Hi,
I'm wondering two things :

1. Is it safe to start on 1st gear all the way to top revs? Engine im optimal temps of course
2. Is it safe to downshift from 2nd or 3rd gear at, let's say 20mph for rapid acceleration?

 

1. Yes. Assuming safe road.

2. Rarely, if ever, should you do ANY downshifting FOR ACCELERATION without rev matching. If not for performance then at least for ease on the equipment. And downshifting to 1st gear at anything above about 5mph, well, can't see any reason to do so.

 

Hmmmm

Why did the ummmm guy shift from 3rd to first....



Rapid acceleration

 

Of course I'm rev matching. So downshifting from 2nd at let's say 20km/h (about 12 mph} is a no no?

 

Not necessarily a "don't-do-it" but I cannot think of any corner requiring a 1st gear exit. Never done it in 40+ years.

But.... let your tach be your guide.

 

Not during cornering. Let's say, I drive behind a learning driver on a single lane @ 12mph. Suddenly, a wild second lane appears! Revs on second gear at 12-15mph are much too low for good acceleration so I was thinking about rev-matching to 1st gear and downshifting. Let me question this - Is it ok for transmission/engine to downshift to 1st gear when revs are matched? I'm not really questioning if downshifting to 1st gear is good idea or pointless. I just want to know how it affects car's reliability. Thanks.

 

When done properly, itll be fine on the engine and tranny, however, at 12-15mph thats very little room left for acceleration before havent to shift again. 2nd is good enough. It may not feel strong, but thats purely due to gearing.

 

OK. Thank you for your replies