Rev matching on a 350z

[Scallywag]

Hi all,

 

Please bare with me as I'm a noob to Nissan (I hear you all sigh lol)

 

I'm about to take ownership of a lovely looking bright yellow GT4 with the factory fitted Nismo kit & have been getting up to date with the lingo & what not.

 

I've only just realised that 'Up Rev' is not the same as 'Rev matching' - D'oh!

 

So, turns out i belive mine is an up rev engine as the red line starts at 7,000rpm & is the 300hp model due to being GT4 - but still in the lower tax bracket - also only covered 36k miles - Happy me

 

But would just like to ask please if there is a way to make the 350 rev match like the 370 does?

 

Cheers,

 

Scallywag

[Ekona]

Yes, you use your right foot and blip the throttle yourself

[Scallywag]

Haha indeed!

but I just wondered if there was such a mod for the 350?

ty

[Ekona]

There isn't, no. Tbh it would take some proper computer and sensory wizardry to make it work anyway, so would be more than the cost of the car to do. Besides, it's much more fun and satisfying to do it yourself.

[BobbyZ]

It actually annoys me a bit that they introduced the throttle blip thing on the 370z. A manual transmission should be exactly that IMO, matching of revs included.

 

Scallywag, get yourself a Nismo 380RS Accelerator Pedal, which will make heel and toe downshifts easier

[evilscorp]

Rev-up, not up rev, as the latter is a tuning software we use on our engines.

[Karl92]

just heel toe on the downshift like above the 380rs pedal makes this a little easier

[Stutopia]

It actually annoys me a bit that they introduced the throttle blip thing on the 370z. A manual transmission should be exactly that IMO, matching of revs included.

 

Scallywag, get yourself a Nismo 380RS Accelerator Pedal, which will make heel and toe downshifts easier

 

You can switch it off on the 70 though, can't you?

[Husky]

It actually annoys me a bit that they introduced the throttle blip thing on the 370z. A manual transmission should be exactly that IMO, matching of revs included.

 

Scallywag, get yourself a Nismo 380RS Accelerator Pedal, which will make heel and toe downshifts easier

 

The 370z uses the same transmission as the 350z, the 6-speed FS6R31A manual. The 350z quite nicely proved that the syncromesh within that box is made of cheap chocolate and will easily die off if not treated with care. The rev matching is a function added to give the gearbox an easier time by protecting it from poor driving and thus last longer. It's been marketed as a feature even though it is a sticking plaster over a problem.

 

All my own opinion of course but it seems highly likely to be the case.

[Ekona]

*rant*

 

This rev matching thing is doing my nut in now. I don't have an issue with it existing, and on the 370 you can at least turn it off, but now other manufacturers are in on it. Porsche, for example, have this in their sports cars now but it only comes in when you turn on Sport mode. Fine, no problems there. However, if you want Sport mode (so sharper throttle, looser TCS limits) you have to have the revmatch on, even if you don't want it! Only way to turn it off in Sport? Turn ALL the TCS systems off completely. Utterly ridiculous.

 

*/rant*

[Husky]

but it only comes in when you turn on Sport mode.

 

Wow, that seems extremely backwards

[Ekona]

It's retarded.

[brillomaster]

that's does seem incredibly annoying - given how much computing power cars have these days and that pretty much every car has an on board computer, I don't see any reason why all cars don't have a manual mode, where all the settings can be individually set up by the driver. by all means have a few presets as well, but forcing you to have rev matching when sport mode is on is just retarded.

 

its often confused me why auto gearboxes don't allow you to set upper and lower rev limits, when i'd thought it quite an easy thing to do. for example, when doing spirited driving, and I brake hard for a corner, the gearbox will hold 4th as I brake, then only downshift when I exit the corner and put my foot down. would be really beneficial if it had a minimum rev of 2500rpm, say, so it would automatically start downshifting as i'm braking so i'm in the right gear when I exit the corner.

 

even more stupidly, is that I know autos prevent engine damage by not downshifting if it would overrev the engine, but it really irks me that if I need a bit more power to make an overtake when the car is cold it'll happily take the engine to the redline when the engine is cold, when it seems such a simple thing to limit the revs until the engine is up to temperature. Theres only one car I can think of that has a redline that increases as the engine warms up (BMW E46 M3), would have thought on performance motors it should be more commonplace.

[Ekona]

even more stupidly, is that I know autos prevent engine damage by not downshifting if it would overrev the engine, but it really irks me that if I need a bit more power to make an overtake when the car is cold it'll happily take the engine to the redline when the engine is cold, when it seems such a simple thing to limit the revs until the engine is up to temperature.

They do, it's called your right foot

 

My Bummer also has the reduced rev limit thing. No idea if it's an actual limiter mind, because there's no way I'm going to thrash a cold engine just to find out.

[brillomaster]

PS if I ever get a 370z or a Porsche with rev matching I will be making use of the facility - plenty of times i'd have loved to bang in a few perfectly blipped downshifts, but my mechanical sympathy and fear of getting it wrong would normally prevent me from doing it too fast. even with plenty of track experience of heel and toeing I can't get it right every time, would be nice to have the ability to do it perfectly every time even if i'm just driving to work and brain isn't fully engaged yet.

[brillomaster]

even more stupidly, is that I know autos prevent engine damage by not downshifting if it would overrev the engine, but it really irks me that if I need a bit more power to make an overtake when the car is cold it'll happily take the engine to the redline when the engine is cold, when it seems such a simple thing to limit the revs until the engine is up to temperature.

They do, it's called your right foot

 

 

My Bummer also has the reduced rev limit thing. No idea if it's an actual limiter mind, because there's no way I'm going to thrash a cold engine just to find out.

