Race Results with cousins tibby from a stop

[Fredless]

Originally posted by 00firebird:
i am confused, is it faster to leave it in drive or shift it yourself

for the old 700-R4's and 4L60's, shift it yourself.

For the electronically controlled trannies like we have 4l60-e's, let the computer do it. It lags when you shift it, tried it once, never again because I held it till 5700, and it took a while to register that I moved it up...thus it hit the rev limiter. Yeah I ran like a 16.1 that time down the track.

When I race, I just leave it in OD and launch and go. I agree with what batmobile said, its gonna shift at the programmed WOT shiftpoints regardless.

[Harry94]

Good kill. Nice to see that other 3.4s are putting up a fight. Nice car BTW. Sometimes wish mine was white.

[Camarorulz]

There's no reason to manually shift your automatic. All the good automatic racers on this board leave it in OD where it belongs. There is no difference between "D" and "OD" other than in "D" the tranny will not shift into overdrive. This does not matter in racing. Regardless, with the 4L60E being an electronically shifting transmission, the computer controls what RPM and speed the transmission shifts at during WOT, YOU DON'T.

This is different for trannies like the 700R4, which is not electronically controlled.

Good kill btw!! [img]graemlins/rock.gif[/img]

[Robb235]

Originally posted by Camarorulz:
There's no reason to manually shift your automatic. All the good automatic racers on this board leave it in OD where it belongs. There is no difference between "D" and "OD" other than in "D" the tranny will not shift into overdrive. This does not matter in racing. Regardless, with the 4L60E being an electronically shifting transmission, the computer controls what RPM and speed the transmission shifts at during WOT, YOU DON'T.

This is different for trannies like the 700R4, which is not electronically controlled.

Good kill btw!! [img]graemlins/rock.gif[/img]

I disagree with people saying it doesn't make any difference if it's in D or OD.

Instead of rewriting what I've read, I'll just do a straight copy and paste:

"...the computer will shift firmer and hold gears a little longer if you're in 'D'. Its part of the adaptive shift program. When the shifter is in D the computer sees that you're asking for more performance. It will power up the shift solenoids more quickly because of this. Driving around in D will not overheat the trans because the torque converter still locks up.

You could wind the car up to 100 mph in D and then shift into OD before you hit the rev limiter. This won't hurt a thing. Driving around in D won't hurt anything so long as you don't cruise at 70 or better for too long like that. The engine tends to run a little hotter and your fuel mileage drops like a rock because of the increased RPMs. It still won't hurt anything, though.

Also, the PCM does learn your driving style and behaves accordingly. If you've ever driven a car where someone barely gets into the throttle, they're complete turds.

The more often you get your foot in the throttle, the better the engine and transmission will respond. You'll get more spark timing, snappier shifts and above all blow the carbon deposits out of the motor."

EDIT: But I do agree you should let the car shift itself instead of you manualy going 1-2-D-OD.

EDIT 2: Oh, and if you're wanting to read the entire thread you can find it here link

[ January 08, 2005, 12:13 AM: Message edited by: Robb235 ]

[mike h]

there is a "D" and a "D" in a box. the one that borders "N" is overdrive, correct? overdrive is just something that gives you lower RPMs right? what is better for racing, or do you do one for the launch then switch over?

[Jerriko]

This has been argued over and over. Doesn't anyone remember this? It COMPLETELY depends on what trans you have. If its an OBD 2 trans (4L60-E), you don't manually shift it. If its an OBD 1 version (700R4/4L60), you manually shift it. Please, people do a search on this. Has anyone noticed that most people who say NOT to do it have newer cars and most of the people who do it have older versions?

Why don't we have a graelim that is beating a dead horse? [img]graemlins/twak.gif[/img]