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I might be wrong about this, but shouldn’t the manual have more rwhp than automatic? I have heard that a lot of power loss occurs in the torque converter, which is eliminated in the manual transmission configuration. Thus we have faster 0-60 times for manual, right? So, 215 hp is at the crank than. What’s the hp at the wheels than, and wouldn’t manual have a better rwhp than automatic?

Sorry, keep repeating my question…

Thanks.

G.
 

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it is true that manuals have less drivetrain loss than automatics...however - i dont know how much the rwhp will be because i dont knwo how much loss there is in the 5 speed we are getting - if anyone does know - post it because i would also like to know
 

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Good question! What about gear ratios, does that have any effect on calculating RW hp? I think the manual has higher gear ratios, for better gas mileage - maybe that's why the hp rating is the same? It seems like there's no way they'd have the same HP unless the manual was detuned - or maybe it IS higher hp, they just don't publish it.
 

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well - the HP they claim is to the flywheel - 215/218(hp/trq) the engine does put this much out
however - once going through the drivetrain there is loss - the automatics range between 160-170 rwhp....the manual should provide less mechanical loss, but the question is: how much??
 

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Right, yet Lexus is posting 215 hp for the manual, which would imply it has just as much loss as the auto. Most cars have the same rating in fact. Maybe carmakers just under report the manual HP, so automatic buyers don't feel shortchanged.


Originally posted by scoot557:
well - the HP they claim is to the flywheel - 215/218(hp/trq) the engine does put this much out
however - once going through the drivetrain there is loss - the automatics range between 160-170 rwhp....the manual should provide less mechanical loss, but the question is: how much??
 

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ok - maybe im a little confused...this is how i understood it....correct me if im wrong
however - the 3.0 I6 2JZ-GE puts out 215/218(BHP/TRQ) regardless of the transmission....when coupled with an automatic, the rwhp is about 160-170, when coupled with a manual transmission, there will be less drivetrain loss so the rwhp will be >170, but i dont know by how much.
i always thought the published HP was the rating of the engine BHP, not the rwhp....hence the published HP for both auto.manual package would be the same because they are doing BHP not rwhp??? and gear ratios shouldn't effect HP - just things like acceleration/top speed/gas mileage....am i confused or do i have a handle - because now im confusing myself
 

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You're getting the hang of it scoot557, the HP is measured at the flywheel, which is before the tranny in either case, pretend there were no tranny at all all and thats how they measured it, not at the rear wheels.
The tranny and gear selections are what will make the difference in RWHP NOT HP AT THE FLYWHEEL, the engines are the same, since the manuals are a direct connection with the engine, they are more effcient, rather than an auto that is essentially driven through oil in the TC.

In most common cases, a manual will have about 15-20% loss in power, while an auto has somewhere around 20-25%, (25% for the really crappy cars out there).

I think the IS auto tranny has a 18-23% loss or something from what I've heard people dyno.
 
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