Lightweighting - Is there such thing as too far?

In reply to neon4891:

In Michigan you don't need a windshield if you wear eye protection.

This is brilliance

I love this concept. So much cheap and so much fun!

Kenny_McCormic wrote: In reply to neon4891: In Michigan you don't need a windshield if you wear eye protection.

Is there a version of Michigan that isn't frozen and salty half of the year?

In reply to HappyAndy:

Think of it as forced cyclic project car work, and its more like 4-5 months out of the year in the lower peninsula.

I like the idea. I'm in the process of building something similar using a C4 Corvette. I purchased the driving Vette for $700. It was running and driving but the body and interior were completely trashed.

I started the same type of project using a Miata as well. I have one that I was going to use a single hoop for the street. And, I purchased a supercharged one that I'm stripping down and building a full cage for.

I also built a frame with a 95 inch wheelbase to bolt the Miata suspension and drivetrain into. The engine is moved further back and is lower. I'm fitting an old mid engine can am style body to it and using a Porsche 550/356 Spyder windshield.

To many projects. To little time. Plus, some health issues slowing me down. But, having fun.[URL=http://s1143.photobucket.com/user/jmcbigbelly/media/c4blastside8-7-2014_zpsf7c59cf3.jpg.html][/URL]

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A Miata like this (extremely stripped) came out to an autocross we had in Sarasota. It kept swapping ends. The relatively light rear gave them No rear grip.
The car may have been out for an initial test, so maybe they figured it out later on, but I don't think they had any good runs.

Colin Chapman had a knack for finding the edge of "too light", with a few of his race cars physically breaking apart on-track. One driver (can't remember the name) lost a wheel due to failed suspension. At the party after the race, a cake was being served, one with an image of a race car on it. The driver cut out the portion of the cake with the front tire on it and served it to Chapman, mentioning something like, "this is your piece."

spin_out wrote: A Miata like this (extremely stripped) came out to an autocross we had in Sarasota. It kept swapping ends. The relatively light rear gave them No rear grip. The car may have been out for an initial test, so maybe they figured it out later on, but I don't think they had any good runs.

This demo car has already seen solid track time. The drivers claim that despite the 60/40-ish weight distribution the handling is still very direct and forgiving at the limit. Moving all of the car's weight inside its tire footprint seems to offset the majority of the weight imbalance.

Chassis #2 is in teardown now. After some seam welding it will get a redesigned rollcage based on what they learned from building and driving the first car.

spin_out wrote: A Miata like this (extremely stripped) came out to an autocross we had in Sarasota. It kept swapping ends. The relatively light rear gave them No rear grip. The car may have been out for an initial test, so maybe they figured it out later on, but I don't think they had any good runs.

Sarasota, huh? I'm in Bradenton and I was at the autocross you speak of. "The Beast" that Miata was called and I remember it having traction problems all over. I youtubed "the beast miata" and there are videos of him pulling FTD's all over the place, including the "Bay Bottom Crawl" down in the Keys. He must have gotten it sorted out.

Most amateur racers won't want to do that because you HAVE to have a garage or space in your garage to have a completely naked track car or a cover for rain and snow. It also doesn't look visually appealing and plenty of states will require windshield wipers, all the safety lights, and a windshield. I would go with Corbeau fixed back seats, personally.

In reply to kb58: That's hilarious!

jmc14 wrote: I like the idea. I'm in the process of building something similar using a C4 Corvette. I purchased the driving Vette for $700. It was running and driving but the body and interior were completely trashed.

That's awesome - a stripped and gutted salvage Corvette chassis would be a potent track day weapon indeed.

Mr_Clutch42 wrote: Most amateur racers won't want to do that because you HAVE to have a garage or space in your garage to have a completely naked track car or a cover for rain and snow. It also doesn't look visually appealing and plenty of states will require windshield wipers, all the safety lights, and a windshield.

I ran into that problem with my old ChumpCar project--only after the glass was all removed did I realize that my storage options for the car had become very limited. On the other hand, some back of the envelope math suggests that I could fit three, or maybe even four, of these things in my two car garage ;)

The cars will be sold with lights and exhausts. I'm thinking that a quick-and-dirty plexi/lexan 'windshield' would be pretty easy to fabricate. For states that stipulate wipers, does anyone know whether the wipers need to be powered?

I'd want it to be weather resistant, so I could use it as a daily in place of a motorcycle. I wonder if the MPG would be improved or negatively affected now that it's aero pretty much blows.

HappyAndy wrote:

Kenny_McCormic wrote: In reply to neon4891: In Michigan you don't need a windshield if you wear eye protection.

Is there a version of Michigan that isn't frozen and salty half of the year?

North of the 45th parallel or so, it gets too cold for salt to work. So it is frozen 8 months of the year and you see people driving 80s Subarus that look brand new, which might also be evidence of time travel.

It would add weight but why could you not just add monster tires to the rear to bring the balance back in line.

iceracer wrote: Weight doesn't have much effect on straight line speed. Of course it helps acceleration off the corner so you get there quicker.

I think you mean that cutting weight doesn't help top speed that much, but top speed isn't the goal - acceleration is. Racing doesn't involve a lot of long top speed runs.

Here's a prize length lightening thread on a Fiero group. The guy chops everything he can and still have it look like a Fiero: down to 2100 lbs.

http://www.fiero.nl/forum/Forum2/HTML/112942.html

dculberson wrote:

iceracer wrote: Weight doesn't have much effect on straight line speed. Of course it helps acceleration off the corner so you get there quicker.

I think you mean that cutting weight doesn't help top speed that much, but top speed isn't the goal - acceleration is. Racing doesn't involve a lot of long top speed runs.

At low speed, acceleration is about power-to-weight ratio, at high speed it's more about power-to-drag. Cutting all the bodywork off like that is not going to improve the drag ratio.

It doesn't have to be a top speed run -- at local tracks Miatas see plenty of time at speeds above 80, and drag matters at that speed.