FormulaGRM

Okay, here's the mission. Ala FSAE your job is to conceive a track day car (not a cone-chaser). The task is to designate a layout (e.g. front engine/rear drive or mid-engine) tube frame open wheel race car. You must specify the components with the least cost, most availability and best reliability necessary to make the car fast enough to be entertaining, cheap enough to acquire, simple enough to build and easy to maintain. You may not say, "Miata or C4 with the fenders removed". You might say, "Used sprint car frame with Miata front and rear suspension clips and SBF engine/transmission" OR "Sand rail frame with C4 suspension and Honda engine/transaxle".

Any takers?

Isn't this called a Locost?

Exocet.

atm92484 wrote: Isn't this called a Locost?

/thread

Well, yes, basically, other than I'm talking about a single seat track car with no fenders instead of a two seat street car with fenders. Still, no thoughts on a single seat 818, for example...?

If it has to be single seat then a Terrapin but use a modern fwd car powertrain or a bike engine.

The new Fiesta/2 has all sorts of potential to be a good donor.

stroker wrote: Well, yes, basically, other than I'm talking about a single seat track car with no fenders instead of a two seat street car with fenders. Still, no thoughts on a single seat 818, for example...?

Locost, minus 4 fenders and 1 seat?

I like the little single seater, LeGrand, restore GRM did a while back. You could also look at Dwarf/legends cars. Those hit all the buttons and even run at Brands Hatch

The answer in an earlier Spec class question was Spec Racer Ford, as long as the no fenders part isn't a fixed requirement.

Although a 600 Super Sport class like that is needed given how many people are buying up all the Liter + class bikes for race cars like this. The 600cc version (without restrictors like FSAE) would hit budget and class holes that would be a step up from shifter kart in complexity (has suspension) and aero.

So 600cc LeGrand?

F500.

F600 with 2 changes. Allow IRS and diffs. Allow shocks with 2 conditions.
Spec length and $500/ corner claim rule.

Now we're getting somewhere.

In reply to Flight Service:

YES and Please!

I don't know loads about them, but I'd guess buying up an older FSAE car, throwing out the restrictor and upgrading the brakes and changing the final drive ratio would be hard to beat. Probably not super safe, but that's clearly not the top priority here.

On second thought, those do seem to break a lot...

Would a Formula Vee built with turbo Subie power and Miata suspension bits have enough hp to make up for the added weight and complexity vs a bike motor? Maybe a DeDion axle in back so Subaru hubs could be used and to keep some of the engineering basic enough that the costs to be competitive wouldn't get totally out of hand?

I was going to say almost exactly the same thing as nocones: F600 + basic dampers/springs + 13 inch wheels. I had other ideas on damper cost control, but a reasonable claim rule would work too.

FSAE cars tend to be very fragile. They are built with a weight goal in mind and not durability.

Clemson's cars do very well in the durability category because Michelin, in return for their sponsorship, uses their car for testing through out the year.

You would be better off using a beefed up FSAE build with a minimum weight plus a 250 lb driver. That way if someone is light great, if they are heavy, they can race too.

Formula vee with 6-port 13b rotary engines. Plenty of power, cheap to run. Have a spec damper to keep silliness to a minimum.

F500, for a bit more money, F600.

I dont think you can get much cheaper than those. Especially if you apply Locosting principles to building one. Someone above said them + IRS and shocks. They are missing that the cars work great on a road course without them. They give are within a half second of Club Ford at Summit Point, faster than ITE, and faster than T1. By admission, you are adding almost $3k to the price of one with shocks and IRS (they are chain/belt drive, so IRS would be a fabrication project)

For scratch building something fun? Audi Getrag transaxle, couple with a Ford 302, cram in formula car for a budget F5000

I used to own an FSAE car. They were a lot more fun in college than afterwards.

The recent trend of using the rule book's minimum wheelbase as the mandatory wheelbase is stupid and it creates a car with very hair handling on anything beyond the extremely tight FSAE competition courses. When its restricted its okay but as soon as you remove the restrictor it becomes a complete handful and isn't really that much fun. Spinning at 40-60 mph was annoying. Spinning at 80+ mph is just dangerous.

If you don't have a fairly fresh set of the super soft compound tires they're also no fun to drive. Also the tires need to be at operating temperature for the car to perform. Its easy to do during the 22km FSAE endurance event; not so much at your local autocross. Until they warm up the car is technically neutered and isn't nearly as capable.

Then there is development time for the driver and car. Having full test days lets you try a lot of things and it lets the drivers learn the car. In the solo world its difficult to learn the car let alone improve it by doing six 45 second runs per weekend. At least if it was being used for track use it would give you more seat time but those cars react so quickly that it takes a while for your brain to become faster than the car.

As someone already mentioned you would need to significantly beef up the chassis to some acceptable level of safety. I'm not sure what the rules read now but when I was doing it you needed 1"x0.090" tubing for the main and leg hoops and the three requires tubes for the side impact structure were 1"x0.065". Oh yeah and your feet were 6-12" ahead of the leading edge of the front tires.

If you want to use an FSAE car as inspiration, the wheelbase needs to be at least 72" and the track needs to be at least 50". Personally I'd find something closed wheel since very few tracks do open wheel track days or just buy a F500, FV, or FF and go wheel to wheel if you have to have something without fenders.

Yamaha Banshee donor for all mechanicals - engine, gearbox, cooling/fuel/air/ignition, uprights, hubs, axles, steering etc. . New control arms if necessary to get low roll centers. Scratch-built tube frame designed to be absurdly narrow to allow for 20"+ wide ground effect tunnels on each side. Use 13" tires and cover EVERY surface on the car with impermeable fabric.

Deadskunk got it. Exocet. Use a spec shock like the V-Maxx, a long-lived spec tire like the Maxxis RC-1 on a 13lb 15x7 and either use a dyno-tested power cap or borrow the restrictor sizes from Spec Miata. There's already a class in the UK.

That's assuming that racing is more fun than building.