 

its harder than you might think! been driving auto for nearly a year now, and still not confident on how hard to press the throttle to get it to kick down a single gear. often I'll sit there slowly applying more and more throttle until it kicks down, then immediately lifting off to stop it kicking down again. Heaven forbid you use the kick down switch (4th to 1st gear at 30mph anyone?!?)

 

most of the time these days i'm in manual mode with the paddles, but since manual mode is an extension of sport mode, you have the violent gearchanges even when you're pottering around town... why cant I have manual control, but soft shifts?

 

might just have to go back to manual!

 

Edited April 11, 2016 by brillomaster

[Ekona]

Well, it's what all the cool kids do

[brillomaster]

this is true... I find myself apologising for my lurchy automatic gearbox far more than I did when I was driving a manual! anywhos, once the wife replaces her aging 3 door hatch with a slightly larger 5 door hatch, i'll chop in the beemer and get a 370z.

[Husky]

that's does seem incredibly annoying - given how much computing power cars have these days and that pretty much every car has an on board computer, I don't see any reason why all cars don't have a manual mode, where all the settings can be individually set up by the driver. by all means have a few presets as well, but forcing you to have rev matching when sport mode is on is just retarded.

 

its often confused me why auto gearboxes don't allow you to set upper and lower rev limits, when i'd thought it quite an easy thing to do. for example, when doing spirited driving, and I brake hard for a corner, the gearbox will hold 4th as I brake, then only downshift when I exit the corner and put my foot down. would be really beneficial if it had a minimum rev of 2500rpm, say, so it would automatically start downshifting as i'm braking so i'm in the right gear when I exit the corner.

 

even more stupidly, is that I know autos prevent engine damage by not downshifting if it would overrev the engine, but it really irks me that if I need a bit more power to make an overtake when the car is cold it'll happily take the engine to the redline when the engine is cold, when it seems such a simple thing to limit the revs until the engine is up to temperature. Theres only one car I can think of that has a redline that increases as the engine warms up (BMW E46 M3), would have thought on performance motors it should be more commonplace.

 

If only auto transmission controls was that simple It's what I do for a living and yes, your ideas are great, however it isn't as simple to get the implemented. First off you have to remember that you are the 1% (if that) of the user base that would expect, want or even use the functionality, that alone is idea practically dead in the starting blocks. None of them relate to safety, in fact they may introduce a higher factor of risk to the transmission by their implementation, that's another road block as you'd have to do a full hazard and risk analysis of each one. You have to answer questions about what setting limits would do in every conceivable situation, would it endanger the driver or others? you get the idea.

 

You have to tune everything and you have to do it for every variant of the car. If I use that gearbox in 4 different vehicles I make, I have say 3 engines for them, each engine has 2 power variants, then I have an AWD option in 25% of the options available. That's 4x3x2 = 24 plus the AWD = 30. All of a sudden you've gone up to calibrating for 30 different vehicles and that is a monster amount of work.

 

A lot of sport modes do what you are describing though, you need to test drive the box you are going to buy as they all have their own nuanced behaviours that you may or may not like. Something like holding a gear while in sport is common.

 

In regards to the downshift while you are braking, that's a huge big ask right there. The driver expects an amount of brake to give an amount of deceleration, if you down shift during that you are going to decelerate the vehicle more than expected. So your choice is; do you release the brake electronically in proportion to the expected deceleration of the vehicle due to driveline drag? or do you increase the virtual throttle pedal to negate the driveline drag, this means you have to be constantly changing the virtual pedal in relation to braking, vehicle speed and engine speed. Across 30 variants to calibrate... Big job right there.

 

The prevent downshift when cold is somehting that could be put in, but that would require the EMS to have a signal telling the Trans that it's in cold mode, and then the transmission would have to react to that. So the transmission guys need to agree with the engine guys to use the signal, the signal needs to be signed off for the correct safety rating, then they can crack on and make the functionality, but wait, they dont actually make the gearbox or the code... So they need to build a set of requirements that they send to the gearbox supplier, the supplier charges them a fortune and develops the functionality for them. After they get the new stuff from the supplier they then need to test that all their requirements have been met and the software doesn't do anything funky, it's an iterative process if faults are found.

 

The car isn't one big computer, it's 100. Those 100 computers have tens of thousands of signals. It's a massively complex system that has major safety implications if done wrong, so we only do things if we can justify the feature and it's cost.

[Ekona]

And that, ladies and gents, is why the manual is the best option bar none.

[BobbyZ]

It actually annoys me a bit that they introduced the throttle blip thing on the 370z. A manual transmission should be exactly that IMO, matching of revs included.

 

Scallywag, get yourself a Nismo 380RS Accelerator Pedal, which will make heel and toe downshifts easier

 

The 370z uses the same transmission as the 350z, the 6-speed FS6R31A manual. The 350z quite nicely proved that the syncromesh within that box is made of cheap chocolate and will easily die off if not treated with care. The rev matching is a function added to give the gearbox an easier time by protecting it from poor driving and thus last longer. It's been marketed as a feature even though it is a sticking plaster over a problem.

 

All my own opinion of course but it seems highly likely to be the case.

 

Important part in bold

[brillomaster]

to be honest it wasn't the automatic feature that made me pick the gearbox, it was the flappy paddles... which in fairness work pretty well. upshifts are quick as are downshifts... easy to push the paddle twice and drop two cogs whilst braking for a corner, and foot flat flappy paddle upshifts are quite entertaining.

 

and now I've got used to it a bit more I can call downshifts on demand with the paddles when in auto mode, which stops the car lurching forward when using the pedal kickdown.

 

 

 

 

[Scallywag]

Thanks for all the info guys

[brillomaster]

sorry thread hijacked a bit there! but with regards to rev matching, practice makes perfect if you dont have a computer to do it for you