Rev Matching to second gear
 

This is my first manual so I have a simple question that I haven't been able to find through search. So I've been able to rev match well going to 5th, 4th and 3rd well but not to 2nd gear. I'd say I blip it about 700 rpm to get a smooth downshift without lunging forward in the other gears. I've tried a few times rev matching to second and it's a horrible feeling. I want to get a reference how much to blip because I feel that I'm going to wear down my clutch or mess up something before I figure it out.

So how much do you guys blip the throttle when going to 2nd gear (with or without A/C on)?

It's easy to do. Depends entirely on vehicle speed, though.

-alex

Hmm...it varies with speed. I didn't know. I'm planning to go to the dragon in a few weeks so I need to get this down. I've been trying to down shift from 4000 rpm. I thinks that around 45 mph?..maybe.

Just drive the car up to 45MPH in 2nd gear, see what RPM you are at.
Then whatever RPM you are in 3/4/5, take the difference. That's what you need to rev the engine by to match RPMs.

-alex

I don't know I didn't think of that. Dang it!:bonk:

Like Alex said, it completely depends on vehicle speed. Keep in mind that redline in second gear will be at 59mph. So from 3 to 2 at 59 mph, 7400rpm. 50 mph, ~6000 rpm. 40mph, ~4500 rpm, etc. First gear is the same idea. Redlone is at 35mph. 2 to 1 at 35mph, 7400 rpm. 25 mph, ~5200 rpm, etc.

No it does not

If it takes 1000 RPM difference to shift from 3rd to 2nd at 50 MPH, then it takes 1000 RPM difference to shift from 3rd to 2nd at 20 MPH.
Unless you have a CVT of course.

OP (I will get flamed for this) try downshifting from 3rd to 2nd without the clutch.
Get rolling at ~35 MPH in 3rd.
Blip the throttle and slide it out of gear (the blip will relieve pressure on the gear stack)
increase revs by ~1000 RPM and ease it into 2nd (no clutch).
You will likely grind a couple of times trying this but unless you are using a gorilla grip you wont hurt it.
My bet is that you will get it before the 4th try.
Now that you understand that, experiment in different gears.
I have a video of me shifting from 1st all the way to 6th and back to 2nd without ever touching the clutch and ZERO grinding.

This is not a skill you would ever use in performacne driving, but it DOES help you to understand rev matching.

I drove my Karmann Ghia for months with NO clutch using that method.
To start at red lights, I had to turn the engine off, put it in first and start the car...

Your response suggests going into the next lowest gear, i.e. 4 to 3 or 3 to 2.

My response "entirely dependent on vehicle speed" is assuming you are shifting from any other gear or even neutral.

Both are correct.

-alex

This is my first manual car as well, i learned to rev match pretty quick but i always had some problem rev matching when downshifting from 3rd to 2nd. What i do is, i hit the throttle twice really quick and that seems to works very well for me.

1- Clutch in
2- Hit the throttle twice very fast
3- Move from 3rd to 2nd
4- Release clutch slowly and continue to hit the throttle

Just keep in mind that this has to be done very quick. If you take too much time when pressing on the clutch, your RPMS are going to go too low and it will be more difficult to rev match.

I feel like if the RPM gap was always the same, shifting from third to second at 10 MPH would take you from ~800 RPM to around 2700 RPM, since doing it at 60 MPH will increase RPM by about 2000.

I am going to have to pay attention to what I do! Been doing it so long it just sort of happens and sitting here thinking about it I don't have a clue how I actually do it.

Why don't you just double clutch downshift from 3 to 2?

I find that if the gearbox is cold, I have to double clutch downshift from 3 to 2, otherwise 2nd gear will be very hard to engage. Once it warms up then rev-matching or heel and toe from 3 to 2 works fine. Upshifts seem to be fine for all gears when cold, I don't beat on my car (4k rpm max) until the temp is nominal.

I also might get flame for this but running Eneos Gear Oil / Subaru Extra-S GL-5 gives you much better quality 1st and 2nd gear shifts (new generation of GL-5 oil don't eat into yellow metal).

Also if your engine speed is very slow, just double clutch it from 3 to 2 so that you can build up enough revs for 2nd gear.

My HVAC is always on Auto, if it's on Full Auto (A/C on) then I tend to release my clutch slower when driving to ensure smoothness.

Yeah, im not very familiar with double clutch and i haven't try the hill and toe method yet.

I havent really used my AC yet. Do you really feel a different when the AC is on while shifting gears?

