Nealoc187

iTrader: (23)

This is a copy and paste of SteVTEC's dyno analysis to determine optimal manual shift points. The images are broken, but the text still explains things pretty well.

1995-1999 Maxima Shift Points (USIM)

Below is a dyno and gearing analysis of the 1995-1999 Maxima manual using a stock Dynojet dyno. 1st gear you'll want to hit redline, but the 2-3 should be short-shifted around 6300, and possibly the 3-4 around 6000-6100. The calculated optimal 3-4 shift point is at 89 mph, but because you're just short of the 1/4 mile line at this point, it may be better to just hold 3rd. A shift costs you time and the car is rolling without acceleration while you're shifting. Some people have been able to get better times by holding 3rd, but others have gotten better times by shifting quickly to 4th. It depends on the car and how quickly you can shift. Obviously as you add mods you'll be reaching higher speeds earlier and you'll have no choice but to shift to 4th.


1995-1999 Maxima Shift Points (MEVI)

I translated a stock USIM dyno awhile back to what it would look like if it came in the US with the MEVI standard. Now here's that same dyno in my dyno/gearing analyzer. It's easy to see now how holding the torque curve flatter at the top-end can help you. The optimal shift point is always redline, because the torque curve never falls off enough to truly warrant shifting to the next gear - it runs out of revs first. This is why the JWT ECU with the extended rev limiter (up to 7200 rpm with stock valvetrain) complements the MEVI so wonderfully. Instead of having to shift at just 6550 rpm well before the engine runs out of usable torque, with an extended limiter you can then use every last bit of torque and RPM the engine has at the top end. This is the same problem that a lot of Hondas run into. Lots of torque at the top-end, but not always enough revs to make full use of it.

If you look very closely, you can see how the USIM does give better low/mid-range acceleration but just drops off at the top. And looking on the far right, you can see that an otherwise stock 4g with just the MEVI will pickup about 5-6 mph of top speed. (I incorporated drag calculations also. ) Calculated top speed for the stock USIM is 137 mph which was reported by several mags. The MEVI will do about 142-143 mph.


2000-2001 Maxima Shift Points

Having seen the 4g MEVI charts, the 5g 2000-2001 should look pretty much similar because the powerband is about the same. Redline in every gear for the VQ30DE-K because it holds torque much better up top with the variable intake manifold. Like the MEVI 4g's with the JWT ECU, the DE-K engine could also badly use an extended rev limiter because there is still plenty more acceleration to be had in the current gear by the time the engine reaches the 6600 rpm redline. No need to shift just yet, but you're not given a choice because there aren't enough revs to play with. The 4g MEVI guys with the JWT ECU and 7200 rpm limiter can pickup three-tenths and a few MPH or so at the track thanks to the limiter extension (and improved mid-range torque), so DE-K guys could expect the same, if an ECU is ever released.


2002-2003 Maxima Shift Points

The VQ35DE 5th gens are rather interesting. These are the first VQ engines with CVTC (Continuously Variable Timing Control). This is a "phase shifting" variable valve timing system that optimizes torque primarily in the low-end and mid-range. VQ engines were already praised for their torquiness, and the VQ35 is even more so. It also has a variable intake manifold to widen the powerband also.

As for shift points, the 1-2 should be made at redline, and the 2-3 should be made maybe slightly before redline. For the next two shifts, however, it really isn't necessary to nail a precise point. The torque falloff in the current gear and the torque available in the next gear actually run right on top of each other for 350 RPM. So you can shift at or close to redline like before, or you can short shift a little bit and you should theoretically still get the same performance. The 5-6 is different though and there is a specific point you'll want to nail which is 143 mph and 6000 rpm. Try at your own risk.


1992-1994 Maxima SE (VE30DE) Shift Points

3rd Gens still get love.

With Nissan's Gen1 NVCS system in place (assuming the VTCs are still working ) and the variable intake manifold on the manuals, the old VE motor has better top-end than the popular 4th gen VQ30DE. The gearing is the same between all of the 3.0's, and the VE can hold the torque curve flat enough that you can pretty much shift at or close to redline in all gears with perhaps only very slight short shifting needed.

Note the optimal 3-4 shift point for the VE at 95 mph vs the 4g VQ at 89 mph. This means that the VE will be able to hold 3rd through the 1/4 mile whereas the VQ will either be wheezing at the top of 3rd struggling to finish, or having to get shifted to 4th which costs time. Overall due to more torque and lighter weight, the VQ is a tad quicker, but the VE is no slouch and will give a VQ a good run from a roll. Note also the higher calculated top speed of the VE in the low-140 range vs the high-130 range of the VQ. VE power!