Jump to content
SAU Community

Recommended Posts

I know the switch will force the car to start in second, but what behaviour does it cause after that.

I found some documentation on the Subaru 4EAT (which is also made by JatCo, same as the Nissan boxes) that states that hold+2 will be permanent second, hold+3 will start in second, change up to 3rd as soon as possible and then basically stay there, and hold+d will start in second then drive normally other than not using 1st.

Is this also true for the A31's gearbox?

I'm asking mainly because I'm interested in taking the car on a dyno and if the Nissan box does behave in that way, it should be pretty easy to get meaningful figures.

Don't think it forces higher gear starts.

The switch dictates where the gearbox shifts under normal driving.

If its on hold it'll shift earlier than normal, if the switch is off it'll shift whenever, if it's on Power it'll shift as late as possible but won't exceed the redline.

If the switch is on hold or neither, and you plant your foot, it will act as Power anyway and shift late.

The idea of the switch is to change the shifting behaviour between cruising and hard driving, but it makes little difference.

serious? it makes HUGE difference... it's also known as "snow" switch...

basically in less than desirable weather ie: rain you flick the hold switch... car starts in second and configures the gears to keep low rev range, high torque, low power... so that the wheels don't spin and you don't lose control so easilly

it's basically an ancient form of traction control

Yes, I've used it in the snow to good effect but never really knew how it actually worked. Only problem I had in the snow was dealing with other people's stupidity, oh and finding out that the font diff is open thus managing to get stuck out in the Brecons with 3 wheels spinning and one still.

So will the switch be any use for getting a meaningful dyno run or not. Don't want to waste £60 if they can't get it to stay in one gear for most of the run.

The only 4WD dyno that I can reasonably get to doesn't seem to think it's possible to dyno an auto as they can't control when it changes gear, resulting in a meaningless gear.

I'm just trying to find a way to make it a bit easier for them.

^^^was gonna say this but wasn't sure if it'd insult your intellect

you could also unplug the solenoid / fuse that controls power going to the front wheels too making it RWD only and just do an RWD dyno

wait a minute 4wd isn't the problem

well yeah you cant hold the gear like nic said

its a 3 speed auto, which means there's 3 gear ratios to operate the car in.

Hold affects the point at which the gear ratio is changed, as does power.

The only thing that might affect the ratio is overdrive, which it should automatically switch to after about 60 km/h or thereabouts. This is kinda like 3.5.

Summary: Leave it in "Drive" and turn off "Overdrive". You will end up in 3rd gear at higher speeds. Dyno.

I beleive late models used the 5 speed auto....not sure on AWD though ?

I know all the turbo auto's were 5 speed

all turbo's come with a "4 speed auto", which is 3 forward gear ratios and a reverse.

n/a's came in a 5 speed at the end of production, when they introduced a 2.5L n/a.

Mine's a 4 speed which may or may not be implemented as a 3 speed plus overdrive. The gearlever would imply that, but it could just be they didn't want to confuse people by changing it to D321. It's the same box as fitted to S13s

Would be interested to know what you do to force it into 3rd, well other than knacker it enough that it goes into limp home mode I mean.

I'd love to give you the answer but I honestly can't remember :ermm: it may have been R32 specific as well. Perhaps the easiest way is simply to PM 'URAS' :P.

Basically.. you can just drive it up to 80 with overdrive off and then use the throttle carefully.. but as pointed out it gives a pretty crappy dyno run and wont really show you anything. The OP I believe is asking how to lock it into 1:1 so that they can tune it.

As I said.. one of the fuses from memory will force the gearbox to stay in 3rd (or 1:1).

there is a bunch of plugs in the front left side down a little disconnect the brown plug will lock it in 3rd for dyno run so it dont kick back to 2nd

hope this helps

Edited by R334door(s2)

technically overdrive isn't a gear in itself. it's a modifier on the 3rd gear. But for the purposes of a dyno, it should be left off to be a 1:1 ratio.

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

    • He obviously had his reason for flipping you off. I wonder what it was...
    • Thats why I stay far, far away from Eastwood. only go there if I wanna eat Korean food 
    • I have to agree like, yesterday, I was driving down the warringah freeway towards the bridge when this jackass driving a beaten up Honda civic cut me off so suddenly it made me almost yank the wheel to avoid him hitting my car. Honestly and he had the NERVE to flip me off (or some other gesture Idk). Im a calm guy, but really some people just dont deserve to have a license, let alone be allowed to drive on densely populated roads/highways. If youre gonna cut through lanes at least use the damn turn signal
    • HPA do an interesting video on tuning, and Adrian shows on the dyno, moving from 10:1 to 12:1 (And I think even 13:1) and the power moves SFA. However, a couple of degrees of timing has a HUGE impact. Exhaust side of things will more be the length of the exhaust and how many bends and turns you have. The straighter you can keep it, the better. By a lot. Oh, and getting the diameter right. Bigger isn't always better. Going to big can actually lose you power.
    • I have to say, most people I see on the road fit the bill of atrocious drivers. Whether they be cowboys in their dual cabs, bogans in the Commodores, or the soccer mums. Pretty much most people on the road put zero freaking thought into driving. Barely look further up the road then the end of their bonnet, and have never even thought about how catastrophically wrong shit can go, by doing what they all deem as normal driving. Especially their late braking, racing to stopped lights, and sitting half a foot off the bumper of the car in front at 110km/h. Wanna know what's even better? By the time their kids get to be old enough to learn to drive, they've already got in the back of their brain what is normal driving, how annoyed you're allowed to get at people etc, and then their parents who actually have zero freaking skill at driving (Even though they constantly say "I've been driving for 20 years and never had an accident!") teach the little twerps how to drive, or should I say, how to make a car move. Literally watched a parent teach their L Plater, on a 4 lane freeway, that you just slam the brakes on, and push your way over, even with a B Double bearing down on you, and that's how you should drive, rather then, just keep going to the next exit. Same shit happens all the time for side streets etc, watching numpties pull dumb shit turns pushing across 3 lanes of traffic, rather than just go up the road another 30 seconds, and take the next turn that'll get you to the same location... Oh, and the damn right lane bandits. Or the retards driving along with their headphones in, and can't hear the ambulance or fire truck right up their ass about to run them over...   Pretty much, people drive on the road, like ego centric f**ks, and don't actually think how dumb shit their driving is, how it could easily kill them or someone else in a split second, or at the very least, how they're driving is contributing to all the shit they're bitching about on the road, like shitty congestion!
×
×
  • Create New...