Car conversion to 3 wheels

[master_of_disaster]

Hi ecomodders,
I just joined this website/forum.
I found it while searching the net for pictures/designs of a car converted to a 3 wheeler.
My idea for an ecomod is to use the front end of a fwd car (2 front wheels, engine and all) up to the steering wheel and chop off the back part and connect a roll bar cage for side by side seating and one wheel in the back.
The shape of the cage would be tapered for aerodynamics and can be covered with fabric (like that used for convertibles) or molded plastic or fiberglass.
But the main idea is to reduce the weight of the car by maybe around 40% (or more) and improve the aerodynamics.
A lot of the parts from the chopped off part can be reused in the conversion such as seats, lights, rear wheel, brakes, windows etc.
Safety should be somewhere between a car and a motorcycle, and might be equal to a car's if you factor in agility, braking distance and the rollbars.
I think performance would be in the sports car level.
This can vehicle can then be registered as a motorcycle.
What do you think ecomodders ?
MoD

[Weather Spotter]

might be worth a try, we are open to seeing pictures of most any car mod, or planed mods.

[master_of_disaster]

I guess its kinda hard to imagine so a drawing is a good start if I need to solicit advice.
Thanks for the suggestion.
Eric

[MTrenk]

I believe you are on the right track with the wheel layout. Anyone who has tried to turn a 3 wheeler with one up front and two in the back at high speeds quickly finds out what a dynamic disaster they are! (How companies are even allowed to sell them with the one front wheel configuration is beyond me, it's unbelievably unsafe...)

The only issue I have with front wheel drive is that unless you plan on creating downforce in the rear for high speed driving, front wheel drive will essentially leave you floating on high powered casters up front, which isn't really very safe.

In my search for vehicle dynamic heaven, two wheels up front and one in the back, plus rear wheel drive seems to be the stairway.

Suspension and weight transfer issues are still bothering me, but we aren't trying to pull 2 lateral G's.

I know a lot of people on the forum equate downforce and drag, but lift causes drag too, so if I had to choose, I'd go with downforce (more tire grip -> better handling -> not flying off the road from a 40 mph crosswind).

If you're really going to move forward with this, I would be happy to assist you in your design! When reducing the weight of the car by such a large amount, you're going to need completely new spring rates, maybe even new damping (shock absorbing) rates, a new suspension design for the rear wheel so you don't break your back, and a bajillion other things. Well, need is my opinion, but I try to design things I can't kill myself in.

[Frank Lee]

Are you related to Hermie?

[MTrenk]

I don't believe I am related to anyone named Hermie. Sorry to disappoint you.
My great uncle designed the vector thrust control system for the Challenger space shuttle, worked for NASA for 33 years, then they had to call him back because they found one of his valves in a field in Kansas and asked him how it worked so well and how he designed it. :P
That's about all I've got that's noteworthy in my family from an engineering standpoint.

[Frank Lee]

Oh. Hermie believed in cars taking flight too.

[tortoise]

Originally Posted by master_of_disaster

My idea for an ecomod is to use the front end of a fwd car (2 front wheels, engine and all) up to the steering wheel and chop off the back part and connect a roll bar cage for side by side seating and one wheel in the back.

I like tandem seating for such trikes. You can lower the frontal area substantially, a teardrop shape without a long rear overhang is possible, and as a motorcycle, a more easily made plastic (versus glass) windshield can be used. The longer resulting wheelbase alleviates the weight transfer off the rear wheel under braking.

[master_of_disaster]

Max,
Hadn't thought of the spring rates, damping issue yet, but did worry about the traction of the rear wheel.
That is also why I'm planning to install a "very" big and wide wheel at the rear for my project, to increase traction and add to the "cool" factor.

Of course, safety is the number one concern, especially since if this works out, I might even do a business out of it.
Buy a wreck with a working front end for $500, chop off the back, put in the cage, seats and rear wheel, attach all the connections such as brakes, steering wheel, electronic wires, etc and viola sell it for $7000.
Should be worth it for a safe, economical, and fun to drive trike, right ?

I am still in the idea stage but I could definitely use the "brain" of an engineer since I'm just an I.T. guy who does mechanical and welding stuff as a hobby. Doing it with somebody also adds to the fun instead of just doing by yourself. So yes I'll let you know when I start the project.

Maybe we start now....how do you think the suspension for the rear should be...I think a swing arm is the only option like a motorcycle rear suspension ?
Eric

[master_of_disaster]

Originally Posted by tortoise

I like tandem seating for such trikes. You can lower the frontal area substantially, a teardrop shape without a long rear overhang is possible, and as a motorcycle, a more easily made plastic (versus glass) windshield can be used. The longer resulting wheelbase alleviates the weight transfer off the rear wheel under braking.

I did consider tandem seating since it is the more "aerodynamic" option but when I factor in commercial appeal, the side by side seating is preferred, I think.
The existing steering wheel is also on the left side so moving it dead center would need a lot more parts than just moving it slightly to the center.
Eric