Head Ball
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Dedicated track car build - 2007/10/16 19:29
I am going to move my track car project into this forum. Most of the information below was copied from the "Projects" tab on the forum. From now on, all updates will be posted here.
Background
For years, I have had thoughts of building my own car. In college I designed a single seat, mid-engine, VW powered car with a group of buddies. Ever since, I have told myself I would build the car. After sitting out a few track days because of various issues with the Vette and Camaro I decided the time had come to follow through. My original plan was to make a single seat car powered by a SRT-4 engine/trans combo positioned in the middle of the car. Think Ariel Atom. Then, I saw a car at a golf course that changed my mind for the better. What I saw was a homebuilt car based on a C5 Corvette powertrain and suspension. I stared at that car for 20 minutes taking in all the details I could. Afterward, I knew I had to have a V8. So, the current plan is to build a mid-engine, two seat, LSx powered car for the track.
Trans
The key to a V8 powered mid-engine car is the transaxle. There were/are very few cars from which to pull a transaxle that can handle the torque of a V8. The options include Audi, Porsche, VW, Ford GT40, Ford GT, Corvair, and a few other European makes that weren't really imported to the US. All of them have some sort of weakness. The Audi transaxles are not easy to find now that the replica GT40 people know about them, and many people question their ability to handle a V8. The Porsche transaxles have to be flipped up side down, so the half shafts have to run at a larger than desired angle. The VW based transaxles can be made to take the torque, but your pay the price. Starting price for a VW based transaxle for this power level is $9500. Price is what excludes the Ford examples as well. Apparently, Ford will sell you a brand new GT trans...for $14,000. I am still researching my options, but right now I am leaning towards the Porsche G50 transaxle from a 911. The entry fee is higher, but it should hold up to the LS engine with no problems. I will see what I can do with the rear trackwidth to reduce the angle of the half shafts.
CAD
As much as I want to just buy some tubing and start cutting and welding, I figure, as an engineer, I should probably do some design work first. I decided to take a CAD class because I don't have much experience with the modern CAD packages. I chose Unigraphics because I have access to it and people that use it regurlarly for those times I run into problems. I'm about half way through the class at OCC, and I have picked up a lot of tips and techniques, but we still haven't gotten to what I want. So, I have been trying some things on my own.

This is the first part for the car that I have modeled. I made the vanes curved for no other reason than I wanted to learn how to do that. Making the vane curved wasn't difficult. What was difficult was constraining it so that I could change the overall shape of the rotor and the vanes would change as well. I went through about 4 iterations before I came up with something that worked. Now, I can change the diameter and thickness of the rotor and the complete model updates without crashing. The next item will be modeling a C5 spindle. I ordered it from a Vette parts place, and I will get started as soon as it shows up.
Post edited by: Head Ball, at: 2007/10/16 19:33
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