Modified exhaust - horsepower and torque

When the exhaust path is shortened, each corner is gradually smoothed to reduce exhaust resistance after the smoothness that is relatively higher. But the principle mentioned before , stubby type of exhaust pipe is suitable for high power output rotational speed , the elongated exhaust pipe is good at low speed torque output ; difference between the two phenomena cause principle is slim because the pressure inside the exhaust pipe high, medium and low speed to quickly exhaust discharged from the exhaust port , but a lot of exhaust gases at high rpm will face the disadvantage of blocking the exhaust pipe and the exhaust temperature is too high . By contrast, stubby exhaust pipe will have a low rpm exhaust the problem of slow, but to the high- speed region will be able to play the most exhaust unobstructed.(coilovers)
General production car exhaust pipe, exhaust stroke should be considered when selecting relatively straight exhaust pipe, and then the change in the diameter, so as to take into account the performance of the whole speed range. (volkswagen turbo)Modified community now more popular choice according to 10-15% in the middle of the exhaust pipe diameter to the original best, that is, naturally aspirated engine 52mm to about 60mm, 65mm turbo engine is about to 75mm. Of course, the greater the displacement of the engine , the larger the target power conversion then have a corresponding increase may also reach 80mm. Speaking allocation ratio of diameter from coarse to fine or the same caliber from start to finish , the need for attention to the torque owners will be more useful. If only the pursuit of performance, and that choice is gradually enlarged exhaust pipe is better, this amplification type exhaust pipe design is the use of slowly expanding the diameter of the way to make more back the more accelerated expansion of gas discharge , especially in the case of high- speed continuous effect will be more obvious, this approach is the choice of Japanese modified car more exhaust pipes.(coilovers)