|
Mitchell Software, WinGeo, BumpSteer, and RollCenter Back when designing Kimini someone gave me a copy of Mitchell's WinGeo. At the time it was a DOS-only program used to develope suspension, determine roll centers, calculate bumpsteer, and so on. Fast-forward to a year ago; I decided to use WinGeo again because of how well it worked for Kimini. However, my conscience got in the way since I hadn't exactly paid for it back then, 12 years ago. I also hoped that over the years the program had be improved and expanded - it has! One cool thing is that when you call, more often than not, William Mitchell will answer the phone himself. In these days of outsourced-product support, it's nice to talk directly to the designer. WinGeo does everything and now includes a GUI to show suspension motion. It has a ton of menues, no doubt collected via suggestions over the years. Besides WinGeo's geometry design are two related programs, BumpSteer and RollCenter. While WinGeo calculates both, these routines handle only the one function so they run much faster. It's pretty awesome using BumpSteer; it made short work of the usually time-intensive process of trying a million pivot points for setting the steering tie-rod ends. The best part is that as the pivot points are moved about, a graph updates to show the resulting bumpsteer, live. RollCenter is a very helpful graphical explanation of the various forces in the the chassis, including a cool animated explanation of Mitchell's "Force Application Point", a more correct method of suspension design than the traditional kinematic roll center method. |
|
Alibre CAD software (If you want to try Alibre, please do me the favor of using this link. It costs nothing to do so, and thank you!) Way back when I started designing Kimini I used Turbocad. At the time it worked - just. I got really tired of its quirky nature, how things were organized and how to activate various controls. It finally crashed so bad that it wouldn't even reinstall; I got so frustrated with it I finished the project without it. I know Turbocad is still available but just couldn't bring myself to buy it - too many bad memories. I can't help but suspect a lot of the quirky infrastructure is still in it. Fast forward to this project, and I find myself needing a CAD system again. This is important because unlike Kimini, I want to have the entire design in the computer before I start cutting metal. Some time back I got a chance to use Solidworks but it's flat out too expensive, somewhere between $3000 and $8000, plus about $1200 a year in maintenace! That's fine for real businesses but for "the little guy" it's completely crazy. I can't in good conscience use an illegal copy, which lead to a search for alternatives. I found the products from Alibre and they're very promising; it's reasonably priced and they even offer a free (though somewhat neutered) version you can try out first. (Just so you know, when you download the free version, be aware that you will likely get a sales call. It's up to you what phone number you put ;). Anyhow, I'm pretty impressed with what it provides, way more than enough to build an entire car on a PC without lifting a wrench. One set of features I really like is the multi-level help structure. Everything from FAQs, to "Live Help", to forums, to what I call, "Really, Really Live Help". That's where you let the Product Support guy take charge of your mouse and shows you how to do what got you stuck in the first place. Very cool and something I may find very helpful! I will expand this as I learn the system. [Update] Alibre's not going to like this... I put most of the blame on myself, not having the patience to learn it enough to use. The embarrassing thing is that I did learn and use Google Sketchup, using it to create all the 2D and 3D drawings. |
|
WaveTrac limited-slip differential: In late 2007, Autotech, the U.S. representative for Quaife, stopped importing the gear-based Quaife and came up with their own, called the WaveTrac. It's a gear-based LSD with the advantages of a Quaife, but also contains clutch-type action to handle the weak point of the Quaife, losing drive when one wheel lifts (like when you drive over a berm when on-track.) When I bought mine they'd just come out so I've yet to hear if its hype is warranted. I hope so, because I have it in my transaxle! |
|
Locost-type fiberglass parts: After dealing with the composite for Kimini I vowed to avoid working with the stuff. Instead, I ordered a full set of Locost composite, front and rear fenders, plus a very low profile nose, from Kinetic Vehicles. Doing it this way saves a TON of time, mess, and bother. |
|
Battery cutoff switch: Kimini doesn't have a battery cutoff switch, which always bothered me; what would I do if the wire harness started smoking? The risk of fire is big enough that I wanted a switch on the next car, and here it is. My brother uses this one and I really like it. The nice thing is that it's a twist-to-turn-on/hit-to-turn-off. That's a nice setup, where turning it on takes a deliberate effort, yet in an emergency, the driver can quickly smack it to shut things off right now. It also includes connections to disconnect the alternator field winding. |
|
Honda K-series exhaust flange: BMC Racing Products carries a wide array of CNC-machined flanges, important when making headers. I ordered the header flange from them because they're the only vendor I found that supplies 1/2" thick stainless flanges; for the turbo I'm not taking any chances. It's a small business, so it took a couple weeks, but the finished product is perfect. Sam, the owner, was quick to let me know when it would be shipped. |
|
Honda K-series A/C and PS eliminator: Swappin a Honda K-series engine into a lightweight car typically means eliminating the A/C and power-steering. However, doing so presents a problem due to no longer being able to route the belt to drive the alternator and water pump. This adaptor does just that, moving the alternator down to where the air-conditioner used to be. A perk is that it lowers the alternator from its original position by about a foot. |
|
Griffin radiator: This is an aluminum, two-row, 3"-thick radiator. The best part is that it's two-pass, meaning coolant is forced to cross the cooling core twice. This prevents coolant from favoring just a few rows along the top of the unit instead of distributing the head evenly across the core. Testing has shown that doing this improves heat transfer nearly 40%. Between that and it being two row, aluminum, and 3" thick, this should be able to handle the turbocharged engine. When I can, I buy parts from circle-track suppliers like Summit Racing. In general, they are cheaper than true "road-racing" shops. |