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Old 06-11-2006, 02:05 AM   #10
bambam89lx
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Re: How to build a "RELIABLE" lsvtec/b20vtec guide.

Quote:
Originally Posted by anthony90si
i assume the difference with a turbo is in the power band! thats why they need soo much more hp to run the same?
please, let's keep this thread to vtec related questions. I will answer your question though.
When you hear of turbo power, the power stated is the "peak power". All motor cars have more of a flat torque courve, rather than a climbing and peaking one.
Here are some other general reasons:
turbo cars spin tires easier, because of the instant surge of power. Generally, all motor cars don't spin tires at all.
turbo cars have to "climb" to their power level...it isn't instant power, whereas an allmotor setup is.
The higher your peak power is, the better. Usually, all motor setups are built to where there peak power is in the 9-10k range. This is an advantage, because the faster the motor spins, the faster the tires spin, and therefore, faster the car accelerates and moves. Turbo cars usually peak in power, earlier in the power band, and then have a sudden drop off, which is terrible for drag racing. It's not about how much peak power you make at all...it's about where that peak power is in the power band. It's more about how fast you can get the car to accelerate. That is the MAIN goal. You don't need as much power at higher rpms because even if you aren't making alot of power up there, you are still accelerating faster than a car that is making higher peak power 3k rpms sooner (allmotor vs. turbo). Think about it, he may have more power, but your are still spinning your tires 3000 more times than his, every minute(if he shifts at 7k and you shift at 10k)...so you will travel further than him, which means you will accelerate faster.
Get it?
If you could build a turbo honda motor that would make peak power at 9500 rpms, had a steady climb up to that power level, and had a relatively flat torque curve, you'd be all set. But, it's near impossible, because to make power that high, requires an incredibly large turbo, which lends to low end power (turbo lag), tire slipping, bad torque curves, etc...which lead to shitty quarter mile times. That is the whole reason it takes alot more power with a turbo setup to run the same times as an allmotor setup, to negate the whole lag, spinning, torque curve problem.

This is essentially the only reason we can even build cars to keep up with v8's. They usually make incredible torque and HP at 3-4k rpms and just fall off. If they could build a v8 motor that could peak power at 8-9k, it would be over for us import enthusiasts. But, that will never happen without ALOT of money. The v8 design puts alot of stress on the lower end, which prevents them from ever spinning it that high. That is the sole advantage of inline motors. That's why inline motors are king, motors like the skyline, supra. And, also why rotaries are so good for racing...they don't need to make alot of power, because they can rev so god daym high.
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