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Old 09-24-2009, 06:43 PM   #28 (permalink)
ZCarMan
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Originally Posted by RCZ View Post
For you rookie guys, be careful when a manufacturer advertises 16hp versus 16 wheel hp (whp) They are far from the same thing. Unless you are talking to someone who is really in the know (to whom HP means WHP) then simply "hp" means break horsepower, or the actual horsepower that the ENGINE is producing. Remember that to get this "engine" horsepower down to the ground and move the car you have to transfer it through a series of gears (transmission) and then whatever manages not to get lost in the transmission has to make the wheels spin in order to thrust you forward. The more inertia the engine has to overcome, the less power will actually make it through, thats why 19" wheels will rob you of more power than the same exact wheel in its 18" variety. Now, because this is a rear wheel drive car instead of say, an all wheel drive car, the loss in the transmission may be as low as 8-15%. The transmission is much simpler than it would be on an AWD car which in the case of say, a Subaru WRX STI, can be as much as 20-23% of the engine HP. In fact Subaru advertises 300HP from the factory, while in reality, if measured on a dyno, the car only actually makes 220-235WHP stock. I have no idea how much WHP a stock 370Z will make, but most likely, following the 8-15% rule, it will make somewhere around 285-300 rear wheel HP. Most likely a lot closer to that 285rwhp number. I have no idea how much the G37's are making stock at the wheels, but I assume they will loose a bit more power than the 370Z will through their transmission as the Z has lighter, more focused materials such as that carbon fiber driveshaft. Another thing to take into account is that non-turbo (naturally aspirated or N/A) cars don't generally make that much power from these basic modifications. Mods such as intakes, will NOT, in reality get you much more than maybe a 5WHP gain. Exhausts will maybe free up another 10WHP, maybe 15-20WHP with good headers. You get the idea. The only real way to tell what your car is making is to actually test it, you cant just add up what the aftermarket manufacturers say you will get and then claim thats what you have. You cant just add up what other people are getting for WHP from these parts either. 5whp+10whp isnt going to be 15whp, may be less, may be more. (usually less on NA cars)

I do believe COBB, their accessport can do great things so I wouldnt be all that surprised to see a 16whp gain from their software. Stage 1 for them is just the software. Stage 2 is intake, exhaust and software. As expected, COBB stage 2 makes about 295-300WHP. Right on the money. SO can you feel 16WHP, probably just a little bit yeah if you are used to your car and know exactly what it feels like. Can you feel 30whp? definitely.

Dont get thrown off by those loud intakes which make it SOUND like you're going faster, while you may have even lost HP from a poorly designed intake.

Can anyone confirm how much WHP the G37 is making stock?



I agree with these number estimates. 320-330whp sounds about right without any major major work.

The thing is that some people aren't looking for huge numbers. I'm not saying you are or arent, my next comment isnt directed at you at all so dont get offended in any way please.

A lot of people like to slap TT's on their car so they can say they have X00rwhp and then make driveby videos on the highway to make sure everyone knows just how much power they have haha. After that they putt back to the city and park it at their favorite hang out. Every now and then they go to the quarter mile track and run 13's still because they cant get any power down. I'm not saying there's anything wrong with having a really fun car that can light them up in 4th though .

Other people, like me, are more concerned on whether the car can handle a full track day without melting and whether the torque curve makes you go faster everywhere and not just the straightaways. Don't get me wrong, if I could have a 500whp TT setup that doesnt overheat and has the response of an N/A car, I'd be all over it.

So all in all, while a TT setup would be cool, it may not be advisable for everyone. That would be why someone might be more interested in spending a little more money on other stuff instead of going FI. If youre looking for big power, response and reliability, then you will be spending a whole lot more money (normally) than otherwise. Not to mention that if you crack a ring or a rod with the extra stress from the turbos, then youre going to be looking at lots of $ just to fix the issue. It all depends on what you want the car to do and what your budget is.

Im pretty sure you already knew all that because of the other mods you suggested, so this isnt for you, its for the guys who are new at this. TT's aren't the fix all solve all solutions people sometimes make them out to be.
I'd just like to say thanks for all the knowledge you share with us. From my short time on this forum, you have consistently put out balanced and accurate information for the true race types to the every day fun in the sun driver of the 370Z. I've learned much from reading your posts and hope to learn even more in the following days. A huge BZ to you! Thanks.
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