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Old 01-04-2013, 07:45 PM   #66
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Originally Posted by turbosvtfocus04 View Post
Smaller turbos will result in more torque, bigger turbos not as much. We will take a dodge srt4 for an example, makes 310whp 454wtq. But as soon as you go bigger turbo and add cams torque isn't as high, 420whp 380wtq. Rpms got pushed up bc of the slightly bigger cams which is a result in torque loss, you can also lose low end torque by switching intake manifolds as well.

And as for you to say 2.3 turbo could make more power, till you hit a certain amount of hp or big enough turbo then the 2.0 will make more due to it being able to rev higher and also bigger strong since the piston pin isn't moved up on the piston. And yes I have seen this happen when stroking a motor where the piston pin was too high on a motor with a turbo.
I'm not sure if he understands that horsepower is just a function of torque. If torque is constant then the only way to get more HP is to rev higher. If torque is not constant but large at the beginning and tapers off then the HP will raise and plateau. If the torque starts low and then jumps at the upper ranges then you have no HP at all until the torque jump which at that point becomes ridiculous.

I imagine the second SRT example was due to the cams having more overlap. A small turbo will spool quickly and run out of breath. A large one will take forever to spool and then become a monster.

An ideal NA motor has a flat torque curve which will yield a perfectly diagonal HP curve up to redline, i.e. a rotory.

Interesting debate but how much have we helped the OP?
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