Does it hurt the car to rev to 5 rpm when starting from a stop and then taking foot off clutch?
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Does it hurt the car to rev to 5 rpm when starting from a stop and then taking foot off clutch?
There's soooo much power when that happens its unbelievable. Is this because the turbo has kicked in even before the word go?
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Other than the clutch...which is a cheap part...be concerned about the drivleline and awd
taking a massive beating... if you do it enough and you are using very sticky tire...ie the tire just grip with zero spin than think about where you are transferring all that torque to.... cheap luanches to 3-3500 rpm unless its raining...less chance of blowing somehting...
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It depends.
Basically, the issue is shock loads to the driveline.
If you dump the clutch with the engine at high rpm, the rotational energy stored in the flywheel is transferred to the driveline very quickly. Depending on how firmly the clutch engages, this can deliver torque values far in excess of what the engine can deliver on its own. Redlining the engine and dumping the clutch is a pretty standard technique for road racing starts in small-bore cars (i.e., rolling starts a la SCCA) but in a race car you have either already dealt with any driveline strength issues or you will soon have the opportunity. The limiting factor is when you spin the tires, which is not a good thing as the coefficient of friction drops dramatically. I would not do this in a street car.
If you release the clutch slowly -- maybe over a second or two -- and do not shock load the driveline then you are going to be o.k. Basically, you are just holding the engine and the turbo at higher rpm (= higher torque) for a quicker launch. Torque loads should remain within design limits. And, yes, it is harder on the clutch than a less aggressive start.
If you dump the clutch with the engine at high rpm, the rotational energy stored in the flywheel is transferred to the driveline very quickly. Depending on how firmly the clutch engages, this can deliver torque values far in excess of what the engine can deliver on its own. Redlining the engine and dumping the clutch is a pretty standard technique for road racing starts in small-bore cars (i.e., rolling starts a la SCCA) but in a race car you have either already dealt with any driveline strength issues or you will soon have the opportunity. The limiting factor is when you spin the tires, which is not a good thing as the coefficient of friction drops dramatically. I would not do this in a street car.
If you release the clutch slowly -- maybe over a second or two -- and do not shock load the driveline then you are going to be o.k. Basically, you are just holding the engine and the turbo at higher rpm (= higher torque) for a quicker launch. Torque loads should remain within design limits. And, yes, it is harder on the clutch than a less aggressive start.
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