Stock Dyno and "After Mod Dyno"
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From: LA
Stock Dyno and "After Mod Dyno"
So let's say G35 stock has "240 HP" and "200.8 Torgue" on Dyno,
I am going to Mod the Stillen Exhaust(From header to Cat~)
and I will Mod the 4 puleys also
Where the HP will go to?
What do you guys think?
or anyone Moded the same thing, and had the result already?
I am going to Mod the Stillen Exhaust(From header to Cat~)
and I will Mod the 4 puleys also
Where the HP will go to?
What do you guys think?
or anyone Moded the same thing, and had the result already?
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Joined: Jul 2005
Posts: 1,090
Likes: 1
First off forget HP. Focus on torque. Peak HP numbers are meaningless except that they can help to sell cars. If you want better performance on the street, focus on improving your engine's torque over the 2K to redline rev range. Keep in mind that what makes you car accelerate faster is a function of two factors: engine torque output and gearing. This will determine how much torque you get to the drive wheels, and ultimately how fast you will run the 1/4.
Let me give you a hypothetical example to illustrate my point. Let's say this hypothetical car produced 125 lb/ft of torque at 2K rpm and then the torque increased by 10 lb/ft every 500 rpm until it maxed out at 185 lb/ft at 5 K rpm. Let's say that in 1st gear the gear ratio was 3.5, and the car redlined at 6500 rpm. In order to calculate the torque to the drive wheels you multiply the engine torque output by the gear ratio. So at 2K rpm you'd have 125 X 3.5 or 437 lb/ft of torque at the drive wheels, and so on until you maxed out at 185 X 3.5 at 5K rpm. So would it better to add a mod that gave you a 10% increase in torque over that entire rev range than another mod that gave you 20% but only kicked in at 5K rpm?
My example also gives you an idea of why a car like a Porsche 997S with 295 lb/ft of max engine torque output has a faster 1/4 time than a Corvette C6 which has 400 lb/ft of max engine torque. Since both cars have approximately the same curb weight, you'd expect the C6 to be much faster but in reality the 997S is about a half sec faster in the 1/4. The reason is torque over the rev range and gearing.
Let me give you a hypothetical example to illustrate my point. Let's say this hypothetical car produced 125 lb/ft of torque at 2K rpm and then the torque increased by 10 lb/ft every 500 rpm until it maxed out at 185 lb/ft at 5 K rpm. Let's say that in 1st gear the gear ratio was 3.5, and the car redlined at 6500 rpm. In order to calculate the torque to the drive wheels you multiply the engine torque output by the gear ratio. So at 2K rpm you'd have 125 X 3.5 or 437 lb/ft of torque at the drive wheels, and so on until you maxed out at 185 X 3.5 at 5K rpm. So would it better to add a mod that gave you a 10% increase in torque over that entire rev range than another mod that gave you 20% but only kicked in at 5K rpm?
My example also gives you an idea of why a car like a Porsche 997S with 295 lb/ft of max engine torque output has a faster 1/4 time than a Corvette C6 which has 400 lb/ft of max engine torque. Since both cars have approximately the same curb weight, you'd expect the C6 to be much faster but in reality the 997S is about a half sec faster in the 1/4. The reason is torque over the rev range and gearing.
Originally Posted by FAST1
First off forget HP. Focus on torque. Peak HP numbers are meaningless except that they can help to sell cars. If you want better performance on the street, focus on improving your engine's torque over the 2K to redline rev range. Keep in mind that what makes you car accelerate faster is a function of two factors: engine torque output and gearing. This will determine how much torque you get to the drive wheels, and ultimately how fast you will run the 1/4.
Let me give you a hypothetical example to illustrate my point. Let's say this hypothetical car produced 125 lb/ft of torque at 2K rpm and then the torque increased by 10 lb/ft every 500 rpm until it maxed out at 185 lb/ft at 5 K rpm. Let's say that in 1st gear the gear ratio was 3.5, and the car redlined at 6500 rpm. In order to calculate the torque to the drive wheels you multiply the engine torque output by the gear ratio. So at 2K rpm you'd have 125 X 3.5 or 437 lb/ft of torque at the drive wheels, and so on until you maxed out at 185 X 3.5 at 5K rpm. So would it better to add a mod that gave you a 10% increase in torque over that entire rev range than another mod that gave you 20% but only kicked in at 5K rpm?
My example also gives you an idea of why a car like a Porsche 997S with 295 lb/ft of max engine torque output has a faster 1/4 time than a Corvette C6 which has 400 lb/ft of max engine torque. Since both cars have approximately the same curb weight, you'd expect the C6 to be much faster but in reality the 997S is about a half sec faster in the 1/4. The reason is torque over the rev range and gearing.
Let me give you a hypothetical example to illustrate my point. Let's say this hypothetical car produced 125 lb/ft of torque at 2K rpm and then the torque increased by 10 lb/ft every 500 rpm until it maxed out at 185 lb/ft at 5 K rpm. Let's say that in 1st gear the gear ratio was 3.5, and the car redlined at 6500 rpm. In order to calculate the torque to the drive wheels you multiply the engine torque output by the gear ratio. So at 2K rpm you'd have 125 X 3.5 or 437 lb/ft of torque at the drive wheels, and so on until you maxed out at 185 X 3.5 at 5K rpm. So would it better to add a mod that gave you a 10% increase in torque over that entire rev range than another mod that gave you 20% but only kicked in at 5K rpm?
My example also gives you an idea of why a car like a Porsche 997S with 295 lb/ft of max engine torque output has a faster 1/4 time than a Corvette C6 which has 400 lb/ft of max engine torque. Since both cars have approximately the same curb weight, you'd expect the C6 to be much faster but in reality the 997S is about a half sec faster in the 1/4. The reason is torque over the rev range and gearing.
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