Sam and I wanted to try this simply because we observed some of the top cars doing it, and we had some ideas of why it would be superior. Unfortunately, this last year, we had a lot of other bugs in our car with our batteries and gearing to really be able to assess the front-wheel drive system. I heard that another school (I think Willamette) has tried front-wheel steering designs in the past, but doesn't do it anymore. On the other hand, Cloud swears by it. What are the opinions out there?
The front wheel drive and steering system is great if it is done 100% correctly. The head stock needs to line up directly so it would hit exactly were the tire hits the pavement. The rake on the headstock is also a critical angle but I can not remember what that angle is. If these are not dead on then the car will plow when you try to turn and you will continue to travel for a while straight when you try to turn. We have made about 6 to 8 of these over the years and have had two that handled well. But one of the those was built too light and had mechanical problems holding up on races like Hood River with the BIG pot holes. The other one from about 12 years ago worked well. It was about 8 feet long so the wheel base was fairly short and the steering was dead on. I think Jedd took 4th or 5th in the state with his car. The NorthWest has never had a high school state champion car that was front wheel drive--they have all been the tri-car design with 2 steering wheels in front and one drive wheel on the back. Another problem is to have the motor turn with the front wheel and not have mechanical problems with it. Most of our cars have figured this part out but it has been a problem on some cars. I don't think that students get the steering done quite right---I think a great student car could beat the tri-cars on short track races and I know they could at PIR.
Mark Bray from Thurston High is planning on making one this year and he is trying to get hold of the Pak-Lite team that has a car that will out-corner mine as far as the speed it can take a tight corner and with the added efficiency of front wheel drive is hard to beat. There short track cars are about 7 to 8 feet long and very light weight and set up differently than their long track cars that are around 10 to 12 feet long. They used to race with us on any Sunday race as their religion keeps them from racing on Saturday. Unfortunately they did not race last year and possible not the year before so most students have never seen their short track car. They did bring a couple of their long track cars to PIR two or three years ago..
The cars built by Dave Cloud of course also use front wheel drive and do great. These cars are longer and tend to take corners wider at high speeds but again because of added efficiency they are very difficult to beat. There of course is not ANY tire scrub on corners as the back tires are perfectly lined up and have great bearings. They can coast nearly all the way around the 1.92 mile Portland International Raceway track if they desire. They can get up to speed (~50) on the straight and then let off and just coast back onto the straight again. They used to, and maybe still do, just give the car power on the main and back straights and coast the rest of the race. I know they used to have trouble on the tight tracks when we first started the series of short track races a few years back but Dave has worked out the bugs and his cars now corner great but again because of the length have to corner a little wider like a Caddy as opposed to a BMW Z-3. If the corner is tight like the inside left at Lacey or the corner at the bottom of the big hill at Hood River they have to slow down a little to make it around where my car will just take it at full speed.
My tri-car is less efficient because you can not get rid of ALL of the tire scrub with two wheels turning. I also don't roll as well as the Cloud or Pak-Lite cars with my rear wheel drive and less expensive bearings. But I can take tight corners at higher speeds so I don't have to speed back up. If I time it right I can be a little behind the Clouds going into a corner and sling shot my way past them as we come out of the corner. But they out accelerate me and leave me again in the straights. If there are enough corners and short straights I can usually stay fairly close to them and even beat them some times--even on races they don't break down or have a flat.
Good luck--looking to see your success this year on the track.
From a driving perspective I think it is a lot easier, and safer, when less experienced drivers have two wheels in front. It creates a whisker effect, you aren't going to try to fit through a space you cant (ideally). Though the cars are less stable in many ways. Built correctly front wheel drive is much more logical. There is not a track that you will not be able to make the corner on, you have to if your car meets standards. Like Mike said, while you may have to slow down, the aerodynamic and effectiveness of the vehicle will make up for it everywhere else. Not to mention in 20 years one of our cars has never flipped, despite how fast or tight we take a corner. Rarely do the Cloud cars get beat if something does not go wrong. PacLite, despite not running often build remarkable vehicles, they are also one wheel in front. They have proven that it is possible to corner just has hard if you build a car that is meant for a tight track.
I have always thought it curious that no northwest high schools attempt it, or not many anyway. Even if it doesn't start out perfect, I think with fine tuning you will come out with a successful vehicle. You don't need a fancy set up. The best cars, be it high school or adult, are not the most expensive (despite what people think my dad puts very little money into his cars, just a LOT of time). They are the cars that owners spend time going over every little thing with a fine tooth comb. I don't know off the top of my head but last year there was a high school car that had been passed down from the year before having been just mediocre. But with the next student going over everything he managed to make quite a competitive car.
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