of little things open for the designers and tinkers to play with. With standard chassis mounting points and a standard upright it's up to the builder to design the a-arms and damper actuation. The rear subframe containing the engine is open, so engine position can move and vary as well as overall length and weight distribution. Shifter actuation (mechanical only) is open. Braking is open, but is obviously limited by packaging space.

The race car builders could supply kits that add all the missing pieces from the standard kit, or if someone wants to home build all the pieces he could buy the standard kit and design/build the rest. It would be an open development class but certain restrictions would inherently be put in place by the usage of the same standard kit for the big items. With standard suspension pickup points there is only so much one can do with kinematics. Think of it as buying a "Citation" kit with just the chassis, uprights, bellhousing. Buying the transaxle/engine. Then the rest is up to you.

Its the high school science experiment where you drop an egg from the second floor window without letting it crack. This time all you get to use is a cardboard box, a Styrofoam cup, a rubber band, a length of string, and an egg.

[nulrich]

Differentials are cheap. Here's an available LSD diff assembly set up for chain drive for 629 GBP ($1000) that's made to order. If designed for production and made in quantity it could be done for well under $500, maybe less. I've sourced an unhoused open differential at this kind of power level for under $100 from China (quantity 50).

http://www.chaindrivediff.com/

There are fewer parts with a solid rear axle, but I'm not sure the cost differential (excuse the pun) is really that high. That said, F600 is an established class and it will be interesting to watch it grow over the next few years.