Jump to content
SAU Community

Recommended Posts

Hey guys.

I'm in need of some advice, I have had a conversion from an rb25de to rb25det done with autosport (kirrawee) in my 34 and now I'm facing some transmission problems.

Okay so these are my options.

1) Run the factory turbo ecu and have my transmission thump in 2nd gear & lose my tip-tronic mode..

Or

2) Run the factory N/A ecu which runs the transmission fine but the engine very rich (lots of black smoke out of the exhaust) & have a fuel pressure regulator tap fitted to run 20% less fuel..

Any input would be very much appreciated here,

Cheers.

I hate to be the bearer of bad news here (and believe me, its bad)

My car has been off the road for 2yrs+ due to this and a host of other issues relating to it.

The way I see it, the easy way out is the N/A ECU with a piggyback ECU on the N/A ecu to get the tune right. (You cannot run NISTune on a N/A R34 ECU)

May want to steer away from the E-Manage Ultimate if you are choosing this ECU. Mine ended up with a pinging issue which destroyed the engine on the dyno, before I ever got it back.. A Haltech Piggyback ECU did not have this problem.

Whether its acutally the ECU or wiring or what have you, I do not know. Just a word of caution...

Other Options:

Fully Manualized Auto Shift kit to get rid of the Transmission ECU

Manual Conversion

Could then use a standard Turbo ECU, or NISTune or one of the other many many options available.

I read here that its possible to get the Transmission ECU to behave seperately and use a Manual standalone ECU for the engine, but after thousands of hours it was deemed to not work. Called many people who didn't want to touch it, and was prepared to fly the only person on SAU to have ever apparently done it down from Brisbane to have a look at it, but that never seemed to eventuate.

If you ever, ever, ever planned to do a manual conversion, or totally beef up the transmission, now is the time.

Alternatively, should the guys in WA get this sorted through some sorcery, I am willing to ship my car to them (from VIC) to do it too, lol.

I hate to be the bearer of bad news here (and believe me, its bad)

My car has been off the road for 2yrs+ due to this and a host of other issues relating to it.

The way I see it, the easy way out is the N/A ECU with a piggyback ECU on the N/A ecu to get the tune right. (You cannot run NISTune on a N/A R34 ECU)

May want to steer away from the E-Manage Ultimate if you are choosing this ECU. Mine ended up with a pinging issue which destroyed the engine on the dyno, before I ever got it back.. A Haltech Piggyback ECU did not have this problem.

Whether its acutally the ECU or wiring or what have you, I do not know. Just a word of caution...

Other Options:

Fully Manualized Auto Shift kit to get rid of the Transmission ECU

Manual Conversion

Could then use a standard Turbo ECU, or NISTune or one of the other many many options available.

I read here that its possible to get the Transmission ECU to behave seperately and use a Manual standalone ECU for the engine, but after thousands of hours it was deemed to not work. Called many people who didn't want to touch it, and was prepared to fly the only person on SAU to have ever apparently done it down from Brisbane to have a look at it, but that never seemed to eventuate.

If you ever, ever, ever planned to do a manual conversion, or totally beef up the transmission, now is the time.

Alternatively, should the guys in WA get this sorted through some sorcery, I am willing to ship my car to them (from VIC) to do it too, lol.

Thanks for your response,

Okay, I made a call to JEM about this and they said they can use a Haltech ps2000 which they wire in with the NA ecu so that my transmission works and have the correct tune for the engine. Does that sound about right to you? also they quoted me $3200 to supply & fit that system, do you think this would be the best way to go in order to avoid any issues?

I haven't heard of a Fully Manualized Auto Shift kit, please explain further??

(be aware I am just a lay man who has heard many things about this one specific issue only)

Apparently the transmission itself is much the same, as in the auto box. It's all in the wiring and looms etc. In theory if that is the case it would be possible to have a GTT Auto ECU run the box, as long as the ECU is seeing what it is expecting to see. Except this seems to be massively difficult in practice. I suppose you could throw a R34 Turbo Auto Trans in there too but I was advised (by auto shops) that it is the same.

A fully manualized kit is basically what it is, you manually shift up and down gears with a ratchet shifter. Think of it as permament triptronic mode. I was advised this would negate the need for an ECU, as, well, nothing is controlled electronically anymore when it comes to gears. I.E you could just put a manual ECU in there, and shift all you want via the shifter, manually. Again, heresay, couldn't find anyone who has ever attempted it.

