In reply to Robbie :
Would the cars need to have roll cages?
We could all probably drink all the beer we want while the race is going on, too.
In reply to Robbie :
Would the cars need to have roll cages?
We could all probably drink all the beer we want while the race is going on, too.
In reply to volvoclearinghouse :
Yep. That gives me confidence that it's the right answer.
To make this practical and inexpensive we've got to build a car that's a helluva lot smaller and lighter than a CRX. Capacity scales linearly with weight and volume - length cubed, cooling scales with area - length squared. Hitting the initial goals of the DeltaWing for weight and drag are a good start.
Jaynen said:The whole "rest of your car has to be 500 bucks" thing sort of makes it very hard? Or is the "500" dollar thing not really enforced?
Well the judges can be bribed. But if they deem it really cheaty you’ll get penalty laps
chaparral said:In reply to volvoclearinghouse :
Yep. That gives me confidence that it's the right answer.
To make this practical and inexpensive we've got to build a car that's a helluva lot smaller and lighter than a CRX. Capacity scales linearly with weight and volume - length cubed, cooling scales with area - length squared. Hitting the initial goals of the DeltaWing for weight and drag are a good start.
Me too. If one idiot comes up with a number, that's one thing, but two idiots, working in two different independent ways, coming up with virtually the same number, well, we have a name for that.
Engineering.
Aero drag and rolling resistance are gonna be two big hurdles. Unfortunately, LRR tires are about the worst thing you can run on a track, and sticky track tires are about he worst thing you can run for efficiency.
They've really clamped down on the rules lately for body modifications, modifying OEM crash structures, etc. Some hyper-miling tricks would be OK, but a full-on Delta-wing swap is probably not going to fly. 
Likewise anything too much smaller than a Hillman Imp.
Other than all of the big challenges of fielding an EV. There are those damn 300hp V8 cars with 50 gallon fuel tanks running for 2.5 hours between stops with an average lap time of 1:50 on a two plus mile track. I'm no where smart enough to figure out how to do this with an EV. Now if you only had to beat class B or C it gets more interesting.
Even if you could run slow and low for five hour stints, those bitches are hard to catch.
Our best showing was fourth in B and 14th overall running slow and consistent 1.5 to 2 hours between very slow pits. The name of the game here is survival.
All of my thoughts would tend to lead to putting the battery packs under the floor. FWD vehicle would be better for this. Using a battery terminal from a forklift would probably be sufficient as a quick connection. Not over heating and having enough capacity without too much weight or too many stops is going to be the barrier that will hold everyone back. Having enough batteries to charge in between re-use will just end up being a money issue.
In reply to volvoclearinghouse & chaparral :
so, what you need is a small, rear engined, rear wheel drive car, that you can add big rear wheel arches to, and then extend the front end for delta wing?
Another way to stretch the rules- you know how all those cyclists set LSR's out on the flats? They use a lead vehicle to break the wind. Build some huge brick of a vehicle with 300 HP to run in front of the EV, and it'll probably double the range, no extra batteries needed.
volvoclearinghouse said:Another way to stretch the rules- you know how all those cyclists set LSR's out on the flats? They use a lead vehicle to break the wind. Build some huge brick of a vehicle with 300 HP to run in front of the EV, and it'll probably double the range, no extra batteries needed.
Don't you already have some huge brick of a vehicle with 300hp?
In reply to Robbie :
Are you referencing this?
In reply to volvoclearinghouse :
With the amount of time we'll spend cornering the reduced cornering drag of using a sticky radial will result in less drag around a lap of the circuit than reduced straight-line drag from a LRR tire. It'll also give the driver a lot better accident avoidance which is the real key to winning LeMons.
A track-capable EV is not going to look anything like a track-capable ICEV. Whatever it is it can't be too much larger than a converted F500 car, and an enduro kart would be even better. The car will need a very big plywood fin with a gold-bordered American flag on it just to be visible.
