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gears and the ole VTEC?

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Old Jan 3, 2011 | 08:58 AM
  #21  
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I apologize for the "head out of the clouds" statement. Too many beers ...

If you plot actual torque to the wheels by speed for a stock AP2 and an AP1 with 4.77 gears, you'll see that they are almost identical for the 1st 4 gears. The difference in secondary reduction gears combined with the difference in torque and difference in rev limits all work out to be about the same. So if you then swap out the 4.1 gears on an AP2, it will be about like an AP1 with 5.16 gears!

Regarding VTEC engagement, the rise in torque after 3500 RPMs is due to VTEC engagement. If it didn't engage at 3500 RPMs, the torque would have dipped down until it engaged. The second increase in torque at 5500 RPMs is just from the "sweet spot" in the intake and exhaust tuning. A different intake, cam, header, and / or exhaust would change the location, amplitude, and width of that sweet spot, and also the optimum VTEC engagement point. With my T1R header, VTEC engagement needs to be a few hundred RPMs higher. When I swapped out my stock intake with a PWJDM intake, the torque curve went from having 3 smaller humps to having 2 larger humps.
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Old Jan 3, 2011 | 02:46 PM
  #22  
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Originally Posted by gernby,Jan 3 2011, 09:58 AM
I apologize for the "head out of the clouds" statement. Too many beers ...
No problem!...maybe if I had a few I wouldn't
be sooo sensitive!

Thanks for the input from you and ans2k...I won't be
considering 4.3 anymore...just can't justify the cost for
such a small gain...but I had to consider the advice from
someone who's such a gear expert.

I will still consider the 4.44...in my thought process..which
might be skewed...I have to think adjusting gearing like this
is akin to reducing vehicle weight....and even though it's a change
from OEM..it still just takes advantage of the free-revving nature
of this engine.

I have to admit gernby...I'm goig to talk to some tuners to see what
it will take to get a dyno like your's....that's all I want is the low end
grunt you have and be it gears or tuning/bolt-ons I don't care as long
as I get my desired performance.
I'm finally maybe understanding...Ive been staying away from anything
that will lower VTEC thinking that it will be like OEM VTEC when in fact
I think it's a much smoother transition.
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Old Jan 3, 2011 | 03:39 PM
  #23  
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Originally Posted by buzzin hornet,Jan 3 2011, 06:46 PM
I will still consider the 4.44...in my thought process..which
might be skewed...I have to think adjusting gearing like this
is akin to reducing vehicle weight....


This is why I'm so insistent. You REALLY need to understand the tradeoffs of gears. Weight reduction is a Win - Win, but gear swaps are a Win-Lose (or Lose-Win). If you're a drag racer, and are NA, then 4.77's will kick ass for you. However, if you're an autocrosser, or have an SC, then you'll absolutely HATE 4.77's. If you're a street racer (hopefully not) who does rolling start drag races, then you'll probably start losing more races with 4.77's.

Gear swaps are a CHANGE in performance, not a GAIN in performance.

EDIT: the reason why I mention 4.77's is because they are the extreme. You'll run into the same issues with 4.44's, just not as often. I'm personally considering finding an AP1 owner who would swap secondary reduction gears with me so that I can have the equivalent of 3.90 gears to be more competitive at autocrossing.
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Old Jan 3, 2011 | 03:46 PM
  #24  
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Go 4.44 for daily driving/track usage. Awesome final drive gears for AP1 or AP2. It will give you the low-end grunt you want and make 1st through 4th gears a lot more fun. It decreases highway mileage a tiny bit but you'll probably gain 2-3 mpg in the city thanks to less load n the engine.

If you've ever driven an RSX-S, the 02-04 has a 4.4~ final drive and the 05-06 has a 4.7. Stock they make less power than an S2000 but feel like they have a lot more low end grunt. Their final drive gears are why.

Going off the deep end, I think I even read somewhere that 4.44, 4.57 and 4.77 gears are like adding 25-30 lb ft of torque to the S2000. Would be interesting to see an accurate calculation.
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Old Jan 4, 2011 | 03:01 PM
  #25  
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Originally Posted by gernby,Jan 3 2011, 04:39 PM


This is why I'm so insistent. You REALLY need to understand the tradeoffs of gears. Weight reduction is a Win - Win, but gear swaps are a Win-Lose (or Lose-Win).
Hope I didn't frustrate you too much!

I had questions....I asked...and you and others answered them
quite well for me!

Sure....I didn't come off as being the smartest S2k poster....
in the end I win by being able to make a better decision.

Thank you as well disguspated...I will never autocross/track or
drag race....and while I LOVE the stock '06..above 4K...I'm
just looking to improve my 1/4 time...or heck..just 0-50.

Still going to talk to some tuners....but right now leaning
towards 4.44.

thanks again
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