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yeh mine does the same, hell even when trying to go from 3rd to second it sometimes doesnt want to slot in like it should (similiar to what it does going from 2nd to 1st at lower speeds).. synchros are knackered i believe, changed the oil months ago with no improvement.

Can confirm this guy can't drive :thumbsup:.

It really can't be that hard can it?

Every car that I have driven, you have to be going at low speeds to engage first, and even then 9/10 you can't just shift straight from 2nd to 1st, you have to rev match. Just like if you change from any other gear down, makes the transission so much nicer. I know my box isn't in the greatest condition but it's not that prominent with my driving style. I'm skews rev matching when down shifting. And hardly ever go into first on a roll. But when need be, I can do this.

I think practice is in order, seeing as I class myself as a amature. Don't worry about "is it the synchros" just get you're driving style up to par with the car you're driving.

Go drive yourselves an old ford or holden with three on the tree and then complain about a skyline box being hard. I leant to drive in these old pieces of crap and believe me the skyline box is like getting gobbys while driving compared to the old 3 on the tree.

Edited by Room42

Go drive yourselves an old ford or holden with three on the tree and then complain about a skyline box being hard. I leant to drive in these old pieces of crap and believe me the skyline box is like getting gobbys while driving compared to the old 3 on the tree.

I picked up an old LJ once and when driving it home I discovered it had like a black hole between 2nd and 3rd.. 1mm in the wrong direction the shifter went into space and was quite difficult to get back :laugh:

  • 7 months later...

Bringing the old thread back up to settle an argument. Between 2 friends

It didn't seem to fully get touched on after reading all the replies

I have during gear changes doing the following.

Clutch in, rev match while putting into next gear.

My house mate has been going the following.

Clutch in, neutral, clutch out, rev match, clutch in and into next gear.

My question is his technique any better for an r33 gtst's clutch, flywheel or gearbox.

Or is it exactly the same as my technique.

I double dip the clutch on a rev matched shift. It's not just about matching the revs, it's about using the (temporary) connection between engine revs and input shaft (via the briefly connected clutch) to spin the gear cluster up to speed.

Anyone who has driven a truck with no synchros at all will know how to do a proper double declutch downshift.

Edited by GTSBoy

I understand for older cars its needed.

But does it really need to be double dipped on our current 1990 gearboxes?

His understanding is that his is better for the car.

My understanding is that both ways are exactly the same for our syncro boxes

Vintage of gearbox makes no difference. It's still exactly the same mechanisms. A double dip on the clutch, while blipping the throttle, does the same thing in a box with synchros as it does in a box without. It makes the two shafts in the gearbox match speeds. This takes all the load off the synchros - they do not have to do anything - provided you actually do get the rev match pretty close.

if you do not double dip the clutch, then what you are doing with your throttle blip is just bringing the eng revs up to match the road speed in the new gear you are selecting. This does 1 thing desirable - it makes the end of the gear change smooth - so that there is no sudden application of engine braking force to the back wheels. Without a rev match, the engine braking effect can make a RWD car oversteer if you happen to be changing gear in the middle of a cornering event. BUT...what the throttle blip on it's own does not do, is match the speeds inside the gearbox. So the synchros still need to do the work of matching the speeds of the two shafts.

So, if you have worn synchros, then a single dip throttle blip change will do nothing to improve the shift itself. If you wish to not wear the synchros (assuming they are currently good), then the same applies. Only a double dip whilst blipping will do that job.

Which one you use will depend on exactly what you need to achieve. Me, I learnt to drive in an ALFA that had completely thrashed synchros on 2nd and 3rd (and pretty much rooted on 1st and 4th as well). So I learnt to change up a little slower and double dip blip change on the way down. Otherwise you could not drive it at all.

Go drive yourselves an old ford or holden with three on the tree and then complain about a skyline box being hard. I leant to drive in these old pieces of crap and believe me the skyline box is like getting gobbys while driving compared to the old 3 on the tree.

I've got a 1964 Datsun l320, three on the tree :). So fun to drive!

Bringing the old thread back up to settle an argument. Between 2 friends

It didn't seem to fully get touched on after reading all the replies

I have during gear changes doing the following.

Clutch in, rev match while putting into next gear.

My house mate has been going the following.

Clutch in, neutral, clutch out, rev match, clutch in and into next gear.

My question is his technique any better for an r33 gtst's clutch, flywheel or gearbox.

Or is it exactly the same as my technique.

Double clutching = waste of time on the upchange and will wear out your pressure plate and thrust bearing faster.

On the downchange is a different story. There are benefits to it, as explained by GTSboy. At low speeds in the traffic though, bit of a waste of time. And twice the movement = twice the time. You will always be able to downshift faster with one clutch-in than with two.

Keep in mind, that fast gearchanges are what ruin synchros. There's no reason synchros won't last the life of the car if the gearbox has been shifted slowly and nicely all the time. They are designed to bring the rest of the gearbox speed up to that of the mainshaft so the dog teeth of the gear will slot into place, selecting the gear. You shorten the time it needs to do this and it will wear faster.

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