Project G37S Transmission Upgrade part 2
The tuning from UpRev unlocked so much usable power in the low end below 3900 RPM, there’s over 36 lb/ft over our baseline. Big gobs of horsepower too (over 24 hp) that will be great for daily use.

With the new tune, Omar unlocked 36.1 TQ and  24.7 HP in the very usable 3000 RPM to 3800 RPM range.  The broad power gains continued up the rev curve with a very respectable 12 hp and 13 lb/ft.  Maximum HP reading was 264.2 HP at 7180 RPM which is 11.3 more HP and 215 lb/ft at 5280 RPM or 13.2 TQ more than our baseline.  While our Superflow reads low these are really impressive gains across the RPM range and a testament to the tuning expertise at UpRev.

Don’t worry these shots look faster than they were. We got ‘off road’ for any real full throttle runs. The car drives so much better than before it really has been transformed from soft GT cruiser to performance machine.

At last, we got the car out for a little bit of a shakedown and the power delivery was amazing.  What can be best described as the engagement grip of the transmission to the engine is radically different.  The car feels fast, accelerates fast, shifts fast.  It is like a new car, only better and ready to handle a lot more power.  It’s actually fun to shift the car in manual mode now where the torque converter locks up 100% and shift through the gears. Gear changes are crisp and immediate and really shove the car forward.  This new transmission along with all the other parts we’ve added to date truly make this car feel special and unlike its roots of being a mass produced luxury GT cruiser. When we first spoke to Pat at Level 10 he said we’d really love the way the car shifted and after installing his transmission and driving it, he was right.





  1. Surprised there is no love for this. I totaled my G37S at a track day and it still bums me out. But the transmission was a very weak link. I imagine this upgrade would really wake it up. How is the transmission for daily driving?

  2. Daily driving is almost like stock. There’s definitely a difference when the transmission is cold versus warm; best described as a small stumble that happens between gear changes. Once warm though this completely goes away. When decelerating and the car downshifts the engine braking is definitely more pronounced. Not to repeat what was already put in the article but gear changes now really shove the car forward where before shifts really felt soggy. None of this takes away from the car it only adds to the grins and this upgrade appears to be a must for forced induction.

    I’m sorry to read about your car. Hopefully your replacement is just as fun or you took it as an opportunity to try something different. There are a lot of cool cars out there I’d like to try. If I had to do it over again maybe I’d try a Golf R or a Q50 Redsport or a 335. Price was the deterrent to all those cars 4 years ago when I bought the G37S so bang for the buck it’s hard to beat the Z or G37 as a GT car. I don’t need to daily drive the car anymore so something a little more extreme like a used Camaro ZL1 or a Corvette come to mind as does a Cayman or Boxter or BMW M car but the price-point is obviously higher and so are the repair costs which is why I’m still very into what I have.

    1. Hi Aaron, I have a g37s sedan that I have turned into a time attack track car. I definetly feel the transmission is the weak link. I really love the paddle shifters over a manual. Would you recommend this upgrade for the track? Does it make the car faster or just feel faster?

      1. @Tom,

        Sorry I don’t have timed verification for you on the quicker shifting. I didn’t take the car to the track before to see how the car performed to then have a measurement after. My main concern was removing the weak link in the powertrain when we add more power. I would definitely recommend this transmission for the track with the note that you should add both an oil cooler and a transmission cooler. Stay tuned and you might see an article on that soon ;). The 370Z and the G37 both seem to do a pretty good job of running the fluids hot.

        I really do wish you could experience the Level10 transmission yourself beforehand to see how much better it is.

  3. Ah man, I wonder how the good Dr. is doing. I loved watching the progress of his SE-R build with the transmission and turbo kit.

  4. @Khiem, well I feel the same way about your S2k. This one has been fun as it has gone from daily driver to weekend toy. Hopefully, like you we’ll get to add a lot more power.

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