LoUsyGamER
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Tldr: your tyre, rims and even brakes affect your long term spending.
Recently, I was surfing the web and came across multiple dyno tests for car. There are those on rollers and without wheels. I came to notice, despite which shops doing ecu remap, the gain is usually the same, plus minus a bit. Interesting, the dyno on rollers (with wheels) and dyno without wheels gains around the same hp. Thus, the drivetrain loss is fixed for ecu remap instead of percentage.
What is drivetrain loss? When manufacturer sells car with horsepower (eg 100hp) stated, that 100hp is determine at the crank/engine, aka chp (crank hp). However, the power after going through the gearbox, axle, wheels and etc, the wheel (touches the road) had a much lower hp, aka whp (wheel hp). Awd will loss more hp than fwd/rwd, automatic losses more hp than manual. Let's take a awd car as example, assuming the chp is 100hp, if it losses 30% due to drivetrain, the whp is 70hp. While a fwd car might only loss 20%, the whp is 80%. That is why awd cars are more thirsty than fwd cars, assuming the same car model.
Based on research and forums, the drivetrain losses about 50% are due to tyres, rims and brakes. The loss ratio of tyres: rims: brakes is estimated to be 1: 1.5: 2. So for drivetrain loss due to weight gain by the tyres, it is 2 times the drivetrain loss due to weight gain of the brake.
Nowadays people like to change rims, bbk which also affect the tyres. Bigger and wider rims, bigger brake more cool. The bigger and wider the rims, the likelihood the rims and the fitted tyres are much heavier. If from 17 rims to 19 or even 20 inch rims, it could weight double the original size. Thus, the drivetrain loss jumps.
For sport car, high power:weigh ratio, every 0.5kg gain at wheels (tyre and rims) losses around 1 whp, losing 0.5kg gains around 1whp. For most bnb cars, every 0.5kg gain at wheels losses around 0.3whp, 0.5kg loss gain around 0.3whp. However losing wheels weight has diminishing effect on drivetrain loss after a certain weight loss.
With more drivetrain loss, the car will need to stress more to reach the same speed compared to a lighter wheels, petrol burns faster and brake slower.
When next time you want to change rims or even just change tyres, go for something light, your car feels lighter, more agile, more reactive to your brake (better than bbk in Sg context and non-track) and you will visit petrol kiosk less often.
Stock is the best.
Recently, I was surfing the web and came across multiple dyno tests for car. There are those on rollers and without wheels. I came to notice, despite which shops doing ecu remap, the gain is usually the same, plus minus a bit. Interesting, the dyno on rollers (with wheels) and dyno without wheels gains around the same hp. Thus, the drivetrain loss is fixed for ecu remap instead of percentage.
What is drivetrain loss? When manufacturer sells car with horsepower (eg 100hp) stated, that 100hp is determine at the crank/engine, aka chp (crank hp). However, the power after going through the gearbox, axle, wheels and etc, the wheel (touches the road) had a much lower hp, aka whp (wheel hp). Awd will loss more hp than fwd/rwd, automatic losses more hp than manual. Let's take a awd car as example, assuming the chp is 100hp, if it losses 30% due to drivetrain, the whp is 70hp. While a fwd car might only loss 20%, the whp is 80%. That is why awd cars are more thirsty than fwd cars, assuming the same car model.
Based on research and forums, the drivetrain losses about 50% are due to tyres, rims and brakes. The loss ratio of tyres: rims: brakes is estimated to be 1: 1.5: 2. So for drivetrain loss due to weight gain by the tyres, it is 2 times the drivetrain loss due to weight gain of the brake.
Nowadays people like to change rims, bbk which also affect the tyres. Bigger and wider rims, bigger brake more cool. The bigger and wider the rims, the likelihood the rims and the fitted tyres are much heavier. If from 17 rims to 19 or even 20 inch rims, it could weight double the original size. Thus, the drivetrain loss jumps.
For sport car, high power:weigh ratio, every 0.5kg gain at wheels (tyre and rims) losses around 1 whp, losing 0.5kg gains around 1whp. For most bnb cars, every 0.5kg gain at wheels losses around 0.3whp, 0.5kg loss gain around 0.3whp. However losing wheels weight has diminishing effect on drivetrain loss after a certain weight loss.
With more drivetrain loss, the car will need to stress more to reach the same speed compared to a lighter wheels, petrol burns faster and brake slower.
When next time you want to change rims or even just change tyres, go for something light, your car feels lighter, more agile, more reactive to your brake (better than bbk in Sg context and non-track) and you will visit petrol kiosk less often.
Stock is the best.
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