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I-S
07-07-2004, 06:40 PM
Does the Invecs II box have overdrive?

I've never seen anything about it, but from listening carefully to the engine, and taking careful note of the behaviour of the revs, I think it has overdrives in 3rd and 4th.

Anyone confirm/deny this?

Nick Mann
07-07-2004, 08:02 PM
What do you mean by overdrive?

It has mechanical lock-up in the highest 2 gears. You hear the engine note rise without a gear change sometimes if you accelerate at reasonable speed.

I-S
07-07-2004, 08:34 PM
That's what I'm hearing. Can you explain to the mechanically challenged (hey, I'm an electronic engineer) what that means?

Japmetal
07-07-2004, 08:39 PM
I don't know about overdrive as such, but I do know the engine/gearbox ECU has a learning function, where it adapts to your driving-style. So, those who accelerate gently & drive at reasonable speeds will find their gears change earlier than those who floor the cr@p out of it & drive at higher speeds, since the gears will hold longer to get the added acceleration !

Kieran
07-07-2004, 10:35 PM
The noise you're hearing is normal behavior Issac.

The 4 speed INVECS-II doesn't have an overdrive - instead it has a lock-up function on 3rd and 4th. When it engages you will hear the revs drop about 500 rpm.

What's a mechanical lock? Well, I think this article is good - they explain the entire function of the torque convertor and the lockup without getting gearbox-nerdy on you!

http://auto.howstuffworks.com/torque-converter1.htm

I-S
07-07-2004, 10:42 PM
Got it now. Cheers!