wheels777 wrote:
David S. Wallens wrote:
So, is it too early to start discussing next year's builds?
What do people want to see?
With your knack for pinching power from nothing, a penchant for the bizarre and your soft spot for Studies; I'm surprised a kickass Stude hasn't graced a Challenge yet.
I'm not asking because I know a limited number came out of South Bend and it would be sacrelige to bastardize one ....
I'm just surprised one hasn't shown up.
Dan
Guideepie:
I believe I left some black caulk in uranus. Can you dig around in there and try to find it when you get a chance?
SVreX
SuperDork
10/5/10 12:44 p.m.
unevolved wrote:
wheels777 wrote:
David S. Wallens wrote:
So, is it too early to start discussing next year's builds?
What do people want to see?
A 1:1 engine to wheel ratio.
Do electrics count?
I figure it would be reasonable to build a car that ran on 4 separate electric motors direct driving the individual wheels. Think similar to the drive motors of a scissor lift. Trade the weight of the motor/ trans for batteries. Gobs of torque, no unnecessary weight like fluids or clutches.
For the Challenge, you don't need much range (which means fewer batteries). You really just need enough juice to run full out for a couple of minutes. After the run, pull into the pits and swap batteries. Budget is calculated by only those batteries that are ON THE CAR. The spares (being re-charged) are kind of like extra fuel.
Wire them to increase the amperage/ voltage to maximize the output of the electric motors.
Voila!
I figure it would be reasonable to build a car that ran on 4 separate electric motors direct driving the individual wheels.
There's been lots and lots and lots of talk of this in our group lately. 1st gen crx's are pretty light...as are festivas...and then there's that Isetta that changed my freaking life this weekend. Hmmmmmmmmm.
SVreX
SuperDork
10/5/10 1:18 p.m.
I've got a Justy sitting out back.
We DO have some experience with hybrid race cars down here...
SVreX wrote:
I've got a Justy sitting out back.
Selling? Might it survive a drive to Texas?
Okay someone needs to buy my Camaro project so I can get this to build for the '11 challenge.
http://nashville.craigslist.org/cto/1935273991.html
poopshovel wrote:
I figure it would be reasonable to build a car that ran on 4 separate electric motors direct driving the individual wheels.
There's been lots and lots and lots of talk of this in our group lately. 1st gen crx's are pretty light...as are festivas...and then there's that Isetta that changed my freaking life this weekend. Hmmmmmmmmm.
What's going on with the chopped Festiva? That sounded pretty cool.
poopshovel wrote:
I figure it would be reasonable to build a car that ran on 4 separate electric motors direct driving the individual wheels.
There's been lots and lots and lots of talk of this in our group lately. 1st gen crx's are pretty light...as are festivas...and then there's that Isetta that changed my freaking life this weekend. Hmmmmmmmmm.
Man I have thought about this and bought parts for it, just never put it together.
First is the controller:
The controller is the bitch in this equation. A big contactor controller with lots of relays in parallel to handle the amps is probably the only reasonable solution. Another option would be a giant oil bathed resistor controller with an external oil pump and cooler. Very inefficient, but your total run time would be less than 10 minutes all weekend so who cares.
Next you need motors:
To get the motors you can part out forklifts. Shop well and each lift will cost you less than $250 and yield 2 motors, several contactors, and $300 worth of scrap metal. Do it twice and you basically end up with 4-6.7" motors for free. With a little timing advancement each one should be able to handle bursts of 120 volts and 1000 amps. Thats 120hp each in a perfect world. In reality each one will probably only put out about 1hp per lb so you are looking at 75-90hp each.
Now the car
The best/easiest car would be one that came with 4wd and independent suspension front and rear from the factory. You take the 4wd hubs and run axles to a diff with flange mounts for the axles in the center. Mount a sprocket between the axle and diff flange and mount a motor on each side of the diff with a small sprocket and you have a simple dual motor chain drive with all the bearings and location taken care of. You can pirate motorcycle parts for pretty much any sprocket ratios you desire.
Now you need batteries and wires
The batteries are where you will spend most of your money. If you shop well you can find optima yellowtops for about $50 each. I was planning on 24. That would give me 240V (with sag) and 1000amps for roughly 240hp considering the efficiency of your average motor. If you mount the batteries really really low you can put your center of gravity below the wheel line and make the car really resistant to lean. For wires you can comb the junkyards. Any car with a trunk mount battery will have 6-10' of pretty good sized cable. Think early BMW's and Miatae. They still are not quite thick enough so you will probably have to double them up.