Manual Conversion will fix it. I personally didn't do it as I had already spent tons on the transmission upgrades and was 'told' it'd be easy to get working (seems not). This may be fixable in my case if it really IS just wiring, but, noone seems to want to try/test this as it's been such a nightmare for everyone involved.

From my shopping around, a PS2000 I was told was overkill. (Lots of features that may not be needed) In my car a Platinum Sprint 500 was enough to get the tune right, which unfortunately resulted in me discovering a plume of oily smoke appearing at 6800 RPM due to damage caused by epic pinging of the previous ECU.

I dont know the rules regarding ECU's in NSW. In VIC they're always illegal, so a Haltech is nice as it's physically very small. (No need to hide it under passenger seat).

However if I get an EPA I'm doomed, so I've already started thinking about how to get around the problem when it inevitably occurs.

According to haltech.com.au, the ECU itself (the PS2000) is $2400. So them quoting the price they did to supply, fit, install, and tune is quite reasonable.

That said, the Sprint500 is $940.

THAT said, go with whatever the tuner is more comfortable in tuning. ESPECIALLY if you are in the situation you are in.

But as suggested before, if you are considering doing a manual conversion, it will fix your problem too. Ditto for upgrading the transmission (99%, according to MV Autos). I wouldn't use a piggyback ECU unless I absolutely have to (mainly due to VIC laws), which appears .. heh, I do.

greg did you ever consider buying a complete wiring loom/ecu etc from a wrecked auto GTT.. would only cost chips to buy but quite a few hundred to fit..

surely i hope its not something simple like changing a few pinouts on the ECU.. (im sure u have checked this but want to be sure)

greg did you ever consider buying a complete wiring loom/ecu etc from a wrecked auto GTT.. would only cost chips to buy but quite a few hundred to fit..

surely i hope its not something simple like changing a few pinouts on the ECU.. (im sure u have checked this but want to be sure)

I bought both wiring loom and ecu for a auto GTT and supposedly I'm being told from the w/shop that the entire body wiring harness (from front/inside/rear of the car) is different?? Which just doesn't make sense to me..

greg did you ever consider buying a complete wiring loom/ecu etc from a wrecked auto GTT.. would only cost chips to buy but quite a few hundred to fit..

surely i hope its not something simple like changing a few pinouts on the ECU.. (im sure u have checked this but want to be sure)

Yeah, this I believe was done, but similar to to the OP, I was told all the plugs don't fit fully, I.E, the loom from the Turbo GTT (auto) can't be made to fit the N/A Auto on the car side regarding the dash and auto loom, and getting complete wiring from a GTT still didn't help as there was no way to actually connect it to the car as it was (inexplicably) different?

My car is a Series II, it was (and still is) a hugely frustrating case of "It really should be the same, but its inexplicably different and messed up". Thats not to say it wasnt attempted, I believe both looms got butchered and hacked together so very badly that in the end when the solution was "Get a N/A loom and a piggyback until manual conversion/fully manual auto".. a completely new loom had to be purchased for the N/A car, as neither were in any shape to be used.

(and then the loom was from a S1, and would you know it, the ABS unit from a S1 R34 has different plugs to a S2 R34?, but luckily the S3 R34 and the S15 have the same ABS unit).

I don't think anyone involved knew what a nightmare it would be until it was actually attempted.

I'm sure its possible to do in a backyard if you are an elite auto electrician (as anything is possible), but in the real world the solutions are:

"f**k it do a manual conversion"

"f**k it, use a piggyback ECU"

"f**k it, don't put a turbo engine into a N/A R34"

"f**k it, put this built engine into a completely different car"

Oh and pro tip out there for anyone reading this, don't try and use a BC 2.9 Stroker kit into a R34 NEO engine, because you're gonna need custom pistons that noone has ever made before, apparently.

Seriously, "abandon all hope, ye who enter here" kind of shit.

/rant

Thanks for your response,

Okay, I made a call to JEM about this and they said they can use a Haltech ps2000 which they wire in with the NA ecu so that my transmission works and have the correct tune for the engine. Does that sound about right to you? also they quoted me $3200 to supply & fit that system, do you think this would be the best way to go in order to avoid any issues?

I haven't heard of a Fully Manualized Auto Shift kit, please explain further??

If your going to spend $3200 to fix it, do a manual conversion.

