Xr6t 03 Ba Upgrade With Stock 4sp Auto

[xceptional]

Hi

Over the last few months, been having performance issues with the vehicle. Has been very under-powered especially under heavy acceleration. Have replaced the coils, plugs, fuel filter, strainer on the fuel pump in the tank but nothing helped. I did notice a rattle from the CAT which indicated to me the guts have come adrift and probably causing back pressure on the turbo etc.

I took the vehicle in for a dyno last week pinpoint the issue. The came back and advise that everything was pointing to the CAT. So they bored a hole in the CAT, removed the guts and closed it back up again. It seemed to have fixed the issue. Can't be certain as I was unable to take it for a spin.

So while I had the opportunity I asked them for the following mods:

Hi-flow CAT (larger and with about 2m of hi-flow piping after it till it splits up at the back)

Flasher2 upgrade with custom tune

Process West intercooler

The above alone will be approx $3k which I am happy to go with.

The custom tune was going to plan until they called up yesterday and said that they were not able to proceed as the wastegate actuator or something like that was peaking and could not cope with the higher flow from the turbo. Plus they said the injectors were not coping either as they were maxing out. These extras are going to be another $2k they quoted.

With all these mods, I can imagine them calling me back tomorrow and advising that the valve springs and fuel pump requires upgrading too to cope with the other mods (probably another $800 at least). When does this end, I was asking myself. Should they have told me before hand that these extra mods would be require? Could they reduce the boost/tune to not require the extra mods?

I didn't want to take the kw up to a point where other things may start going wrong I.e. bottom end failing, or of even more concern the auto dumping itself.

I am guessing that with all the mods above (should I go through with it) I should be seeing around 300rwkw or between 370 to 390 kw at the motor showing on the dyno chart. Would you agree?

If that's the case (and I have read quite widely around the forums) my stock auto tranny would be border line coping with that amount of torgue and kw or quite possibly munt it? I asked them if remaping the gear change timings with the edit would help. They said they wouldn't touch it as there have been some other places burnt by touching the gear change timings which has munted the tranny.

So, from the information I have gathered, and to clarify, is the best way to reduce any tranny damage with the least cost (as I will have spend quite a sum on the other mods) to:

1. Flush and replace the current ATF with Transmax Z or Penrite ATF synthetic including filter (to help reduce overheating)

2. Increase line pressure for firmer gear changes (to reduce slippage)

3. Change the gear shift changes with edit (to improve power to the ground)

Others have mentioned eliminating the S3 S4 & S5 solenoids. What does this this do and what is the cost? Still others recommend a transmission cooler, while other say flattening out the torque curve so as not to come on too hard early in the gear change.

Then there are others who have virtually done nothing to the tranny running at 300rwkw or above with no issues.

So the two most pressing questions are:

1. What sort of kw should I be expecting with the above mods (I.e. Hi-flow CAT with pipe, Flash with custom tune, Process West intercooler, uprated injectors, larger turbo wastegate actuator, upgraded fuel pump and valve springs) and is $5k to $6k a reasonable price for them?

2. Would the tranny survive such a dramatic increase in kw and torque and if not what's the most bang for buck solution to ensure it does?

I apologise for being so verbose. There is a lot to churn over and contemplate as you can appreciate there is quite a bit of $$$ being spent and I want to ensure I get bang for buck and spent wisely. It's my drive car not for dragging or for smok'n it up.

Thanks in advance for your valued expertise, experiences and opinions.

Cheers

[ravenhard]

man, long post...I had to get a coldie just to finish reading it...

answer to question 1, if its closer to $5k then yes its a good price. If its closer to $6k I would shop around. As you can see from my sig, I have done similar mods but have installed alot myself saving a little bit of install coin.

Answer to 2, I went from 205 to current level without much drama. Had the car for 5months since the work has been done. I thrash the sh*t out of my car without having done a single thing to the tranny. I have though started to save for a rebuild...the old saying you play, you pay.

[xceptional]

Thanks for the feedback ravenhard.

So you have not edited the gear changes timing or increased the line pressure? I'm starting to feel a little easier with the mods not overtaking the tranny now if that's the case. Do you have an intercooler as this seems to add the wicked low end torque that dismantles the tranny pretty quickly if not tuned correctly.

