Stock AWD Territory zf6 trans power limit

[Puffwagon]

Hey guys, I know when they break from outright power, the input shaft lets go around 700awkw. Stock clutches can barely hang on when rolling into it while in gear at that power level.

What I'm after is the power level that they stop being able to shift at. My own stock trans stopped shifting properly at about 520awkw but I've learnt a bit more about trans tuning since then. Perhaps there's more I can learn and perhaps they can actually be made to shift at a higher power level?

I've got a guys awd territory here that is making about 550awkw and despite some pretty hectic numbers in the tune it is not very happy to shift through the gears. It will shift but the 3>4 shift is a bit slow.

 I have raised shift and line pressures, cut shift times, changed the amount of torque reduction on shifts, unlocked the converter, juggled the type of torque reduction and it will shift at WOT but it isn't particularly happy to do so.

While I do want to buy the zf6 trans manual at some stage, I also have had a timing chain tensioner failure with my own car which needs fixing. As is the way, I would have to choose one over the other so it leads me to asking the question.

I would just buy the zf training manual and perhaps find my answers there but I don't want to buy it now just to find out that there's nothing I can do to improve this guys trans. I do want to buy it sometime however, but I also have my own car to fix and that is fairly high on the list.

For reference my own awd territory makes 766awkw with a built box, and with the same style and level of tuning, I have that shifting through the gears no worries.

I guess what I'm asking is, am I pushing shit uphill at this power level with a stock trans?!

[Puffwagon]

Ok well being the impatient person that I am sometimes, I ordered and paid for the zf trans tuning guide. At least I will know that I've done everything I can for old mates trans tune and without sharing specifics, can update this thread on how much the stock awd TT trans can can handle on a shift.

[abs351]

Hi Puff,

I have been playing with variant parameters with the ZF on a TT and i find there is limitations along with the physical car with which doesn't help too.

Your question:

I guess what I'm asking is, am I pushing shit uphill at this power level with a stock trans?! Yes, with what power you are running! lol

Have you run a comparison value with the F6X trans parameters as a starting point to work with as a base.

here is an example between HACH3 (TT)and HACH4 (F6x)

HACH3 (TT)Strategy: 6R79-7J105-BD

HACH4 (F6x)Startegy:8R79-7J105-AA

Below are the variants between both.

 

Overall I'm sure you are a proficient tuner.. Be interesting what the user manual references too to help with survivability with the ZF on high power demands.

regards

Abs

 

[Puffwagon]

I haven't compared an f6x strategy but I'll have a look. Pressure wise this trans already has a lot more in it than a stock f6x and after I get to reading the manual, I think it will get a lot more too. I just didn't want to chuck 17 or 18 bar into it if it wasn't going to do anything or was going to damage it. I had 18 bar line pressure in my stock trans and it held on in gear at over 650awkw for ages so maybe it's the right move?

Hopefully I can sort something out, I'm confident I can get it done, if it's possible to do.

[abs351]

Yeah, I agree also with increased line pressure is the first measure for survivability. I also upped the line pressure on my tune to 17 bar and tapered off on 5-6 gears. I believe it's the right thing to do also (line pressure) as legacy trannies (HiPo C4's,C10's..ect) have this modification done on their valve body or valve pump to help with survivability but of course driving comfort is lost.

FYI, you may know already - HACH4A5 / 87AA is the F6X

 

Keep us posted if anything stands outs within the manual..

[Puffwagon]

I've also heard that the same pressure can be used with the upshift on a built trans. Mine doesn't use that much, it's around 10 bar for the upshift but has 17 bar line pressure in 3rd and 4th. I looked into what the American guys are doing with their 6r80's as they are more or less a zf6, most of them are running those kinds of pressures.

There is more to upshifting than just increasing the oncoming clutch tho, I've detailed a few other things I've done in the first post, I know there will be some info in the book for me regarding a few other parameters that I know need adjusting.

 

[BeerTurbo]

On 3/16/2023 at 10:20 AM, Puffwagon said:

I've got a guys awd territory here that is making about 550awkw and despite some pretty hectic numbers in the tune it is not very happy to shift through the gears. It will shift but the 3>4 shift is a bit slow.

on my r31 bf+t the trans will snap throught 1-2 and 2-3rd shifts but allways seems to mismatch the 4th shift. its verry frustrating as it will drop out of boost and lose wheel speed. id love to know if its possible to fast shift it. it is a na trans tho, might be hating life.

[Puffwagon]

My first post lists what you need to do to a trans, the manual points you in the right direction to make those changes. I did learn something new but it doesn't help with making a 3>4 shift at high load. I'd say that 450 to 500awkw is the limit for a trans to work properly and live longer than a few months.

@BeerTurbo Haha the one thing you are asking me is the one new thing I learnt and I had to pay for it lol. More than likely you can't get your trans to shift any better unless it gets upgraded clutches.