[tetra]

To the guys with automatic trannys, does your Duratec 2.0L get you off the line better with overdrive off or on? I noticed overdrive tends to rev higher since it's 3 gears instead of 4 when OD is on?

 

[nardvark]

Don't think it makes a bit of difference off the line, because 4th gear doesn't kick in until at least 5 seconds in...

 

[levin.matthew]

i don't think it makes any bit of difference man

 

[flipwilly2]

If you're "on it", OD won't kick in until you ease up in 3rd gear.

 

[Brindfan]

No difference.

 

[CJohn364]

No difference. OD won't pick up until the higher gears.

 

[tetra]

Ahhh I see, I could of sworn I seen the RPM's rev higher with OD off, must of been my imagination lol.

I noticed though when OD is off, there is Engine Breaking as described in the manual, does this affect wear? I'm not sure if this is a new feature on 2008-2009 models, but the car definitely slows down better when OD is off for city driving.

 

[bdnld4482]

a tune and a tb would help out so much better for the atx guys

 

[jetrinka]

Engine braking is when the transmission either stays in a lower gear or shifts into a lower gear to slow the car. So with overdrive off the car doesn't have the option to shift into that higher gear while coasting so you will get a slight braking effect from the lower gear and the car working against its own compression, stopping the car.

 

[nardvark]

well, if your car was holding onto 3rd gear instead of shifting into 4th, your rpms would have been higher there. But I don't think this should affect 1st and 2nd gear.

Generally you would use OD to engine brake in a very hilly area, so your brakes don't fade and warp due to excessive use.

 

[CapnGnarly]

My best starts (on my auto) have always been variations of the same.

Left foot on the brake pedal, not hard, just enough to keep her in place. OD off, put it into low gear (1). Apply slight pressure to the accelerator so you're sitting around 2k rpm, I've launched as low as 1.5k, and up to 2.7k, but the best effect is around 1.8-2k. When the christmas tree says go, change your feet around so your gas is mashed and your foot is off the brake (duh...)

Shift to high (2nd) around 5.8k (it'll respond by 6.2 ish, where you want to shift), keep the pedal mashed (you don't need to "let off" on an auto), then same thing, drive her up to around 5.8k rpms and push the shifter up to drive. As you do this, hit your overdrive button to turn it back on, then put your hand back on the wheel (it was there after you started, and then again after you shifted to high gear if you know what you're doing), and you're rolling until your car don't want to go no faster.

In essence, 1 -> 2 are without OD, then as soon as you go to D (3rd gear if you hit it right, you'll feel your car shift), turn your OD back on so you don't end up engine braking at the end of 3rd.

This is also a good setup for auto-x in automatics. If you're in low/high gear, keep OD off, if you're in drive, turn it on.

 

[tetra]

Thanks for the explanations guys, makes a lot more sense to me now.
About the tune, I want to get one but I have to wait until SCT comes out with a 2008-2009 tune. Then I will get it along with my header and exhaust.

Can't really upgrade the TB since it is electronic, the only thing I can do is add a spacer right now I believe.

 

[nardvark]

Capngnarly:
not sure I understand you...why bother having your OD off if you're just going to slap it on as soon as you shift into 3rd (ie: D with OD off)?

 

[Blackcatn2o]

If you were to manualy shift it, once you get into drive (with the O/D off) you would be in 3rd gear then if you turn it back on then you would be in 4th.

 

[CapnGnarly]

The shift into 3rd will drop you down to around 3.5k rpms, and hitting OD doesn't turn it on right away (a good 1-1.5sec lag on it). So basically it drops you down to your highest torque rpms (3.5-4k), then pops it into 4th, kicking you down to 2.5k rpms letting you get a full run in "4th."

 

[DURATECoftheDesert]

It's probably the torque converter stepping in, because the only way to go to o/d/ is if the speed is greater than 38 or 40 mph.

 

[CapnGnarly]

It's probably the torque converter stepping in, because the only way to go to o/d/ is if the speed is greater than 38 or 40 mph.

Torque converter is around 1750 rpms. You can feel it when you apply slight pressure on the accelerator with your foot still on the brake. You'll know *right* when it hits.