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Project Vehicle Build


Nemesis47
11-07-2015, 02:21 PM
Greetings,

I am new to Af and was hoping I could get help regarding my build.
I researched a bit and found the data on the net quite overwhelming and it needs to narrow down,and as this vehicle is going to be custom scratch built, I am not getting many straightforward guides to building one.

As I live in India, there are going to be a lot of limitations. People here don't really do anything out of the box. So most of the services and products available "down the lane" or "in the local hardware store" in the US simply don't exist here.

So the First thing being the budget, is limited to 10000 USD.
The chassis would be a space frame one and the curb weight is to be under 1300 pounds.
The minimum rwhp required would be 300. 500 rwhp being desired.

The first problem that arises is that there aren't a lot of naturally aspirated engines available that would meet the requirements.
Available to me are engines that make 100 to 150 bhp or some of the audi group and bmw engines which make 250 hp but cost a little bit more. An obvious answer to these problems would turbocharging them. And changing internals would be a tough job.

So what motors with stock internals could hold around boosts of 14 psi with an initial horsepower of 200 or more hp.

Or if I have no options but changing internals, what motors are best for what amounts of boost after changing what internals?

The second and the most difficult problem is the transmission. It happens so that I want to build a Mid engine rear wheel drive Drive train and in order to do that you need to have a transaxle. And the transaxle needs to be able to withstand the power too. I don't know where to find one or how that fits into the vehicle.

The third problem being the suspension- finding the right suspension for this type of vehicle.(Will solve this after the first two problems).

And there is lot to learn and a long way to go.
Hoping to get some advises and tips.

Cheers
Muneeb

Black Lotus
11-09-2015, 07:19 PM
You do know that when you get 300+ HP going thru a transaxle that you have to get a pretty beefy piece of kit. Porsche or Audi ($$$) Less HP, or torque is less money-- Air cooled VW Beetle (turned around) or Subaru. If you don't mind a transverse engine, with probably not much power, you can convert some sort of Toyota FWD, and stick it in the back.
https://www.youtube.com/watch?v=LoA_ZwUWat8

With a tubular spaceframe, you should have all the suspension pickup points thought out already so you DON'T end up with suspension rod ends pointing at (and attached to) the middle of a tube.

Or you could wait a little and get more money and buy a used low end mid-engined car that's ready to go.

Nemesis47
11-11-2015, 10:22 AM
Yeah, I think the transaxle will have to go. But I still will put the engine in the middle with automatic transmission immediately coupled with the differential. Might take up some space but should get the job done according to calculations.

No, its not just about owning a vehicle. As an about to be engineer I would like to build my own vehicle.

shorod
11-11-2015, 12:32 PM
Have you considered building an electric car? That solves a lot of the drivetrain issues since often the electric motor does not require a transmission and the controllers, batteries, and cabling can be mounted with greater flexibility and less precision than is required for a home-built internal combustion setup. If you're really wanting mechanical engineering experience (you didn't mention which Engineering field you are finishing up) you can still get that in the battery location method, weight distribution, center of gravity, suspension, chassis, steering, adapter plate for the electric motor, etc.

-Rod

Nemesis47
11-12-2015, 01:35 AM
Yeah I am currently in the second year of my 3 year mechanical engineering course, which, if all goes well, shall be followed by a B.E. in aeronautics.

I have researched electrical systems and although they are simple , it will cost you very much. Its all about hard to get specialized electric motors and battery packs. And even then it would be difficult to make it half as good as tesla.

And the conventional system, although complex, with some tunes and a turbo, you got a beast on the road.

Dave B.
11-13-2015, 08:56 AM
One option you might consider would be to use the transaxle set-up GM produced in the late '60s/early '70s for the FWD Oldsmobile Toronado and Cadillac El Dorado. The associated engines both produced relatively high horsepower and torque numbers. The downside would be that they are neither light-weight nor 'clean', but both those problems could be somewhat mitigated with the use of aftermarket parts.

The elephant in the room, of course, would be 'switching' the power output to make the rear wheels rotate in the opposite direction. I'm 99% sure that this has already been done in the after-market, but I don't have any links to provide for you. I do remember one project in which a Toronado drive-train was transplanted into the back of a Pontiac Fiero. I didn't see the finished product, but the most memorable part of it (for me) was the size of the fender flares required to cover the rear tires! (The builder did not want to change the width of the Toronado power-train - he just wanted to use lower profile tires...)

As far as the space-frame goes; if I were you, I'd be looking at the designs for both rail buggies and specialty cars like the Ariel Atom. I'm not suggesting that you copy someone else's design, but studying existing road-worthy vehicles could give you insights into solutions to problems you might not have yet considered.

In any case, good luck with your project! And, of course, please keep us updated on your progress...

Dave B.

Nemesis47
11-13-2015, 12:46 PM
I agree that the GM produced transaxles might be a good option but I cannot get my hands on them. Its very tempting to buy a motor from ebay which I cant find here, specially the corvette engines, but the shipping costs are really high which add to the already expensive engine.

I got the idea of building a space frame chassis from the ariel design itself. Although the ariel atom has a bit formula-ish look to it, I intended to give my build a road car look.

And as for the updates, I don't start building till mid 2016, got plenty of time to research.

Muneeb

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