Stu it's not the same RPM shift at every speed.. look at any RPM vs Speed graph for all gears and you will see they are not parallel - here is an example

You are right, I am wrong.
I was picturing the engine RPM vs drivshaft RPM graph having all of hte lines parallel.
However all 6 gear plots have y-intercepts of zero, so the lines are not parallel.
So transitioning from one gear to another when low in the RPM range is a smaller jump than doing it at high RPM.

Sorry bout that.

Because double clutching is a method used in trucks (and sometimes cars) without synchros.

If you have a modern transmission with a synchro, there would be zero need to double clutch unless you are doing it wrong or hesitate too much between shifts.

-alex

I found it hard to rev match in this car when I first got it. I think it's due to the DBW and I feel that the pedal response is sluggish. I definitely notice a little dead zone area when I push the pedal down about 1 cm. Maybe I was spoiled by my old MR2 that uses a throttle cable. loved the response with an actual cable instead of this new electronic crap. that and the clutch pedal is one of the things I still haven't gotten real used to in this car yet.

This is correct there is no need to double clutch due to synchros (triple cone synchros too for the first 3 gears in this car) but it's just another skill to have, very useful when the gearbox tends to hesitate 2nd gear in very cold winter mornings.

Yes DBW and dare I say electric steering also, no matter how good they get just can't replicate the responsiveness and feel of old skool cable throttle and hydraulic power steering.

Clutch in, Blip the throttle, Downshift.

This doesn't work for 2nd gear??

No need for double clutching.

I think going in to 2nd needs a slightly bigger blip then the other gears. I'll have to see when I drive it.

I have a question to ask on a related topic.

When peformance driving, is there a general RPM which, once you drop below, you downshift so as to remain on power? IE, Revs drop below 4.5k you downshift. Drop below 5k. Etc.

I ask because I put myself in a dangerous situation, both mechanically and mortally, by under revving on a downshift when going around a corner.

The situation: Navigating a diminishing radius corner, third gear but decelerating gradually as the corner got tighter. Next their comes a pretty sharp kink--I was going around 50-55, can't be sure. Revs at/around five. I go for it, initiating a quick heel/toe which I didn't match properly. Think I needed to hit near 6.5 or so, which I didn't. Don't know how much I missed by, but the rears locked as I was turning in (still on the sweeping part) and as a result my rear kicked out alarmingly quick. Thankfully I caught it. Dangerous situation I put myself in; my nose was angled directly toward the ditch. Desolate road so there were no oncoming cars ( I could see through corner.)

Anyways, haven't driven that hard since then, which was a couple weeks ago, nor have I returned to that road.

So you downshift when you dip below what RPMs when performance driving? I'd like to find out if there is a sweet spot most people adhere to.

For whatever reason when you blip the throttle going from third to second the rpm's don't rise as fast as going to other gears. Next time watch your tach as you downshift through gears and you will see the difference. Iv had good luck just giving it a split second more on the throttle going into second

If I'm not on the track I'll let the revs drop pretty low. I'd probably try to stay above at least 4k in hard street driving, that way you're not in the torque dip.

Blip twice that's what I do works every time

Why not just give it a bit more throttle?

Electronic Drive By Wire
 

good observation for this being your first manual car. 2nd gear is a bit more difficult to downshift to.

First off, the stock Electronic Drive-by-Wire doesn't make it any easier.
It's a bit miss leading as far as throttle, speed, & gear.
My DC2 (cable throttle) felt easier to downshift into 2nd, using the same amount of throttle in any gear.

Secondly, 2.188 gear ratio and 4.100 final is fairly short when you compare it to other gears.

So, you have to give it more throttle than if you were downshifting from 4th-to-3rd.

just as an example downshifting from 3rd-to-2nd:
while in 3rd gear at 25mph give it to about 3100rpm then shift. It should go right in! However, notice it feels like you have to give it more throttle than if you were downshifting from 4th-to-3rd.

I find it more controllable and smoother shifts when I blip once, it climbs a few hundred rpms which puts the second blip already on a head start in higher rpm, then again I also tend to mostly engage 2nd on the coming down of the second blip when downshifting. If I was driving through a very spirited course or track I'd probably just give it a bit more throttle like you mentioned.

I am referring more to daily driving for blipping twice.

like everyone else said. clutch in -> blip throttle -> throw it into lower gear -> let clutch out. eventually you will get good at it and do it one fluid motion.

however with hard driving you will want to heel-toe. same as above except you are using your toes to brake and your heel to blip throttle

practice, practice, practice... thats the only way you will get good. I found the BRZ to be very easy to heel-toe.

Thanks again. I tried your method today and it works great. Now I need to practice the spirited way since I have this boost of confidence. :thumbup:

Applaud to you man, most people are too embarrassed to share their lack of something especially on a forum, I respect that. Glad to hear your getting the hang of it. Now youll really enjoy those twisties when you go.