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View Full Version : 5th Gen Auto Gearing for speed



Newbster
07-09-2007, 02:36 PM
Well I was racing my friend the other day, we both have autos, around the same HP. We were pretty much neck and neck the whole time, but he was about 3-4 feet ahead of me. I also had a passenger while he didnt. But anyway, I noticed I think it was first, or second gear (cant remember) but I stayed in it WAY too long. On autos on full throttle, it doesnt shift until 6500RPM and we all know, torque stops around 5000? I think. Now my question is, my shifter only has L,2,D,N,R,P. So that means I can shift manually around 5k until second gear, but then as soon as I shift into D, whats going to happen? Is it going to retardedly shift into OD? Or kick to 3rd gear for me?

BTW whats best rpms to shift at from 1st to 2nd? 5SFE

Fuelish
07-09-2007, 07:15 PM
. On autos on full throttle, it doesnt shift until 6500RPM and we all know, torque stops around 5000? I think. Now my question is, my shifter only has L,2,D,N,R,P. So that means I can shift manually around 5k until second gear, but then as soon as I shift into D, whats going to happen? Is it going to retardedly shift into OD? Or kick to 3rd gear for me?

BTW whats best rpms to shift at from 1st to 2nd? 5SFE Your torque doesn't "stop" @5000 rpm ...it peaks in and around there somewhere, declining after that, but ..... with an auto, your best bet is to just floor it in D and let the tranny shift when it decides to - and, if you "manually" shift it, depending how heavy (or not) your foot is on the gas , you could conceivably shift from 2nd to D, but the tranny might still be holding in 2nd- if floored yet not redlined (same with shifting into D)...also, shifting into D with a heavy foot should keep it in drive until you lay off the gas somewhat before hitting O/D .... at least in my experience. Also, if you put the selecter in 2nd, you'll still start in L and it'll shift to 2 - just won't shift out of 2nd automatically. Having the ability to "manually shift" an automatic (at least the average auto) is more about the downshifting/engine braking than it is about accelerating. Your tranny knows what to do when accelerating ....

Murgatroy
07-09-2007, 07:17 PM
Your torque doesn't "stop" @5000 rpm ...it peaks in and around there somewhere, declining after that, but ..... with an auto, your best bet is to just floor it in D and let the tranny shift when it decides to - and, if you "manually" shift it, depending how heavy (or not) your foot is on the gas , you could conceivably shift from 2nd to D, but the tranny might still be holding in 2nd- if floored yet not redlined (same with shifting into D)...also, shifting into D with a heavy foot should keep it in drive until you lay off the gas somewhat before hitting O/D .... at least in my experience. Also, if you put the selecter in 2nd, you'll still start in L and it'll shift to 2 - just won't shift out of 2nd automatically. Having the ability to "manually shift" an automatic (at least the average auto) is more about the downshifting/engine braking than it is about accelerating. Your tranny knows what to do when accelerating ....
:stupid:

5S-FE
07-11-2007, 11:25 PM
Hey guys, how does the ECT button work? Does the car just hold the gear it's in until red line and then shift by itself?

Usually I just floor it in D, but I'm gonna give that ECT button a shot. :Ban1:

Murgatroy
07-12-2007, 01:56 AM
The ECT is your 'electronically controlled transmission' switch. You have economy and performance settings. In economy it will shift at a lower RPM. Performance will shift at a higher RPM. However, if you hold the pedal to the floor, it will shift pretty much at redline regardless of the setting.

You also have the Overdrive (O/D) button. By turning this off you limit your car to only 3 gears. If you are racing you can turn this off. However as mentioned, if you are holding it to the floor, it will shift at redline.

Manually shifting an automatic is just advisable for downshifting. It is kinda pointless to upshift. You put the go pedal to the floor, it shifts at redline. It is more reliable and consistent. It will always shift at redline. If you are at greater than 3/4 throttle you will not shift into overdrive.

With that said, I do manually shift my automatic. I use it to downshift because of the way I drive the twisties sometimes the time for the pressure to build to automatically downshift is slower than my flicking off the O/D switch and or dropping it to second. Once I get to where I want to be, I will push the shifter back into Drive.

I also downshift on long downgrades to use the engine to break with.

I have always drag raced with an automatic. In my Camaro I had a ratchet shifter and I would manually upshift and downshift. This was in combination of the raised redline, and removal of the kickdown cable. It was also the best way to make certain of a consistent ET.

extremeskillz
07-12-2007, 02:03 AM
i agree. I wish we could upgrade the damn torque converter to a higher stall converter for better responce or something. One thing lacking for the automatic guys.

Azzazzyn
07-12-2007, 02:28 AM
although manual is super fun to drive, the auto's tend to run faster in turbo model cars.

5S-FE
07-13-2007, 03:51 AM
So if I go O/D off (and floor it of course) will the car will shift at redline for the 3 gears? Same thing if I press the ECT button (so it's on)? (and floor it of course)

I've tried flooring it with overdrive on the car doesn't shift at redline, or atleast I don't remember it doing so. I don't manually shift my auto, I just leave it in D all the time.

Basically if I drive normally with the ECT button, it won't shift at redline, it's just that the car will be shifting at higher revs then compared to driving with the ECT off. Same with overdrive, the car shifts at higher revs because it's only in 3 gears? Do I sound correct or am I confused?

Thanks for your info though, I'm learning something. :D I'm also just trying to figure out the fastest way to make the car catch speed. :cool:

Chris
07-13-2007, 04:12 AM
The ECT is your 'electronically controlled transmission' switch. You have economy and performance settings. In economy it will shift at a lower RPM. Performance will shift at a higher RPM. However, if you hold the pedal to the floor, it will shift pretty much at redline regardless of the setting.

You also have the Overdrive (O/D) button. By turning this off you limit your car to only 3 gears. If you are racing you can turn this off. However as mentioned, if you are holding it to the floor, it will shift at redline.

Manually shifting an automatic is just advisable for downshifting. It is kinda pointless to upshift. You put the go pedal to the floor, it shifts at redline. It is more reliable and consistent. It will always shift at redline. If you are at greater than 3/4 throttle you will not shift into overdrive.

With that said, I do manually shift my automatic. I use it to downshift because of the way I drive the twisties sometimes the time for the pressure to build to automatically downshift is slower than my flicking off the O/D switch and or dropping it to second. Once I get to where I want to be, I will push the shifter back into Drive.

I also downshift on long downgrades to use the engine to break with.

I have always drag raced with an automatic. In my Camaro I had a ratchet shifter and I would manually upshift and downshift. This was in combination of the raised redline, and removal of the kickdown cable. It was also the best way to make certain of a consistent ET.


Chaos is an auto?

Murgatroy
07-13-2007, 12:52 PM
Yeah, Chaos is an Auto, Mudhoney is the 5-Speed.

I find the gearing for the auto much better. Cruising keeps a lower RPM as well.

Chris
07-14-2007, 06:49 AM
Yeah, Chaos is an Auto, Mudhoney is the 5-Speed.

I find the gearing for the auto much better. Cruising keeps a lower RPM as well.


Ah, okay, cool. What does the RPM run at on an auto, at about 70 mph?

Murgatroy
07-14-2007, 12:37 PM
70mph with the 4AFE and an auto is about 2700-2900 RPM.