Yep, I confirmed that the other day. Bounce bounce bounce. I was driving on the onramp merging with traffic, I hit the top of 2nd before I could upshift because I was looking over my shoulder. For some reason I remembered the Z upshifting on it's own in the past, but I guess I'm wrong.

 

It may just be me, but it delays the upshift if you're giving it WOT...

I tend to ease off the pedal for half a sec after I hit the shift to encourage it to shift.... also makes it more fun when I hit the gas again and it's in the right gear...

for best mileage, leave it in D, I use the manual mode when I want to have fun...

 

I was talking about if you don't choose to shift at all. If you hit redline, the transmission will just bounce off the limiter when in manual mode. It won't upshift for you.

I have also noticed that when you are driving hard, it does delay the upshift after you actually push up. So I try to anticipate as necessary. It seems to me the transmission reacts more quickly to downshifts than to upshifts.

 

Wtf I can go 60mph on 2nd gear? Why does it matter when your shift point is for a 5at? It's automatic.

 

Shift when she screams!

 

I'm talking about when you're in manual mode with the auto.

 

For best results is to shift at redline in each gear while in manual mode. Also make sure TCS is off.

 

In manual it doesn't upshift, but I guess that's been said here already.

The automatic is very slow to react though, both in Auto and in Manual. I was constantly hitting the rev. limiter in Auto at WOT. Even in Manual it just took the transmission too long to follow up on the upshift to not hit the limiter. (I must admit, at that time I had the ATI procharger and some other mods).

I had my ECU flashed and the Rev Limit was set a little bit higher. That took care of the problem but I still felt the automatic was way too slow (when drag racing especially ).

I then had the valve body "re-done". The car is now completely different. At lower load you don't feel it shift at all. At high load (like WOT) it snaps your head back, so fast/short/agressive does it shift. Great mod, but you have to send your valve body out and it isn't really cheap...

Danny

 

The reason you got a slow or delayed shift is because you lifted off the throttle. While upshifting the 5AT, you want to be at constant or accelerating throttle. Drive it aggressively and shift without lifting off the throttle and it will shift fast enough to sort of kick you when the gear changes.

If the shift speed still isn't fast enough for you, look into aftermarket valve bodies and ECU upgrades.

Also, as noted above, some FI systems don't play nice with the AT and require other mods.

 

Someone figured out these numbers, not sure who.

Gear Ratio
1st - 3.357 176220/3992.95008 44.13 MPH
2nd - 2.264 176220/2553.683328 69.00 MPH
3rd - 1.472 176220/1660.345344 106.13 MPH
4th - 1.000 176220/1127.952 156.23 MPH
5th - 0.834 176220/940.711968 187.32 MPH
Reverse 2.370 176220/2673.24624 65.91 MPH

 

I can't speak for 4th and 5th, but 1, 2 and 3 seem right if not close. Thanks.

 

Those numbers looks pretty close comparing with calculations made @ http://www.f-body.org/gears/

 

187 for 5th.. has anyone even surpassed the 160 without major modifications?

 

Thank you. You made my day with this advice. I took out the Z and felt the difference on the straight with the shifts.

 

Raise the stall speed on your torque converter by about 200-300 RPMS and you'll have some real fun and still be streetable.

 

200-300 RPMS huh...........hmm i think ill try that thx again with your earlier reply

 

You can probably do a high stall mod for about $700 with install. It only takes a few hours to do and is the best bang for buck you can do on an AT short of FI.

 

The theoretical top speed is 187 with no wind resistance but my guess the actual top speed without the limiter on would be 168 or slightly less. There are two reasons. First, the original equipment tires are W rated which is 168. Today, car makers are not going to risk a lawsuit for having tires that cannot take the speed. For example in the three Lexus I have owned they always had V rated tires eventhough my wifes RX 330 is limited to 112. Second, in every car I have driven on the Autobahn they would not pull the maximum MPH in the overdrive gear. Since the Z is more powerful than anything I have driven there I think the car could do 168 in 5th gear.

 

Mine stays in gear until I shift it despite redline.

 

Heres the page from the service manual, dont know if this sheds some light. I used to have an auto and I could hit 100 or 101 sometimes in 3rd when I pushed it into the redline so the speeds are on the conservative side. The gear ratios are different from whats posted above. Hope this helps. I let it bang off the limiter several times over the 2 years that I had the 5AT and it wont shift when in M mode.