Jump to content
SAU Community

Recommended Posts

Just saw these starting to pop up on IM over the last couple of weeks.

Don't really see much of a point to them, unless you cannot control your right foot properly.

my problem is takeoff.e.g. My mates EVO9.....standing start he puts 5-6 car lengths on me....rolling start from about 20-30km's I put 1 on him......just takes to long to get going.

Edited by Jetwreck
my problem is takeoff.e.g. My mates EVO9.....standing start he puts 5-6 car lengths on me....rolling start from about 20-30km's I put 1 on him......just takes to long to get going.

Put a pianola on his room and see how he goes!

IMO you should wait for the ECU, then if you still can't get him, no harm in trying one. (should smash him though)

Have you got an electronic boost controller? Is the mechanical end of your throttle properly adjusted? Try launching with 5000rev/min (left foot on the brake until takeoff).

No boost controller.....running the standard 14-15psi......Mechanical is good....Yeh used to be able to do that with the standard turbo....new one wont let me.

The point of the electronic boost controller is not necessarily to get more boost but to build boost more quickly and to maintain boost at the top end.

Jets new turbo should boost up pretty quickly and hold max boost to redline all on it's own (I know that my hiflow does :D ).

Edited by iamhe77

These are actually quite interesting and the features are available on some cars as OEM features.

For example, on my wife's SAAB 9-5, when you press the Sport button on the gear shift, not only does it select a more agressive program for the transmission, but also for the drive by wire throttle, with a much smaller pedal movement leading to full opening of the throttle. This really does make the car feel much more spritely, but it also increases the fuel consumption quite dramatically....

Lots of other Euro's have this as well.

Going the other way, Landrovers have the opposite. When low ratio is selected a much less sensitive throttle map is applied to that if the pedal is accidently floored, because you hit a bump when off roading, it does not apply the entire V8 supercharged grunt. Should the throttle be held to the floor, rather then just jabbed, then the requested power will be applied to the wheels..

been looking into manufacturers that make it

those things are brilliant..

they work really well

fly by wire cars have really slow response in throttle..

it's not the matter of controlling your right foot.

a mate of mine put 1 of these things (from toms) the difference it made to the car was amazing.

the repsonse of the throttle imporved sharply

Edited by [[d a n n y]]

If I understand correctly, this doesn't actually give you anything that you couldn't simulate with your right foot, but it just allows you to adjust how far the throttle will be open vs how far the accelerator is pressed down.

In one sense, the sport mode could then be similar to putting your foot down faster on the throttle, reaching full throttle sooner.

Looking at the graphs, it still will not reach full throttle until the pedal is all the way in, but the difference in throttle position between 90% and 100% pedal is much less than without the gadget.

My first thoughts are, for "sports" mode, couldn't you just drive more aggressively? and my concern for eco mode, is that eventually I would "learn" the new pedal feel and my fuel economy would return to normal, due to me using much heavier throttle to compensate...which would then prove troublesome if I were to switch to sport mode after driving in eco mode for weeks.

As for any delay with the drive-by-wire setup, this will still exist because you're not removing anything from the system. The unit just slots in between the pedal and the ecu so any lag that was there before will still be there afterwards.

It looks like a very simple unit that changes the voltage measured from the pedal so that rather than being a straight line graph it becomes a curve. The different modes it offers are just adjustments to this curve.

Any further thoughts on this?

Another thing I was thinking is: how does the ECU handle gear shifts? is this based on pedal position also?

If I understand correctly, this doesn't actually give you anything that you couldn't simulate with your right foot, but it just allows you to adjust how far the throttle will be open vs how far the accelerator is pressed down.

Problem is how quickly the throttle opens.... unfortunately with drive by wire you don't always have complete control over this.....with the VQ25det if you step on it from a standing start the throttle opens very slowly....you are better with a slow squeeze of the peddle....while the car is in motion the power is fine and has hardly any lag, goes like shit off a stick....It's just getting it going from standstill thats the problem.

Problem is how quickly the throttle opens.... unfortunately with drive by wire you don't always have complete control over this.....with the VQ25det if you step on it from a standing start the throttle opens very slowly....you are better with a slow squeeze of the peddle....while the car is in motion the power is fine and has hardly any lag, goes like shit off a stick....It's just getting it going from standstill thats the problem.

I do agree but I'm still failing to see how this unit would help. The ecu is going to read either the signal from the pedal (unmodified) or what this unit changes it to. In either case, the maximum pedal amount is still 100% in either case, so for example slamming the pedal to the floor would acheive exactly the same result either way. Its the ECU that decides how much to open the throttle, and this unit is not bypassing the ecu, so it will have the same limitations as the standard setup.

Hope this makes sense? I just dont think its possible to improve the lag situation without bypassing the ecu altogether - which is not likely to be possible or practical.

In a lot of ways I would have preferred if Nissan had still used a cable instead of going with drive-by-wire, since I think the drive-by-wire system seems to have an ever-so-slight delay in responding to pedal movements, especially when the movements are only small. However there are advantages to drive-by-wire (so they tell us). I think it helps the engine to maximise torque when accelerating ?? and it probably helps with fuel economy somehow too...

Personally I find the acceleration to be at its peak in 2nd and 3rd gear, so the acceleration from standing start may have more to do with the gearing than the pedal. The same goes for the lag in any driving situation...whatever communication and logic that goes on between the ecu and the gearbox - I'd love to speed that along a tad. The engine is always ready to take off in its usual ferocity but the gearbox is always a bit over-cautious. When the two are in harmony the acceleration is awesome, but when they're fighting each other it can be frustrating, like there's a secret argument going on and you're the innocent 3rd party that just has to wait and see what the outcome is.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • So..... it's going to be a heater hose or other coolant hose at the rear of the head/plenum. Or it's going to be one of the welch plugs on the back of the motor, which is a motor out thing to fix.
    • The oil pressure sensor for logging, does it happen to be the one that was slowly breaking out of the oil block? If it is,I would be ignoring your logs. You had a leak at the sensor which would mean it can't read accurately. It's a small hole at the sensor, and you had a small hole just before it, meaning you could have lost significant pressure reading.   As for brakes, if it's just fluid getting old, you won't necessarily end up with air sitting in the line. Bleed a shit tonne of fluid through so you effectively replace it and go again. Oh and, pay close attention to the pressure gauge while on track!
    • I don't know it is due to that. It could just be due to load on track being more than a dyno. But it would be nice to rule it out. We're talking a fraction of a second of pulling ~1 degree of timing. So it's not a lot, but I'd rather it be 0... Thicker oil isn't really a "bandaid" if it's oil that is going to run at 125C, is it? It will be thicker at 100 and thus at 125, where the 40 weight may not be as thick as one may like for that use. I already have a big pump that has been ported. They (They in this instance being the guy that built my heads) port them so they flow more at lower RPM but have a bypass spring that I believe is ~70psi. I have seen 70psi of oil pressure up top in the past, before I knew I had this leak. I have a 25 row oil cooler that takes up all the space in the driver side guard. It is interesting that GM themselves recommend 0-30 oil for their Vette applications. Unless you take it to the track where the official word is to put 20-50w oil in there, then take that back out after your track day is done and return to 0-30.
    • Nice, looks great. Nice work getting the factory parts also. Never know when you'll need them.
    • Thanks @jtha7 I will have a look around tomorrow but it is a prick of a spot. These are some photos i tried taking 
×
×
  • Create New...