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it's a pretty cool trick... my mechanic showed me how to do it... maybe i've just been left ignorant of this and this is a very common little trick that everyone knows how to do, but i never even knew it was possible until my mechanic drove my car w/ me in it---and to my surprise, HE WASN'T USING THE CLUTCH! the reason i never even thought it possible in the first place was because i had no real knowledge about transmissions.... i still really don't know everything about transmissions, but at least i know how they work now.... maybe some one can shed more light on this subject than i can... i could be wrong, but i think it has a similar idea behind it as "double-clutching", except w/o hitting the clutch once, let alone twice...

i'll try to explain how all this is possible and how to do it (to the best of my knowledge)... but correct me if i'm wrong, because i'm not claiming to know everything by any measure--just simply sharing... also, i haven't really got the trick down pat yet, so maybe i have major misconceptions:

basically, let's say u're driving along in, let's say, 4th gear cruisin' along at 4,000 RPM's... u would then proceed to knock the shift knob into the neutral position... after u've done this, u've allowed the engine's RPM's to fall, while the output shaft from the transmission is still spinning fast (as evident from the wheels still spinning--the car's still coasting!)... the next step would be to rev the car up to the same RPM's as the output shaft at the transmission, so that the collar can mesh with 5th 'freewheeling' gear still being spun by the layshaft (the layshaft is still spinning since we're doing all this w/o touching the clutch)

the next part is the tricky part... having a good knowledge of the gear ratio's will aid the driver in estimating the engine RPM range to aim for (i personally have no idea what the gear ratios are for the mx-3, because my mx-3 is automatic, and my nissan is the stick)... what u're aiming for is to get the engine and tranny's output shaft spinning at the same rate... since a 1:1 ratio is common for the fourth gear, we'll just use that for the sake of ease...

because the rpm's fall as soon as the tranny pops out of 4th gear into neutral, we need to rev up the engine... if when u popped the tranny out of 4th gear u were goin along at 4,000 rpm's, you would just simply rev up the engine back to 4,000 rpm's and shift into 5th gear, w/o needing the clutch....

well, the reason i posted all of this was just as much for me as for anyone else, because i wanna see if my conceptions of what is happening inside the tranny is REALLY what's happening...

thanks

That trick has been around for a long time.. commonly known as "Speed Shifting".. and yes.. it takes a real knack to master.. I decided not to do it anymore after I toasted the clutch in my subaru doing that LOL

Tunes67

Tunes67 wrote:That trick has been around for a long time.. commonly known as "Speed Shifting".. and yes.. it takes a real knack to master.. I decided not to do it anymore after I toasted the clutch in my subaru doing that LOL

Tunes67

i guess that's a good enough reason... lol

Thats a trick used mostly in trucks and road racing. You shouldn't do it with a tranny that uses a synchromesh though. You'll end up grinding the fine teeth off of the gears. Thats what makes a shift nice and smooth. If you've ever tried driving a car with straight cut gears you'd see why this is important for daily driving. I drove F2000's with straight cut gears and I can tell you that at low speeds they are terrible. But at high speeds without the use of the clutch it's amazing!!! I'll look around for a picture of a synchro gear and a straight cut gear to show you the difference and what your grinding off by not using the clutch..

mazdubber wrote:Thats a trick used mostly in trucks and road racing. You shouldn't do it with a tranny that uses a synchromesh though. You'll end up grinding the fine teeth off of the gears. Thats what makes a shift nice and smooth. If you've ever tried driving a car with straight cut gears you'd see why this is important for daily driving. I drove F2000's with straight cut gears and I can tell you that at low speeds they are terrible. But at high speeds without the use of the clutch it's amazing!!! I'll look around for a picture of a synchro gear and a straight cut gear to show you the difference and what your grinding off by not using the clutch..

yea, i've seen a 'cartoon' pic of what it looks like, but more pics would be nice... i do have a mental picture of what it looks like though, just never seen a "real-life" picture of one... but basically i think it's a protruding cone on the gear that would insert into the collar to smooth things out, instead of the 'dog teeth' having to catch all the torque of the spinning gear... i guess the idea is to allow the collar and gear to make contact creating friction, which 'synchronizes' and smooths things out...

Here is a straight cut gear.


This is a synchro gear. They vary greatly in design for these.

lol...I found those 2 on ebay.

To really learn how to do this get yourself a rental car for $30/day with a standard transmission!

SimonPK wrote:To really learn how to do this get yourself a rental car for $30/day with a standard transmission!

people also say in order to learn how to drive a 5 speed u should rent one...

but i heard that for that reason, rental companies don't rent out stick shifts anymore, cuz they wanna avoid people screwing up their cars.... i mean, how can u prove how much damage is done to the tranny after a person uses it? when a person doesn't own the car, he'll probably abuse it more than he would his own car... ya know what i mean?

I have always been able top float gears..its simple... a year later..i got a busted bearing...the clutch is fine.. the bearing is whats gone..dont klnow if it had anything to do with that.

It is a really cool trick. I mastered it in my RS but I haven't tried it on the GS yet.