Cheers

[bluprinturbo]

if ive read this correctly your going to be charged 2 grand for actuator and injectors alone.if that's the case then they are ripping you off.3k for the cat, box/tune and pw cooler isnt bad,but 12psi actuator,which I presume theyd be fitting, and 968's or dekas installed shouldnt top 1k.dekas and actuator would be around 600 tops,so they want 1400 to fit.

[ravenhard]

to tell you the truth, I have no idea what they do with the tranny when they edit it. Never bothered me. They may have played with it, they may not have. I dont know. I did run a generic tune on it for a few weeks and I do know the shifts were horrible to the point I took off the generic tune I hated it that much, I didnt care that I was getting more power.

Just reading your post again, you said you got quoted $2k for a wastegate actuator installed and injectors installed. Seems dear to me. I searched high and wide when I got my work done. I got quoted $150 for actuator and $500 labour to install. Injectors I bought from a forum for $370 and my tuner installed them for $80. The price on the siemens have gone up but still in the last group buy they were $410. All up $1100 and that was from a forum sponsor not some backyard mechanic.

Edit: Beaten as I was typing slow.

Edited 07/12/08 10:45 AM by ravenhard

[JP300]

These cars have been out for a long time so if you go to a tuner/performance shop who has been working on these cars then they should have at least spoken to you of the potential additional requirements before they started the work.

There is always a cheaper option but just make sure that it is done properly the first time hence you will minimise the potential of ongoing headaches and expensive repairs.

As for the standard 4sp, I had my car running 305 rwkw for a year with no problems. That included a few visits to the quarter. I think this is a safe level for the 4sp autos. Once you go up over 320 - 340 rwkw then expect that it will not last. As mentioned, its the torque that kills autos.

[xceptional]

I will have to confirm the injectors and actuator. I was in the middle of doing something else and was not 100% concentrating. But you're right blueprinturbo the dekas are $450 on ebay and actuator - not sure what spec they are quoting but will confirm today.

Has anyone had issues with the stock tranny when you dump the slipper to change down to 3rd from fourth/overdrive? I have heard that the tranny does not handle the torque too well when changing to 3rd. They advise to use performance mode to change into 3rd before planting the foot, however, my bride often drives my car and she wouldn't really know when and what to do. She just dumps the peddle on the highway to pass or weave in and out of the traffic.

Cheers

[xceptional]

Confirmed what they were going to do. They were going to install a larger dump pipe with flap, port and actuator to handle the extra flow. They said this will be about $1,100. Does that sound right?

Cheers

[NVT]

xceptional,

I'm in the same boat as you are mate. I have a 2004 BA MK I XR6T that I have started modding.

It is very hard to find a stopping point once you begin modding, and the only things limiting this will be your wallet, how much the car can take before things start breaking, and how much power you want.

Have a goal - first and foremost - You have to! Otherwise you'll be lost mate... And it will spin out of control. Upgrade laer if you want, but don't go in blind...

In regards to the injectors - you will need a new fuel pump mate.

I got quoted $570 for flow matched 60lb dekkas installed which I think is quite good. Fuel pump is about $300 installed. A flash tune should cost you between $600 and $800 if you already have a box.

That's $1670 max for these 3 things. Then $1100 for your dump, wastegate etc.

I'm looking at about 270/280rwkw with a CAI, injectors, fuel pump, flash tune and cat-back exhaust. Much more than this, and your valve springs will crap out and your tranny will suffer. (Possibly valves at a lower rwkw...Budget for these as well)

In regards to your missus, anytime you accelerate hard, push it into Perf. I use perf up hills as well mate, seems to want to race up the hill )

Hope this all helps mate,

All the best with everything,

Dan

[400KwXr6t]

In regards to putting the boot in when in 4th my advise is Don't with a capital Don't. My 4 speed went Ka-blammo last year running bout 300rwkw

and the thing that went was the overdrive shaft.

Which in turn spits little nasty bits of metal through everything! Result 3K worth of rebuild. and that was a modded box. And I wasnt thrashing it (which the misseds fails to believe).

After crying and talking to other forum members the O/D is the weak link so if your gonna give it stick put it in PERF mode.

Just my advice but that's what I do all the time, drive in Perf and kick it over when I'm off throttle on a straight and 80km or above. 12 months and no dramas (touch wood).