Some thoughts on wiring
My 24 battery setup would be set up in 2 banks of 12 with each bank powering a pair of motors. If you wire each pair in parallel they each see full voltage with half the amps. A neat feature of wiring them this way is that you get a limited slip effect. If one motor gets loaded down it digs in and pulls harder. If one motor takes off, it gets lots of back emf and produces less torque.
So who is going to build it?
BTW-A big 11-13" motor and a powerglide would be easier and probably just as fast.
AutoXR
Reader
10/5/10 3:10 p.m.
Pulled this out of my motor, blew up @ around the 1/8th mile in 3rd gear
alfadriver wrote:
poopshovel wrote:
I figure it would be reasonable to build a car that ran on 4 separate electric motors direct driving the individual wheels.
There's been lots and lots and lots of talk of this in our group lately. 1st gen crx's are pretty light...as are festivas...and then there's that Isetta that changed my freaking life this weekend. Hmmmmmmmmm.
What's going on with the chopped Festiva? That sounded pretty cool.
Getting back to work on it this Sunday. Seeing that berkeleying Isetta reignited the fire. That, the Haas boys' '49, and the slammed turbo Cherokee are truly an inspiration to build something slightly ridiculous. Tough finding time between all the other projects. The focus shifted to LeMons this year, but both those cars are DONE.
wheels777 wrote:
David S. Wallens wrote:
So, is it too early to start discussing next year's builds?
What do people want to see?
10's are old hat. What will it take to get a car in the 9's?
JThw8
SuperDork
10/5/10 3:39 p.m.
2002maniac wrote:
wheels777 wrote:
David S. Wallens wrote:
So, is it too early to start discussing next year's builds?
What do people want to see?
10's are old hat. What will it take to get a car in the 9's?
Andy to come back when he hasn't just had an appendectomy ;)
oldtin
HalfDork
10/5/10 3:44 p.m.
maddabe wrote:
What would FMV be for a decent TR3 roller? I'm thinking Miata engine/trans.
$650
if the miatas are using v8s - this might need one too or something that takes buckets of boost
9's are serious stuff. I have to decide whether I want to chase 9's next year or build an oddball car. I'm half tempted to build an autocross and drag monster and give the middle finger to the concours. Holy crap some of the detailing was over the top impressive! I don't think I could make a car that clean if I spent the entire next year just detailing.
oldtin wrote:
maddabe wrote:
What would FMV be for a decent TR3 roller? I'm thinking Miata engine/trans.
$650
if the miatas are using v8s - this might need one too or something that takes buckets of boost
Miata motor will handle 220-240hp with ease.
oldtin
HalfDork
10/5/10 3:55 p.m.
Is that enough??? I'm thinking weight to power needs to be somewhere in the neighborhood of 6:1 if not better. I think they weigh about a ton stock.
oldtin wrote:
Is that enough??? I'm thinking weight to power needs to be somewhere in the neighborhood of 6:1 if not better. I think they weigh about a ton stock.
Well do the boost with megasquirt and an ebc and you can turn it up for the drags. Spare 1.6 Miata motors are throwaway cheap.
You'll need to grow a mullet.
oldtin
HalfDork
10/5/10 4:20 p.m.
It's not a mullet - it's a Guido
poopshovel wrote:
Getting back to work on it this Sunday. Seeing that berkeleying Isetta reignited the fire. That, the Haas boys' '49, and the slammed turbo Cherokee are truly an inspiration to build something slightly ridiculous. Tough finding time between all the other projects. The focus shifted to LeMons this year, but both those cars are DONE.
It is a huge compliment coming from you. I want to see that Festiva win it all like the Superturd should have in '07.
If all you guys don't mind we'd like to bring the Cherokee back in '11 with a few new twists and a turbo that is (SHOCKING) installed BEFORE the event and actually tuned.
I can't believe we have to wait a whole year! We had so much fun this year. I can't wait until October 2011!
oldtin wrote:
It's not a mullet - it's a Guido
Man first he inspires some never competed before board member to make a sticker, now he has a hairdo named after him. The clowns helmet size is going up.