IMO, there's something that we haven't take into account about "exiting corners".

Even if you are able to exit with proper rpm/gear, your turbo will still have lag. Between the moment when you punch the throttle and the moment when the car gives full tq (boost) there will be some delay, always. And the GT3 in front will take a little advantage.

Anyway, a good driver who knows his car and how to make it go fast through the corners, will have no problems fighting with a N/A car and eventually kill it.

This is, in my opinion, a very good driver, for example.

http://www.youtube.com/watch?v=B64wy7MLhlw


This is a 6speed member, and the car in the video had k24,ICs,dv,5 bar and tune.

(now has 18gs...)

 

I was always under the impression that a broader power band is better than a peak power band for track cars. Peak power bands are great for drag racing, but you want a fat power band for track cars. Otherwise the difference between low boost and high boost is like a light switch that will put you in the wall. So a K16 hybrid should be better for tracking than a K24 hybrid just because of the fatter torque curve. The K24 hybrid should be better for drag racing because of the higher flow up top. But for the K24 hybrid to take advantage of this it needs the higher redline associated with built engines.

 

(I haven't read the whole thread, and I apologize if I'm repeating anything... )

First, torque does not necessarily fall off at 5250. In fact, it very frequently falls off well before 5250 in street engines, and well after that on race engines. There are an increasing number of street cars that come with torque peaks at 7k or more. The 5250 number is not a magical rule of physics where all torque curves drop off. It's just a single parameter of the HP equation, and mathematically the torque and HP numbers cross at that point. In other words, it's a pretty arbitrary number.

The simplest summary of TQ vs HP is that torque is a unit of force, and HP is the measure of how many times you can apply that force in a given period of time. Without motion (RPM), TQ is worthless because there is no work being done (HP). At one extreme, you can have 1000 lbs ft ot TQ, but unless there is some RPM (motion), you still have 0 HP. In other words, no work is being done even though there is tremendous torque. At the other end, let's say you have 1 lbs ft of TQ, but the engine is spinning at 100000 RPM. Because that small amount of work is being done 1000s of times per second, you actually have an incredible amount of work, and thus lots of HP. Think F1 engine.

Then there's gearing. Gears are used as force (TQ) multipliers. Your car accelerates faster in 1st gear than 2nd due to the fact the the available TQ is multiplied more in 1st due to the lower gear ratio.

See the attached spreadsheet for some interesting numbers. It has old data for my race miata, but if you plug your torque curve numbers (from a dyno chart), rear tire size, and gear ratios into the yellow boxes on the first tab, you'll be able to chart the actual force at the wheels in the various gears and speeds on the second tab. Yes, there really are thousands of lbs ft or TQ being applied to the rear wheels in the lower gears! This chart can also be used to easily determine optimal shift points. Look at the force curves for each gear. When the curve for the lower gear falls below that of the next higher gear, you'll want to short-shift around that point. You can determine the RPM by drawing a vertical line from the point at which the curves cross. Take that line up to the straight RPM lines that run at an angle up and to the right for each gear. It may be a little confusing, but I didn't really design this spreadsheet for public consumption. Also note that if the force curves don't cross, then shift at the rev limit for max acceleration. There's some additional interesting information in the first tab, like the theoretical acceleration (in G) at various speeds in each gear.