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Mines installed (has been for over a year now) and there is no change whatsoever in how or when the auto shifts...

 

What would you expect if it was screwing with the logic?  Harsh changes?  Holding gears too long?  Or something different?

The ECU retards the ignition on gearchanges to smooth out the change and take load (torque) off the gearbox while it changes ratios. This helps the gearbox last longer. If the logic for retarding the ignition gets screwed with, the upchanges become harsher (clunky) and you will get some flairing (rpm increase) during the upchange. Down change (kick down) is also harsher (jerky) and sudden. There should be no change in the rpm that gearchanges happen, either up or down. The gearbox oil temperature will increqase as well and it will need changing more often and when you do change it it will smell like burnt toast.

In theory the SITC should be OK. If you set the SITC to advance the ignition say 2 degrees at the shift rpm, the ECU will still retard the igntion the same number of degrees. It will just start 2 degrees more advanced and during the retard (gearchange) it will still be 2 degrees more advanced. This should be OK, but I have never personally tried am SITC on an auto. They work OK on manuals within the limits of their small number of load points (usuallly 5). The algorithm between those points is not teribly sophisticated compared to the later SAFC's which have great algorithms.

The EManage and similar later generation ignition timing changers, don't work like the SITC. They actually change the ignitiom timing to a programmed point, not move it a certain number of degrees like an SITC.

Hope that helps:cheers:

OK... I've driven an auto 33 with a "plugin" ( :P ) Wolf and the auto doesn't know when to change gears, and when it does change, it bangs into gear... I didn't get a chance to test it completly, but it's doesn't "feel" right at all in my opinion... My car exhibits none of those symptoms...

I suspect your theory is correct though... When wiring in the SITC, you cut the wires from the CAS, route the signal to the SITC device, and then back to the ECU... So as you say, your only adding or subtracting small amounts to / from the original readings... Not controlling the timing completly as you would with a full ECU...

I agree about the interpolation algorithms too... It's not too hard to confuse the poor thing... In the end, the SITC is just a basic sensor bender...

Thanks for the advice SK... :)

If the logic for retarding the ignition gets screwed with, the upchanges become harsher (clunky) and you will get some flairing (rpm increase) during  the upchange.

Does the SITC actually change anything though if its all zero'd out? Surely it would sit idle and all timing maps/gear change logic etc would run as if the sitc wasnt there?

If so, you could just set the main shift point.. say 7000rpm back to zero correction?

Thats if it creates a gear problem at all though.

Guess we will find out when its all together and ready for tuning :P

Hopefully theres no problems :)

Sorry to hijack your thread, but can someone confirm that the SAFC doesn't have AFM switching ability? I was planning on getting one to swap my stock CA AFM for an RB20 one. Does this mean I will need an SAFC2?

Also, has anyone got real world experience with injector substitution with and SAFC/SAFC2? Once again I was thinking of switching my 370cc injectors for 440cc GTR items, and haven't seen any hard evidence (people with cars using just SAFC/SAFC2) that they can perform this function succesfully.

Thanks in advance.

Does the SITC actually change anything though if its all zero'd out? Surely it would sit idle and all timing maps/gear change logic etc would run as if the sitc wasnt there?

If so, you could just set the main shift point.. say 7000rpm back to zero correction?

Thats if it creates a gear problem at all though.

Guess we will find out when its all together and ready for tuning :rofl:

Hopefully theres no problems  :P

I don't know about your auto, but my Stagea changes gear at 1,000 sometimes, 2,000 rpm somtimes, 3,000 sometimes etc depending on the load. the throttle position etc. It changes both up and down at all rpm's, it would be lucky to change gear once in 1,000 times at 7,000 rpm. That's why I need the basic shift logic to be working, so that i's good all the time.:D

I don't know about your auto, but my Stagea changes gear at 1,000 sometimes, 2,000 rpm somtimes, 3,000 sometimes etc depending on the load. the throttle position etc.  It changes both up and down at all rpm's, it would be lucky to change gear once in 1,000 times at 7,000 rpm.  That's why I need the basic shift logic to be working, so that i's good all the time.:(

Yeah mine does too ofcourse, but i was thinking that even if the logic is a little different, a change at 1000, 3000rpm etc wouldnt be effected as much?

The computer wouldnt retart timing at all for a normal low load 3000rpm change?

And if so, it would be very little i assume.

The main thing with this is so i dont have to cut all the piggybacks ive spent ages putting in, sell, add another $500 just to get a wolf, when wolf have problems with the R33 auto box anyway.

Im fairly sure ive got everything covered, its just tuning and compatibility issues to sort out. Aslong as the standard ECU can use the SAFC2 to control afr's and control the Z32 afm, and the SITC to keep timing in order as best that it can...

In your judgement, how do you think my setup will work with an aim of 250rwkw/1.2bar max?

