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Discussion Starter · #1 ·
I'm posting here since you have lots of Japanese Supras in Australia:

I'm thinking of buying one of my friend's TT here in Japan (I'm NA for the moment), his boost gauge reads 0.7 kg.cm2 at full boost. The car was already tuned when he bought it, so we were wondering if this was the factory value or not. As far as I know, it's the standard pressure on US versions, but how about the Japanese ones? Does anyone know this?

Thanks for your help.
 

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J-Spec 4 Life
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my car was running about 11-11.5 psi stock
 

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Discussion Starter · #4 ·
Then, I've found around 10psi...Either you were boosting high, either he's boosting low :scratch:

 

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J-Spec 4 Life
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That was is a catback exhaust (still had the stock downpipe on)
Plus I think you get different readings depending on where you read your boost from. Mine was from teh intake manifold. I think if you take it from the turbo your reading would be about 1psi higher. Can't remember honestly and I also could just be completely wrong.

But from what I know 10 or 11 psi is stock boost. If I set my boost gauge to anything under 11psi it goes crazy and doesn't regulate boost at all. I'm assuming the 11 is the ecu controlled stock boost. And the instuctions on the BC said that you can't set your boost under what the ECU has set.

Now I have it set to 11.5psi 0-62mph 14.5psi 62mph+
 

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Discussion Starter · #6 ·
ok, I got it. I don't know where they take the pressure from on his car...but anyway, it sounds pretty normal. The boost pressure is untouched, that's what we were trying to find out as the car as a tuned ECU under the passenger seat, a blow off and at least a catback (couldn't see anything else that night, the car was too low anyway)...but no boost controller.
 

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That sounds like it's only making stock boost (from memory) that is 13 psi which is really safe for a 2JZ motor.

To increase boost you will need to fit a boost cut defender which alters the signal going to the ECU or fit an aftermarket ECU with that feature biult in.

I regularly boost to 21 psi with no problems....so far!
 

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TT Aero said:
I regularly boost to 21 psi with no problems....so far!
VERY interesting!!!
I know at 14.5 my car feels strong. I've spiked to 22.8 and car just started to spin tires in 3rd. When you say regularly is that daily or only in race scenarios :sadance:
I owuldn't mind occasionally pushing 16psi. I have Fuel cut but so far haven't had the time/interest to install it :rolleyes:
 

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My car is not currently my daily driver but still gets used fairly regularly.

I have my ebc set to stock boost mostly for street but crank it up for track days or when I feel the need.

I have a high flow stock mount intercooler down pipe and high flow cats with three inch exhaust.

My best pass to date is 12.95.

If you,re breaking traction in a straight line without trying to induce it, check that your rear tyres haven't gone hard. I found that I could launch hard without much wheel spin but would brake traction when no 2 turbo cut in, it's a great feeling (bit dangerous in the wet) but that stopped when I replaced my tyres.
 

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Discussion Starter · #10 ·
Thanks for the feedback...Finally, I've bought another car than my friend's.
I've found an untouched 100% original 94 RZ 6-speed owned by an old man. Judging from the tires, brake discs and the overall condition of the car, it feels like it has never been abused at all and well taken care of.
The odo reads 98000 km, so I was just wondering what kind of average mileage do those ceramic turbos could handle at the normal pressure. The car doesn't smoke on start-up and builds up boost very naturally. I have to admit that this is the point I'm worrying about since I'll use it every day.

thx
 

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Doin' the Monster Mash
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Don't sweat it, most of us are just more regular on the australian site rather than this one :)

The standard ceramic turbos are good for well over 100,000kms, depending on how well the cars been treated.
 

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Discussion Starter · #13 ·
No problem, Macross, everything is allright :)
It's just a lot easier for me to discuss in the australian forum, as you guys have a lot of japanese Supras and as my japanese is not always good enough to talk with shop employees and such. I know the Supra as I had a NA, but I don't know all the little tricks and tips on the TT yet.
 

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heavyfoot said:
The odo reads 98000 km
My odo is about 86K everything still feels good. Seq setup works fine and everything. Like a poster above said just maintain the car and they'll last long enough
 

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Discussion Starter · #15 ·
The car feels really smooth, I guess it would be ok.
It's back in the shop for the timing belt change and for the active spoiler acting weird, but apart from that, it drives fine. As I drive it all the time, the first thing I will do is to put a turbo timer to let them cool down properly.
 

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Discussion Starter · #17 ·
It doesn't go down if I ask him to when the car is stopped and even sometimes when it drives on the Auto position. The car is still under Toyota warranty anyway, they've changed the active spoiler computer assy and they said it's working fine now. They've said they've put the old computer in the trunk. If it's there, I'll let you know just in case someone is interested, but it wouldn't work well I think.
Anyway, I have driven the car several times, but the final delivery is on monday. I'll see then. It took a hell of a time to get it registered and ready to drive.
 

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heavyfoot said:
It doesn't go down if I ask him to when the car is stopped and even sometimes when it drives on the Auto position.

It won't go down when the car is stopped and the engine is running. You have to stop the engine then turn on ignition then press the button.
 

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Discussion Starter · #19 ·
Thanks davo, there was actually a problem that the shop fixed up. They decided to change the computer assy, it's fine for me as it was under the warranty of the car and it works fine now.
 
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