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mtch · 06-24-2006, 08:32 PM

[QUOTE=986Jim]

Highest peak HP wins. It doesn't matter if it makes it over a wider range or not. Accelerations is one thing, you can math that to death, but the motors ability to accelerate or rev in a gear is a whole other story. The second car has higher peak power but less power overall will be faster. You simply can NOT argue this, it's a proven fact, goto a drag racing forum and ask, they will math you to death.

Even in the car with 250whp over a steady range will still want to shift at the highest absolute RPM point even if power is dropping off at that point, it will still be faster.

It's not about the most power across a band, is ONLY about the most power. Stop using math, and goto the race track and see what happens. Cars with big long flat power bands can get beaten by cars with lots of peak HP, because thats what wins races.
QUOTE]

You seem to disregard the theoretical explanations, so I have a few real world experiences for you. My two previous cars were a LT-1 Z28 and a highly modified Acura RXS-s.

The Z-28 made gobs of tq but couldn't breath up high. I ran better times short shifting instead of holding to readline. Additionally, I frequently raced a local guy who had a NSX. His car made about 17 more whp than mine, but my tq numbers were much higher (about 75) and power curve much flatter. The race was a driver's race, he won some and I won some, but according to your experiences, his car should have beat mine each time, especially since his car was lighter.
His trap was higher and if we raced farther, he would eventually walk away, but you see how this situation counters your statement.

My Acura RSX-s made 174 hp and 140 ft-lbs at the wheels when stock. After modifications it made 213 whp but tq ony increased by 3 ft-lbs. I currently own a Cooper-S used for daily dutuies, which makes 183 hp and 176 ft-lbs at the wheels. The cars have identical 1/4 times. The trap speed of the Acura is higher and on the highway at higher speeds, the higher reving higher hp engine wins, but in auto-x and in the 1/8 and 1/4, the broader power band and responsiveness mades up for the lower peak power.

The power band is more important than peak power, and for someone who spends time at the track I'm surprised you don't see this. How many 700-800 hp Supras-MKIVs have you seen run slower than 500-600 hp ones. In order to make this much power, the twin turbo is swapped for a single larger one. It makes big power, but takes so long to spool up ( which means a peaky power curve ) that it's too late by the time is really kicks in. The lower hp cars use twin (actually sequential) turbos, which means power from low to high (flatter curve). I have two co-workers with Supras i described above, 550hp vs 920 hp and the lower hp usualy wins. This is also true for the Suby Sti. When modified to make more hp, they sacrifice a flat power band, which means they lose the hole shot and play catch up the rest of the race. This is a fairly common occurance to see at the tracks.
This should clearly illustrate that peak hp does not win races, in wins braggin rights.

06-24-2006, 08:32 PM	#54
mtch Registered User Join Date: Sep 2005 Location: TN Posts: 83	[QUOTE=986Jim] Highest peak HP wins. It doesn't matter if it makes it over a wider range or not. Accelerations is one thing, you can math that to death, but the motors ability to accelerate or rev in a gear is a whole other story. The second car has higher peak power but less power overall will be faster. You simply can NOT argue this, it's a proven fact, goto a drag racing forum and ask, they will math you to death. Even in the car with 250whp over a steady range will still want to shift at the highest absolute RPM point even if power is dropping off at that point, it will still be faster. It's not about the most power across a band, is ONLY about the most power. Stop using math, and goto the race track and see what happens. Cars with big long flat power bands can get beaten by cars with lots of peak HP, because thats what wins races. QUOTE] You seem to disregard the theoretical explanations, so I have a few real world experiences for you. My two previous cars were a LT-1 Z28 and a highly modified Acura RXS-s. The Z-28 made gobs of tq but couldn't breath up high. I ran better times short shifting instead of holding to readline. Additionally, I frequently raced a local guy who had a NSX. His car made about 17 more whp than mine, but my tq numbers were much higher (about 75) and power curve much flatter. The race was a driver's race, he won some and I won some, but according to your experiences, his car should have beat mine each time, especially since his car was lighter. His trap was higher and if we raced farther, he would eventually walk away, but you see how this situation counters your statement. My Acura RSX-s made 174 hp and 140 ft-lbs at the wheels when stock. After modifications it made 213 whp but tq ony increased by 3 ft-lbs. I currently own a Cooper-S used for daily dutuies, which makes 183 hp and 176 ft-lbs at the wheels. The cars have identical 1/4 times. The trap speed of the Acura is higher and on the highway at higher speeds, the higher reving higher hp engine wins, but in auto-x and in the 1/8 and 1/4, the broader power band and responsiveness mades up for the lower peak power. The power band is more important than peak power, and for someone who spends time at the track I'm surprised you don't see this. How many 700-800 hp Supras-MKIVs have you seen run slower than 500-600 hp ones. In order to make this much power, the twin turbo is swapped for a single larger one. It makes big power, but takes so long to spool up ( which means a peaky power curve ) that it's too late by the time is really kicks in. The lower hp cars use twin (actually sequential) turbos, which means power from low to high (flatter curve). I have two co-workers with Supras i described above, 550hp vs 920 hp and the lower hp usualy wins. This is also true for the Suby Sti. When modified to make more hp, they sacrifice a flat power band, which means they lose the hole shot and play catch up the rest of the race. This is a fairly common occurance to see at the tracks. This should clearly illustrate that peak hp does not win races, in wins braggin rights.