downshifting

[s15dude]

I was talking to a friend of mine and he said that downshifting while braking is a bad idea cuz it accelerates wear on the drivtrain. I understand that there would be extra wear on the clutch but would the whole drivetrain wear out faster?

[LanceS13]

:confused:
The wear from the extra use is very minimal and directed towards the clutch if anything as long as you rev match and don't overwork the synchros.  You're supposed to downshift while braking.  Just throwing it in nuetral leaves you at a big disadvantage when you have to react in the event that you need to take evasive action.  Supposedly, downshifting also saves gas.

[HippoSleek]

I can't imagine downshifting saving gas, but I agree that it provides minimal wear on the driveline if done correctly.  If you don't rev match, sure - there will be clunks which are bad, but if you do, it should be as smooth as upshifting.

Honestly, while I do it, I don't see any huge benefits when you are coming up to something like a stop light (except that if it turns green you are ready).  Where it helps is coming into corners when you need to be able to get back on the gas in the proper gear for exit speed.  It allows you to brake (in a straight line) and downshift to maximize you decelaration and your place in the power curve.

[sspikey]

heel toe downshift = good

[LanceS13]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">Quote: from HippoSleek on 7:58 am on Jan. 29, 2002
I can't imagine downshifting saving gas, but I agree that it provides minimal wear on the driveline if done correctly. </td></tr></table><span id='postcolor'>
I think it has something to do with the injectors pumping less while the car is decellerating in gear than they do at idle (car decellerating in neutral). &nbsp;I'm sure the difference is minimal, but you know...whatever.

[Nismos14]

do the injectors feed different amounts of gas when they are in different gears?

[transient]

Actually, I think lance is right, if you think about it, when you downshift the injectors don't have to pump gas to hold an idle speed like they would in neutral.

[HippoSleek]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">Quote: from transient on 4<img src="http://www.zilvia.net/f/iB_html/non-cgi/emoticons/wow.gif" border="0" valign="absmiddle" alt=':0'>4 pm on Jan. 30, 2002
Actually, I think lance is right, if you think about it, when you downshift the injectors don't have to pump gas to hold an idle speed like they would in neutral.</td></tr></table><span id='postcolor'>
Not if you rev match. &nbsp;Going into neutral, all you have to do is allow the flywheel to slow down - w/ downshifting, you have the driveline forcing rotation of the engine which, I would think, would require gas.

I may have to do some research on this one b/c now I am really curious?

[rampid360]

</span><table border="0" align="center" width="95%" cellpadding="3" cellspacing="1"><tr><td>Quote </td></tr><tr><td id="QUOTE">Quote: from s15dude on 2:47 am on Jan. 29, 2002
I was talking to a friend of mine and he said that downshifting while braking is a bad idea cuz it accelerates wear on the drivtrain. I understand that there would be extra wear on the clutch but would the whole drivetrain wear out faster?
</td></tr></table><span id='postcolor'>

The only way i can see downshifting as being hard on the drivedrain is if you are using it as a primary stopping method. (say for instance your brakes are shot and you are too lazy to fix them...so you downshift until you are going slow enough for them to stop you) &nbsp;
You didn't specify if you were stopping for a red light or braking for a sharp turn.

[Nismos14]

im curious about the gas while downshifting also i wonder how it would work... hmmmm