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xromad

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Everything posted by xromad

  1. Drew, it was great to meet you this winter. Your post reminds me that we need to get together for a "Blat". I drove the Stalker to work 3 days in a row last week. I'm on the motorcycle this week, it was feeling lonely. Rain, Blech! PM me if you want to go driving. Brent
  2. I'm running torsen and quite happy with the results. Couple of notes: 1. Given good traction on both tires, nothing beats an open diff. It has the fewest faults and the best power distribution characteristics of any configuration. 2. Another advantage of an open diff is that you don't completely loose cornering traction on the rear of your car just because you applied too much power. 3. Most torsen setups do have a limit on how much actual power they can handle. The good news is that those power limits usually assume a car that weighs at least twice that of an average 7. 4. There are different types of torsen that have more or less pre-load. I.E. Not all torsen's fail to transfer power when one tire has 0 traction. 5. A realy good traction control system that applies braking power to the spinning wheel can give you all the fantastic benefits of and open diff with all the traction of a torsen. But I think a system like that kind of misses the point of a 7 type car.... http://www.usa7s.com/aspnetforum/images/emoticons/lol.gif
  3. Florida... That's the origional #00 stalker with a 3.4 engine. Plenty more Stalker Vids Here: http://tinyurl.com/3d7up2 Brent
  4. Actually that was an excellent article. Very good research. However, It misses two important parts of the equation. The first part of the equation is area under the curve. The second part is driveability. Both of these are more a function of torque than a function of horsepower. Car engines don't have the luxury of always operating at peak horsepower. Like it or not, they are required to accelerate, slow down, stop, and otherwise work within a fixed set of 3 to 6 gears. Quite a number of real race car transmissions only have 2 gears. The first part, area under the curve takes into account the ability of the motor to work within the gear set that it has. It will only be near peak horsepower for a few hundred RPM. Therefore it is vitally important how the engine behaves when it is not at peak horsepower. A big broad torque curve helps the car accelerate over its entire RPM range not just for the few feet that it is near its optimum. Example: Autocrossing - I can come out of a fairly tight corner in third at around 2k rpm. At that point I can generate around 160ft lbs of torque at WOT (60hp). I can then accelerate so hard that I have to feather the throttle in order to keep the tires hooked up. (i.e. I am generating more rear wheel torque than the car can effectively use) I accelerate all the way to the next corner where I arrive still in 3rd at around 6k rpm and around 160ft lbs of torque (180hp). Along the way, I passed my peak horsepower at around 5500 rpm where I was generating almost 200 ft lbs of torque (209hp). With that big flat torque curve, I was able to accelerate almost as hard as my maximum all the way from 2k to 6k and didn't have to shift once. This is closely related to driveability. I have driven a couple of cars that technically had a cubic shitload of horsepower between 7k and 8k rpm. But trying to get them rolling from a stop sign just sucked. Slip the clutch, kill the motor. Slip the clutch more, burn the clutch. Launch and let the tires take the abuse and get a ticket from the local cops. Take it to the track and it can be just as bad. Below the power band, the accelerator pedal is nothing more than a wish list. In the peak power band you are fine until you have to use the throttle with finesse, then it behaves like an on/off switch. Too much, oops throttle oversteer, too little, oops trailing oversteer. "Dang that thing sure is twitchy!" So, to answer your article: Yes, you are absolutely correct. Horsepower rules. But, As a single tuning goal it only pays off at drag strips, Bonneville, and some long road races. However, most tracks, all autocross, and all street driving, it is far more important to have an engine that has a broad flat torque curve that is easy to manage. This lets you power out of a tight corner near the bottom of your rpm range, blast down the straight to the next corner, dive in and do it again. Now that's what I call fun! http://www.usa7s.com/aspnetforum/images/emoticons/coolgleamA.gif Brent
  5. Hi, I too own a Stalker. Chassis #20. I started exactly the same way you did... I think the tendency comes with the same gene that has us building our own cars in the first place. http://www.usa7s.com/aspnetforum/images/emoticons/coolgleamA.gif I called, I talked, I sent my down payment, I started searching for parts 6 months before I went to get the kit. Then I got the kit and everything changed. Suddenly I found that I didn't want to use the cheap, secondhand parts that I had sourced earlier. I wanted to put quality parts into the build because suddenly it mattered a lot to me. I still used a few of the parts I had found earlier, but I wouln't do it that way again. I'd wait and see how I feel about it after I start building the car. All I can say is call Dennis, he is a great talker, a genuinely nice guy and very knowledgeable. He has put a lot of time into designing the kits he sells. All the components work extremely well together. The build is very straightforward. And, the car, once you are done with it, will be everything you hope it to be. Brent
  6. Jack, You spoiled the surprise... http://www.usa7s.com/aspnetforum/images/emoticons/seeya.gif I hope all is well for you and your family. Brent
  7. Wow was yesterday a FANTASTIC day for a drive in the country, for Minnesota anyway. Probably one of the most beautiful days of the year...even if it is one of the last beautiful days of the year... Photos: http://66.41.218.133//oddfellows/oct2006.html Felin, I'm looking forward to seeing you on 7/7! A party to celebrate Both cars on the road! http://www.usa7s.com/aspnetforum/images/emoticons/hurray.gif Woo Hoo! Brent StalkerV6 #20
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