Jump to content
SAU Community

Recommended Posts

Ok, thought i would start a discussion on the auto trans, get a good discussion going.

Some discussion points, of which some are questions from me are

- What power is the box good for

- What upgrades can i do, apart from valve body?

- Torque converter, whats the deal? Replacing it and so on (i want to replace mine)

- Stall converter kit? Does anything exist?

- Is there any addon where i can give my car tiptronic style gear changes on my S1? Basically make it a clutchless manual style thing?

Anyone that can answer, cheers.

Link to comment
https://www.sau.com.au/forums/topic/102861-automatic-trans-thread/
Share on other sites

  AlexCim said:
Ok, thought i would start a discussion on the auto trans, get a good discussion going.

Some discussion points, of which some are questions from me are

- What power is the box good for

- What upgrades can i do, apart from valve body?

- Torque converter, whats the deal? Replacing it and so on (i want to replace mine)

- Stall converter kit? Does anything exist?

- Is there any addon where i can give my car tiptronic style gear changes on my S1? Basically make it a clutchless manual style thing?

Anyone that can answer, cheers.

so u have made up your mind or still deciding? (auto vs manual that is) :)

Well, ive made my mind up.

The reasons i am keeping the auto is

- I want to tow things, with the clutch i would want it wouldnt be fun!

- 7k can be spent on other mods, which i CAN remove when selling the car. Meaning i wont loose THAT much money. Meaning i get other mods sooner too.

- The money i save on the conversion, i can put towards importing something like a 7k non regoed, non complied race/drift silvia/GTST.

If i can build the auto to be quick shifting, responsive, tough, hard launching and if i can somehow get it to work tiptronically style, that would be best. All i really hate about the auto is f**king kick down.... but ill deal with it.

Many people have two cars, i am sure i can do that too...

2 cars & a bike, absolute bliss. *wink*

Yeah, I too would like to 'convert' to tiptronic style. Dont know how or if it could be done, 1st thing though will be to do the actuator valve body exchange and add a big oil cooler kit.

What do torque converters do, and are they worthwhile for a 200awkw auto Stagea thats primarily a family car?

I am far from an auto box expert, I leave that to the profesionals. The following assumes some level of knowledge of how an automativc geabox works. If you don't know, then this is the best thread I have seen for a while, please read it first;

http://www.ukcar.com/features/tech/gearbox/AUTO/

The auto in a Stagea is made by Jatco, and is basically the same as Z32 and R33GTST (+ a 4wd transfer case bolted on the side) and several other larger 6 cylinder Nissans, 4wd's, utes, trucks etc. So parts and knowledge are not hard to find.

If you need higher rpm for launch (so you have boost) then a high stall speed torque converter is the answer. You pick the stall rpm to suite the boost build characteristics of the turbo. The standard torque converter has around a 2,000 rpm stall speed, but as you increase the torque output from the engine the stall speed climbs a bit. At around 150 rwkw mine was at 2,250 rpm. Since you have the engine producing kinetic energy and the car going nowhere this energy has to be converted (Newtons Law, see, high school physics is sometimes usefull), in this case into heat. Think 60 or 70 of those 1 kw bar heaters, that's a lot of heat. That heat goes into the transmission fluid, hence the need for a big tranmission cooler.

An example, if you have turbo that produce boost at 3,500 rpm then you get a 3,500 rpm stall conveter. Bingo, boost at launch. The problem is (you get nothing for nothing) it is always a 3,500 rpm stall torque converter, so the car won't move until the engine is doing pretty much 3,500 rpm. That's bad for economy, emmisions etc

The Stagea auto uses a band for 2nd gear engagement, this can be upgraded with a stronger band (sometimes kevlar) which gives higher grip (to handle the extra torque) and tolerates more slip and heat.

The 3rd and 4th gears are engaged by clutches (wet clutches, like the ATTESSA), these can also be upgraded to handle the extra torque.

The bands and clutches are controlled by valves switching hydraulic pressure, so a "valve body" upgrade can be used to speed up the band/clutch engagement (sometimes called a "quick shift kit"). This lessens the wear on the bands/clutches and makes the gear change quicker/sharper. As usual you get nothing for nothing, this means slightly harsher gearchanges, not as seamless, less smoooooth. Good oil temperature control is necessary for tight gearchanges, hence the need for a big transmission cooler.

How much does it cost? Well the full upgrade (torque converter, bands, clutches and valve body) seems to be around $3,500 (excluding gearbox R&R). The first step is a big tranmission cooler (~$200), then a valve body upgrade (~$300), then its inside the gearbox time.

How much power will it handle? Damn tuff to answer as the weight of the car and its traction (Stagea = 4wd and 1700 kgs) has some bearing. It will most certainly handle as much as the standard engine internals are capable of supporting (ie; ~300 rwkw).

That's about the limit of my research so far, hope it was of some help. MV Automatics in Adelaide seem to be the Skyline auto experts. There was a valve body exchange arranged on the Group Buy section a while ago with them.