I cant really see any other option with the intended setup, besides getting manual conversion and powerfc. And thats not happening.

There is a bloke in Adelaide running an Auto with a PowerFC.

 

He said it drives perfectly fine.

 

I've heard it booting along and it appears to change fine.

 

4DoorSleeper I think he is.

Yes but this seems to be a very rare if not one off thing.

If powerfc worked then ide be buying one in a second. But unfortunelately they dont :) So this is my best option to get what i want at the moment.

Ive had thoughts of selling and going manual but im not finished with this project yet, ide like to see it through, and see how it goes. Its run VERY well since ive owned it, never missed a beat, the engine and all its parts are in very good condition and is a good base for some power. Im a little bored with the 180rwkw it has now, but 250 should keep me happy for awhile :)

Then ill be moving onto bigger and better things, next time ill be starting with a faster car so its easier to make it go faster ;)

You will have to go manual eventually or spend $$ on building up a tough Nissan Patrol box as they can be installed with very few mods.

Apparently they run thicker input shaft and splines.

Notice the apparently's. haha :)

'Apparently' with a modified valve body the stock box will hold up to around 350kw's (unsure if that is rwkw or fwkw).

This mob have alot to do with the 4speed Patrol auto.

http://www.automatictransmission.com.au/default.asp

The following mob have also 'apparently' used the patrol box in hipo Skylines.

SA Race Transmissions and Differentials at Modbury North (SA).

14 Famechon Crescent

Modbury North SA 5092

(08) 83961688

I've toyed with the idea of a tough auto behind the rb30det.. :)

Really depends when it comes time to replace my 5speed witha rb25det item how much I'm up for inc. the clutch.

It may work out roughly the same $$ to get a decent auto that would be much quicker for my duty's.

But then I would miss out on playing down at Mallala.

EDIT: I'm going to give them a buzz and find out exactly what I'm up for and mods required.

Sorry for being off topic but it kind of is on topic :)

The PowerFC & Elec 4speed can work and has worked.

I will dig through the wiring diagrams and find out exactly what is different between the auto & manual.

Apparently the problem with the powerfc's etc is they don't send or have an output for the auto's tps requirement etc. Splicing in to the wiring is usually the way around it *sometimes*.

Patrol RE4 $4,000-$5,000

C4 $3,500-$4,000

Trimatic $3,500-$4,000

The Patrol box is the same as the skyline box but has bigger shafts etc, basically bigger every where. And it will hold 350rwkw for street duty's when rebuilt with valvebody etc.

The C4 & Trimatic are both full manual valve body's as obviously turbo doesn't have vacuum. :)

There is a bloke in Adelaide running an Auto with a PowerFC.

 

He said it drives perfectly fine.

 

I've heard it booting along and it appears to change fine.

 

4DoorSleeper I think he is.

As I have previously posted, I had a guy tell me his R33 GTST auto with aftermarket ECU was perfect. I got him to bring it over and took it for a drive, my opinion was it was CRAP. It hunted between gearchanges, was clunky, didn't kick down very fast, flared on upchanges and jerked badly on down changes etc etc. I took him for a ride in one with an SAFC only, which made similar power to his, and he changed his mind.

One man's food is another man's poison:cheers:

Sorry for being off topic but it kind of is on topic :)

 

The PowerFC & Elec 4speed can work and has worked.

 

I will dig through the wiring diagrams and find out exactly what is different between the auto & manual.

 

Apparently the problem with the powerfc's etc is they don't send or have an output for the auto's tps requirement etc. Splicing in to the wiring is usually the way around it *sometimes*.

The output from the Power FC to the Auto ECU is less than 1/2 of the problem. The main issue is the Power FC does not have any programming for ignition retard on gearchanges, like the standard ECU does. Speaking to the ECU gurus, they tell me that there is many times more lines of code in the auto shift logic program than there is in the fuel and ignition programming added together. And you can't fix that, well I can't anyway.

:)

I just realised that having to make a 35% reduction just to use the 550cc injectors only allows me actuall tuning of +-15% :Oops:

is this right?

i dont think thats enough of a tuning range to run a GT-RS at 1bar properly :confused:

not to mention the Z32 afm and weather or not it requires me to lean out aswell,

hopefully the z32 needs to be rich on all maps, that way they can cancell each other out a bit?

Robo,

Thats true but if you attach 550cc injectors you will have to lean out all the maps by say 35%. This only leaves 15% left from the origional 50%.

But the Z32 afm will pull out another 13% (guesstimate) from that 35% so I think it would work fairly well. :)

If it still runs rich turn up the boost :)

Robo,

But the Z32 afm will pull out another 13% (guesstimate) from that 35% so I think it would work fairly well. :D

 

If it still runs rich turn up the boost :)

So your saying the Z32 will require me to lean out 13% appox on top of the already 35% for the injectors?

:)

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