In reply to chaparral :
Agreed about the tires.
I understand your point about size and mass, however it still has to meet LeMons rules, which means it can only be so small. You'd potentially be dicing it up on truck with things like that black beast 2 posts up ^ so you'd want something with some substance to it. Realistically, the 82" wheelbase is the working lower limit to practically cage it per the rules and fit the driver, batteries, motor, and all the other attendant gear. The DeltaWing car has a cD of about .35; I'm sure this would be possible to hit or better even with a somewhat more conventional design. It won't need as much downforce or be running 200 mph, either.
volvoclearinghouse said:Another way to stretch the rules- you know how all those cyclists set LSR's out on the flats? They use a lead vehicle to break the wind. Build some huge brick of a vehicle with 300 HP to run in front of the EV, and it'll probably double the range, no extra batteries needed.
This for the win. A three car team with an EV in the middle, just bump drafting along most of the time. Who needs an extra driver?
volvoclearinghouse said:Another way to stretch the rules- you know how all those cyclists set LSR's out on the flats? They use a lead vehicle to break the wind. Build some huge brick of a vehicle with 300 HP to run in front of the EV, and it'll probably double the range, no extra batteries needed.
There's the plan. If you get a fast enough "chase vehicle", you'd be all set. Given the really amusing bodies that are commonly seen at races, this would be pretty darned easy to put together. And cars are constantly that close to each other.
I don't see that as any stretch of the rules- that's partnering with another car to provide a lot less drag.
akylekoz said:volvoclearinghouse said:Another way to stretch the rules- you know how all those cyclists set LSR's out on the flats? They use a lead vehicle to break the wind. Build some huge brick of a vehicle with 300 HP to run in front of the EV, and it'll probably double the range, no extra batteries needed.
This for the win. A three car team with an EV in the middle, just bump drafting along most of the time. Who needs an extra driver?
So the follow car can be a cop car with the pusher bumpers. Just need a killer cooling system for it since the rad will be largely useless.
Also, your lead car and follow car can be really cheaty and take tons of penalty laps. You don't need them to win.
Bump drafting will get you a black flag. Too many BFs and the team could be kicked out. Or put in time out for a few hours
This bad boy runs for 24 hours on batteries, and makes 1500 HP!
Robbie said:Also, your lead car and follow car can be really cheaty and take tons of penalty laps. You don't need them to win.
Bingo.
In reply to alfadriver :
I think what will govern size is more likely the battery pack you want to run. If you want a floor-pan sized battery pack like Tesla you need a floorpan of similar dims. Speculating based on electrocet, the Miata floorpan is only big enough for 50-60kwhr, so you need a fairly sizeable car to get 100kwhr or whatever your target is. Also, you are adding ~1000lb of batteries to a car, so the chassis is going to need to be strong enough to handle that.
In reply to volvoclearinghouse :
82" wheelbase is fine - I think it'll actually end up somewhat longer than that to fit the pack, cabin, and motor within it.
Getting the same 0.35 drag coefficient as anyone else is a big advantage if the frontal area can be reduced by being half as tall and 2/3 as wide.
I am thinking that the only way around the charging time is to use a large cap bank. You would also have to recharge the charging station in the pits between pit stops with a generator or something. Maybe another big cap bank in the pits. Yes there are possible issues with it exploding or catching on fire but hay that is just an engineering challenge.
alfadriver said:So the follow car can be a cop car with the pusher bumpers. Just need a killer cooling system for it since the rad will be largely useless.
Follow car just needs a rear-mount radiator with big scoops 
sergio said:Bump drafting will get you a black flag. Too many BFs and the team could be kicked out. Or put in time out for a few hours
No real bumping just a lot of consistent drafting. With cheaty class A cars that have really big fuel cells. If you can figure out an E Lemons car how hard would adaptive draft control be to rig up, set the cruise and required following distance.
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