:) cheers :D

Edited by Sydneykid
  • Thanks 1

Yeah, thanks heaps SK, very VERY helpful info. MV Automatics charge around that $500 mark for supply only of valve body (exchange) & big oil cooler, or around $650 fitted for me (just up the road).

Now I understand a stall converter; so you dont move until it's 'stalled up' as such. Certainly not necessary for a family-type car, for me anyways.

With the valve body upgrade, Ive been told by SA forum members who use the product that the shifts are as harsh as how far your right foot is down on the throttle. City easy driving and its not too harsh, flat stick 6000rpm change and it'll bang up into the next gear......

Thanks very much for your input SydneyKid, appreciated.

Brendan

  sy300 said:
Has anyone got photos of the standard cooler vs upgraded?

I was interested in seeing the actual size difference.

It's not just size but the fluid flow though the cooler that's important.

TransCoolerComparisonSmall.jpg

I started a thread a year or so ago on transmission coolers, if you need to know

any more details this is the link;

http://www.skylinesaustralia.com/forums/in...showtopic=59399

:) cheers :)

  • 4 months later...

One other thing though Gary, what about the lock up clutch in the converter.... i was going to see how high Mike could make one and still keep the lock up part, so cruise and highway didnt suffer with excess slip. I really need one to help with the sprint racing.

Gary

for $3500 for the upgrade, it's coming on par with my current spending for manualisation. mine will roughly come to $4000 after install (not including powerfc and hiflo turbo)

so it doesn't really matter which avenue you take, but you get a superior results afterwards.

  • 2 years later...
  • 4 years later...
  • 2 years later...
  • 1 month later...

Sorry to drag up an old thread - I have searched honest!

Has anyone upgraded the belt and clutch packs? Anyone know of any decent suppliers of kevlar etc? Going to have the box out to fit a transgo kit so might as well get everything upgraded while its out.

Are the clutch packs different from different cars - I.e. would the ones from a patrol be any stronger, or are there aftermarket ones?

I'm not after mental power from the engine, would just rather do things once.

(S1 re4r01a)

Ta!

Mowgs

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

    • Seat of the pants assessment of the new intake: The car is way less "doughy" when hitting the loud pedal, especially off idle when stopped or in traffic, I did use a cheapo lazer thermal thingo to measure the temp around where the pod filter got its air, it was between 55 - 60°C, in saying this the car was shut off and not moving, so the OEM intake pipe was not supplying any fresh air to where the pod was when the car was at least moving A weird bonus was induction noise on the throttle in the cabin increased a bit,  I was worried that I was actually going to lose some of that induction noise I love so much, outside though, when I got the daughter to do a WOT drive by pass for me, the induction noise has increased alot when on the throttle, not quite ITB doort, but well up there I'm extremely happy with the results and have been exploring the country roads in the region  As for house mods: 1.New front fence is up and is awesome, it really upgraded how the joint looks from the street, and the added security is nice 2. Electricians have replace some interior lights, and with more lighting in the garage, a few new motion detecting lights out the front above the garage, front room, and at the front door, which I have already found heaps helpful coming and going, also now has fancy pants CCTV all round the house The only hold point for power though is the solar and batteries due to supply issues, although this will happen over the next few weeks 3. I have done a heap of landscaping out the front and I'm almost ready to do a new small retaining wall with some nice blocks to replace the brick and cemented in rocks around the raised garden beds cemented in river stone "was the fashion at the time" the house was built. I currently have a pallet of retaining wall blocks and 2 bulka bags of 20mm blue metal to replace the wood chip that is in the raised garden beds around the house 4. I now have 3 big raised garden beds for out the back to grow some vegetables, about 70cm high, 200cm long and 100cm wide 5. My 2 compost bins are already pretty full with brown, green and kitchen waste from the landscaping I'vedone so far, but they will probably take a few months to break down, so anything else that gets chopped, trimmed, and kitchen waste will just start filling the base of the raised garden beds to about 30cm before I start throwing 40cm of good compost, and stuff, for the vegetables to grow in, I'll need a few ton of compost and soil, but the local supplier can sent me bulka bags of the stuff Basically the logs, wood chips and a few strategically placed rocks for drainage, will give the beds some good organic materials down low to break down over time, and they will hold moisture during the warmer months to save the water in my big arse water tank if we don't get alot of rain So, all in all, the car and house mods are going well, and I'm really enjoying being retired, I sleep in too 0700 and slowly plod around inside until I feel like actually doing anything, and only work in the yard for as long as want, which has actually been alot over the last few weeks,  although when you look at it, it seems that not a huge amount of work has been done,  until I look at the before I started the work pics Happy days and good times indeed 
    • hahaha yeah. Plan is to get side skirts and probably just rear pods. But going to do them one-by-one. I've got a set that I really like from RHDJapen, but that one isn't shipped to AU. So need to find someone who can get it for me
    • Here's an idea, answer the questions I asked you as they are trying to work out WHY the LSD will be binding up in a straight line.
    • You haven't driven many modern cars then have you? Most of them have sfa steering feel with their stupid electric bullshit steering systems.
×
×
  • Create New...