Basically the N/A ECU also houses the transmission computer (that's why the transmission works)

The Turbo ECU doesn't contain the transmission computer, so the transmission shits itself and goes into limp mode (2nd gear)

If the guys are awesome they can piggy back the turbo ECU in parallel with the N/A ECU and it'll work just fine. Basically have two ECU's but cut the wires that drive the injectors and ignition packs coming from from the N/A ECU plug. This allows both ECU's to see all of the correct signals, but allows the turbo ECU to do the work controlling the engine, and the N/A ECU left controlling the gearbox.

Realistically there are only the key wires that need to stay connected to the N/A ECU.....Pins # 4,5 20, 24, 25, 29, 31-41, 44-46, 48, 54, 55, 58, 60, 67, 70, 72, 79, 80, 113, 115, 120-122

Maybe a couple more, but that should be it

Edited by 666DAN

Basically the N/A ECU also houses the transmission computer (that's why the transmission works)

The Turbo ECU doesn't contain the transmission computer, so the transmission shits itself and goes into limp mode (2nd gear)

If the guys are awesome they can piggy back the turbo ECU in parallel with the N/A ECU and it'll work just fine. Basically have two ECU's but cut the wires that drive the injectors and ignition packs coming from from the N/A ECU plug. This allows both ECU's to see all of the correct signals, but allows the turbo ECU to do the work controlling the engine, and the N/A ECU left controlling the gearbox.

Realistically there are only the key wires that need to stay connected to the N/A ECU.....Pins # 4,5 20, 24, 25, 29, 31-41, 44-46, 48, 54, 55, 58, 60, 67, 70, 72, 79, 80, 113, 115, 120-122

Maybe a couple more, but that should be it

Thanks for that, gives me some good insight and hope that this issue may be fixable for less than $3000 upwards...

See that makes more sense to me than replacing the entire body wiring harness! I reckon it would change nothing personally.

As soon as I get my car back I need to find a gun auto elec to help sort out this issue.

Thanks for that, gives me some good insight and hope that this issue may be fixable for less than $3000 upwards...

See that makes more sense to me than replacing the entire body wiring harness! I reckon it would change nothing personally.

As soon as I get my car back I need to find a gun auto elec to help sort out this issue.

I was under the impression there is a seperate Transmission ECU, not that the N/A ECU has Transmission elements in it?

(dan is the aforementioned guru thats the only one who has ever done this before) :P

Lol forget my rant it's back to front....the n/a has a seperate TCM so you need to disable all of the wires on the GTt ECU that are also trying to control the gearbox. It would be getting mixed messages. A manual Gtt ECU should do the trick...and let the auto work on it's own

Manual GTT ECU did not work when it was tried on my car...

Need some kind of super duper guide with pictures methinks.. if I ever get my car going I'm still offering to drive it up to brisbane for your input on it and pay a shedload for it. To the OP - This is the scenario you are in and it's not a good one, not a good one at all!

Ok they must have made some changes somewhere as I could run my old car off the manual GTt ECU and retain shifting...the factory tune just didn't suit it....back when it couldn't be nistuned :(

Okay, I've spoken to a Nistune tuner workshop called Croydon racing developments don't know if you've heard of them or not? they tell me they can put a nistune motherboard in my original N/A ecu which should rectify the issue I'm having as the transmission will work coincided with the correct tune for my engine :)

they quoted me $1500 to do this. I'm going to make sure I get that in writing to cover myself. To me this sounds like my cheapest and best solution to fix this problem.

What do you think Dan?

Edited by Myfine Skyline R34!

If CRD can do it that's a good option, maybe things have changed but I didn't think they could rejig the n/a board?

Yeah I thought that could be the case but they investigated with nistune and told me they were confident they could make it work with my na ecu.

like I said I'm definitely getting a written quote for $1500 just incase of any issues I'll be covered, I don't want that $1500 bill turning into $4000...

I did look into it and Trent @ Status said it couldn't be done, in addition to Dr Drift also stating it couldn't be done after taking a look at the N/A ECU, apparently the setup of it is different and missing a lot of components that Nistune requires to work.

But if CRD can do it (or anyone), please post here as it massively solves my problem too :P

hmmm I also thought Nistune doesn't work for the N/A >_< But CRD are a reputable shop so i guess they'll try hard to do it right! Try Powertune as well, they've done outstanding work on my mates R34 (gtr) but they know their way around and if they don't know something they'll try to get you the best solution :D

good luck!

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


×
×
  • Create New...