Hi guys im new to owning a VR4 and have some question.

[TREX]

Hey guys, I have just purchased a vr4 legnum. Mods: coilovers, wheels, De-Cat and Catback exhaust.
I want to up the boost a little what do i need to do so i can saftly run 12 PSI? Fuel pressure reg / FMIC kit ect.
Also can i use a t piece that runs between the actuators and to the turbo front housing or do i need to run an electronic boost controller?

One more thing, Do i have to run iridium plugs?

Thanks heaps

[Kenneth]

In Australia, I would be wanting to put in a decent aftermarket intercooler. You should be able to do 14psi no problems, though if you have a manual with standard clutch, that could be a weak point.

You really need to tune the ECU to get the most benefit from upping the boost. As such, you shouldn't need any external boost controller.

You should be going to a colder plug. BKR7EIX or equivalent. Iridium isn't necessary, though you want a high quality plug as the boost can destroy a crappy plug very quickly and causing issues running at decent boost. Some things are not worth being cheap about, spark plugs are one of them. Personally I have always run BKR7EIX and have run boost into the 20s before getting issues. I also haven't suffered any premature plug degradation with these.

[TREX]

Hey Kenneth,

Thanks for the quick reply.
My Legnum is auto so clutch isnt an issue and the gearbox should be strong enough for what im wanting to do.
When i do the intercooler do i NEED to do hard piping throughout the engine bay?
When you say Tune the ecu, do you mean replce it with an aftermarket ecu or is there someone that chips the standard ecu (like Niztune for nissans ect)
Alos are the BKR7EIX plugs gapped to 0.8 or 1.1?

Thanks heaps for the help :)

[elnevio]

/Welcome

BKR7EIX plugs are gapped to 0.8mm from the NGK factory. Although I always check mine with feeler gauges, just to be sure. Steer clear of BKR7EIX-11 plugs, because although they will fit, they are pregapped to 1.1mm, which is suitable for the NA 6A13 engines, but not the VR-4's 6A13TT, which requires the smaller gap.

You do not need to replace all the engine bay intake piping with hard pipes if you install a larger intercooler. Hard pipes can provide a better response, as there is minimal flex/ballooning in the intake system then, but some say that it can make the experience a little less smooth. I am certainly aware of many VR-4s with aftermarket intercoolers that have retained the original soft pipework.

The stock ECUs can be reflashed with the relevant software and cables. It depends which ECU you have as to how easy it is. The early cars used a 7201 ECU which is fairly limited. The later cars used the 7202 and 7203 ECUs which are much more flexible and easier to tune. There was a brief period between the 7201 and 7202 when they used a H8 ECU, but that's not really the easiest to mess with. I'm guessing you have a late-ish facelift VR-4, being in Australia, in which case, you probably have the 7202 or 7203. If you fancy taking it out, you can open it up and see which one you have - it's stamped on the chip in the ECU. The ECU is located between the two front footwells and has the four green plugs going into it.

[TREX]

Yer I have a 1998 post facelift legnum. Can any tuner flash the later model ecu?

[Kenneth]

As Nev said, standard soft pipes are fine. I have been running mine up into the 20s no problem :D One trick is to use a couple of beefy cable ties around the middles of the soft pipes which prevents them balooning so much.

You should probably good to ozvr4.com and join. There is a resident tuner goes by the handle TMESteve or some such. He is fairly well recognised as an experienced tuner of VR-4s and has good feedback from their members.

[TREX]

Thanks guys.

Sorry to be a pain but i have just been told to get an upgraded fuel rail loop kit. What is this? is it worth having? and where can i purchase one?

Thanks again

[Nick Mann]

IMO that is not necessary until you have gone bigger turbos and injectors.

[Grid]

Thanks guys.

Sorry to be a pain but i have just been told to get an upgraded fuel rail loop kit. What is this? is it worth having? and where can i purchase one?

Thanks again

It's a piece of fuel piping which feeds the rear bank of injectors from the front one. The stock one is said to be restrictive when you go for big power gains and need to flow much more fuel than stock.

[97legnum]

http://www.3sx.com/store/comersus_viewItemBundle.asp?idProduct=1164 That's the fuel loop they are talking about. I just made my own with two fuel rail adapters, two AN6 strait fittings and a loop of 8mm id braded hose. What I couldn't recommend enough is a high flow fuel pump!

[TREX]

Hey Guys,

Thanks for the great replies I have 1 last question.
Can you pull a map from a facelift legnum ecu or do you have to do coding to tune them?
The reason i ask is because i have one found 1 tuner that is 100% sure he can tune these (Steve Hunt TME motorsport) he is located in Sydney and wont be in Brisbane for another 3 months.
I have a tunere here that a fair few mates use for evos and a 380 swapped mirage on gas all with standard ecus. He has said he can tune it if you can pull the map from it but not if you have to do coding.

Thanks heaps guys :)

[Nick Mann]

Get Steve from TME to do it. If you search for threads on the subject you should find enough info for anyone to have a go, but Steve knows what he is doing.

[TREX]

Hey guys,

Just jumped in my car and drove up to the shop, when i tried to start it to come home it didnt star (it didnt crank or anything) It made a loud buzzing noise (like an after market fuel pump).
I tried about 3 or 4 times and it just did the same and then it eventually fired up and drove fine.

[Nick Mann]

It could well be the ignition switch. They seem to be failing with increasing frequency at the moment.

[hbkuk1]

I agree with Nick mine did this and it was the switch

[TREX]

Hey guys,

Ive just installed a 600x300x76 intercoooler on my legnum and it seem to have more lag and feels like it has lost power significantly.
Any ideas as to why this could have happened.
Also i am about to instal an avc-r and was wondering if anyone has a wiring diagram for a facelift legnum? also what boost can i run without have the car tuned? (the car will be tuned in 2 months)

Thanks in advance, you guys have been an amazing help.

[Davezj]

possible boost leak

what does the boost gauge say is it still boosting to the same level.