Possibly a silly question, but it has me slightly worried...

[monkey_boy]

So i was taking a mate out for a driving lesson in the 'rona and she neglected to use the clutch from 1st to 2nd...

I expected to hear *insert badly graunching gearbox noise*, but it didnt, it just pulled smoothly into second.

I was puzzled by this and it does it into everything but 5th and only at low to medium revs, clutch and gears seem fine and work as per5 usual when taken as directed.

now for the question(s) part:
a) why does it do this?

and b) is it a bad thing?




any sort of advice\answer or abuse for asking dumb questions, will be appreciated and considered as words of wisdom.

[l1ttle_d3vil]

my mates t50 box in his carina used to change gears with no clutch no problems - cos the box was stuffed.

i can change some gears in one of my cars with no clutch and graunching if I have the revs right. same box also pops out of 5th all the time - ive been told the synchros are stuffed.

[Ae92typeX]

I wouldnt do it day in day out, but its nothing to worry about, get the timing correct and you can do it in any manual

[Fred]

no crunching wud be better than crunching =) knew a guy who used to borrow mates cars and thrash em and change gears without using clutch and thought it was rather funny, as u can guess he dont have a lot of mates now haha

[monkey_boy]

I wouldnt do it day in day out, but its nothing to worry about, get the timing correct and you can do it in any manual

thanks guys, im most happy to hear that.

I think i'll just use the trusty 1L auto Subi justy for driving lessons from now on tho and leave the corona out of it for now

[BZG Wagon]

Its called a 'rev change' and its completely normal. It actually saves your clutch and it doesnt do any damage to the gearbox (if done properly).

If you give your car some gas, and come off the accelerator at the same time as you push your gear lever out of gear, it will pop nicely into neutral. The hard part is usually trying to get it into the next gear.

If you, for instance, are sitting in 4th gear at 3600rpm @ 100kph, then you should be able to go from neutral @ 100kph into 4th gear if you rev your car up to 3600rpm and pull the gear leaver into 4th at the same time.

[ollieboy]

Its called a 'rev change' and its completely normal. It actually saves your clutch and it doesnt do any damage to the gearbox (if done properly).

If you give your car some gas, and come off the accelerator at the same time as you push your gear lever out of gear, it will pop nicely into neutral. The hard part is usually trying to get it into the next gear.

If you, for instance, are sitting in 4th gear at 3600rpm @ 100kph, then you should be able to go from neutral @ 100kph into 4th gear if you rev your car up to 3600rpm and pull the gear leaver into 4th at the same time.

Yeah my dad used to have a car that you had to do this to change gear. It was some stupid British car and they came factory without a clutch with a manual gearbox. It was a long time ago when dad used to live in England so were talking about 40 years ago.

[RedMist]

Its called a 'rev change' and its completely normal. It actually saves your clutch and it doesnt do any damage to the gearbox (if done properly).

Yeah my dad used to have a car that you had to do this to change gear. It was some stupid British car and they came factory without a clutch with a manual gearbox. It was a long time ago when dad used to live in England so were talking about 40 years ago.

Never heard of it called a rev change. Its always been a clutchless shift as long as I can remember. FIRST THING You are talking about two different types of gearboxes. A straight cut gearbox, such as that in a motorcycle, truck, old cars or some racing cars can be clutchlessly shifted without issue. You just rev match gears as stated above. Helial gears, such as those in all production manual cars require a ramp up to engage, hence the synchros. Clutchless changing can be accomplished however its almost certainly damaging the synchros. IE don't do it.

[NZ_AE86]

Never heard of it called a rev change. Its always been a clutchless shift as long as I can remember. FIRST THING You are talking about two different types of gearboxes. A straight cut gearbox, such as that in a motorcycle, truck, old cars or some racing cars can be clutchlessly shifted without issue. You just rev match gears as stated above. Helial gears, such as those in all production manual cars require a ramp up to engage, hence the synchros. Clutchless changing can be accomplished however its almost certainly damaging the synchros. IE don't do it.

Motorcycles and other gearboxes that can shift without disengaging (using clutch) use 'Dogs' instead of Synchros to engage gears. This has nothing to do with the box being straight cut or helial cut, this only refers to the teeth on the gears.
But as redmist says unless you have a 'dogbox' don't change gears without the clutch as you can/will damage it!

[Meadzy]

New subaru wagons do that aswell at the right rpm range

[CozmoNz]

alot of truckies drive like this.... its fine getting up through the 16 gears... its back down again thats the problem.

coris dad had a go driving the road trains in aussie (3-4 long, extreamly heavy loads) basically, if you missed a gear, your fked, might as well just jump out of the cab, coz you aint slowing down bucko.

the brakes worked, but only from 3kmph and under... or the pedal just didnt do shit...

redmist, isnt poping it out of gear fine? its just rolling it into the next that does the damage isnt it?

[BZG Wagon]

If you watch the Bathurst V8 carefully, you will see that they dont bother with the clutch changing up gears to reduce lost acceleration through gear changes. You will see their right foot comming off the gas pedal for a bried second and then straight back on as they change. The left foot doesnt move. I think most Targa Drivers drive simillarly.

I have only ever known it as a 'rev change', but thats probably because its what my dad and his friends have always called it.

When I was a kid, my dad had a problem with his clutch cylinder and it wouldnt disingauge the engine, so he key started the car in second gear and drove from Devonport to Massey without the use of a clutch (1980 Mark II Toyota Coronna - 2L Straight 6 RWD). And thats how I found out about it.

[Dell'Orto]

If you watch the Bathurst V8 carefully, you will see that they dont bother with the clutch changing up gears to reduce lost acceleration through gear changes.

Read the part about dog boxes

[GOLDAE86]

I know it as rev matching, flat changing, and being a lazy idiot. The v8 supercars have straght cut dog engaged hollinger gear boxes.Thats why they can do that.Spend $15k or more and then u can do it properly too

[mr pad]

Hahahaha. Gold thread. Dont do it. Think of the syncros.

[drftnmaz]

we've always called it flat changing and i used to do it all the time until i lost 4th gear foreva... i think it lost a few teeth

[Skidman]

yea, na flat changing is different.
Flat changing is what all the car test mags etc do when changing gear while testing not so powerful cars 0-100 times, and it goes like this.
Floor the car drop the clutch and never let your foot off the gas till you hit 100 kph, including changing gear-using the clutch. You have to be fast as the revs go kinda high if your slow. Awesome stuff for your clutch. its how Autocar??i think? fukd 3 ford typhoons in one day. ! lol, auzzie tanks crack me up.

Back to the orginal post. It will only fuk your baulk rings (quicker than usual) if done properly, if done by an amature you can bruse the teeth of your syncromesh hub-which eventually will cause it not to engage whatever gear.

[BZG Wagon]

Hahahaha. Gold thread. Dont do it. Think of the syncros.

Maybe im wrong, but wouldnt it only damage the syncros if you did it WRONG?

(I.e that nasty little crunch you hear when the revs just arent quite right?).

I have done it in all my cars and never had a gearbox problem?

[RedMist]

Yes flat shifting is as Skidman stated. It can be either clutched or cluchless. You use the rev limiter to create a break in power so the next gear may be engaged There are also ECU's that have a flat shift feature. It simply enables a secondary, lower, rev limiter based on either clutch engagement or pressure on the gear lever.

BZG Wagon, you need to look about two lines above your post to discover your answer.