VDC not very intrusive?

UNKNOWN_370

How would you rev match without a clutch?

ImportConvert

Automatics have clutches. Even ones with tq converters. Also, hydraulic lock-up is indeed following the same concept as a clutch, it's just viscous.

UNKNOWN_370

I understand that. But I mean functionally. If DRM is disabled or not working properly when VDC is off? And we need to blip the throttle with no manual clutch? How do we still achieve rev-matching manually without computer assistance? That's my question.

m4a1mustang

My guess is we probably can't without assistance.

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wstar

Re manually rev-matching the 7AT:

I don't think it would hurt it in the short term to play with it for a few days. They take a lot of abuse and keep ticking, and it's really just some shocky engagements while experimenting.

SRM isn't disabled when VDC is off. This was just a side-topic that sprung up about SRM being disabled when ETC is off. ETC stands for Electronic Throttle Control, and can only be disabled via UpRev, not dash buttons. In the 7AT case, when you click a shifter paddle, after a short delay the compter goes through a sequence of clutching out of the old gear and into the new gear and blips the throttle in the middle. The question is whether it's practical to time that out manually and do it yourself or not. It's definitely theoretically possible, just possibly impractical.

The Service Manual has some pictorials about the underlying processes, e.g.:





The last line there "Engine Speed Control Demand" basically means "The time window for which the TCM wants to control your throttle for blipping purposes". With ETC off it can't do so, and you have to do the same with your foot.

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