1uzfe oil pressure PSI

The 1UZFE EGR Delete Kit is available for sale here.
Hey Steve, it's been a while since I've seen you or your ride. What's your ride like since I last saw it? I remember it having a single turbo, stock auto tranny, and you were putting out about 300whp at the time..

Anything change? How has the turbo been so far? Lot's of trouble, any regrets?

I remember you did the boost cheaply too.. Made the extractors from scratch, etc. Nice work.. Even did the needles on you cluster. Ha HA..
 
I haven't heard from you for a while. Thought you've gone MIA. LOL. The whole setup is much better now. Nothing is stock anymore. It's dynoed at 380 with a calculation of 28% loss to the wheels. Looking to dyno again after changing the turbo seals and to tune the tranny a little bit more conservative. It now has bigger turbo (the biggest one that can fit in my setup now), completely built tranny, complete fuel system, standalone AEM EMS...etc. The cost eventually exceeded my initial calculation.
 
^^ Yeah, I went MIA for a while, but was always around.. Lost interest once my SC4 started to fall apart. Got it back in shape again.. It's running great..


Ok Steve, I see you stepped up. You da man!!!

You built up the auto tranny too, Boost logic is my guess? That's a good idea.. I almost did that myself until I saw the price with shipping.. I went cheap and just decided to blow out the old stock trannies instead.. They are cheap to replace and swap out I figured..:p

A bigger single turbo, ok.. Wicked!!! How about the internals of your 1uz-fe?.. Did you replace the pistons, studs, etc..?

I don't think I'll be racing you now Steve..Must be fast as hell.. Did you beat James yet with his 2jz powered SC4?

Lastly do you still have your 350KX kicker amp in the back thumping?
 
Steve, i just got my Defi gauges working and i saw 110 psi at cold start up on my newly built motor. With my sandwhich oil distribution plate, i am coming off a low pressure port and registering 25 psi to each turbo.
Ryan
 

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John,
I'm glad you got the SC up and running again. I guess you don't run NOS anymore due to its destructive power. :p I think you can try the centrifugal supercharger that can be set up under $2K. The most successful runner is KC95. He ran almost a flat 12 sec for 1/4 mile.

For the tranny, I didn't go with Boost Logic. Too expensive. I went with Red Eagle HP rebuilt kit and IPT valvebody shift kit. Half price of Boost Logic.

I still have stock pistons & rods on an low mileage 91 1UZFE, but I'm using Cometic headgaskets lowering compression down to 9:5:1 with ARP head studs.

Ryan,
I didn't pay attention much to the oil pressure to the turbo. I asked Turbonetics builder if I need an oil restrictor, but he said no. That's why it gave me a headache now. I think he's not aware the 1UZFE has more oil pressure than other cars. From what I researched, there shouldn't be no more than 35 psi going to the turbo. If you have 25 psi, then you're in very good shape.
 
What's your psi at idle on cold start and after warm up?

Ryan
I didn't install the oil pressure gauge, so I don't know. From the researches, many turbo guys say the turbo leaks the oil the most when the engine idles or when it's cold. So that can relate to the created high pressure when the engine idles or is cold. There's no perfect solution for lowering the oil pressure to the turbo. It can make the turbo hotter with less oil traveling through it. A turbo timer is neccessary in this case.

Red Supra,
Very interesting that you measured the oil pressure at different engine conditions.
 
I didn't install the oil pressure gauge, so I don't know. From the researches, many turbo guys say the turbo leaks the oil the most when the engine idles or when it's cold. So that can relate to the created high pressure when the engine idles or is cold. There's no perfect solution for lowering the oil pressure to the turbo. It can make the turbo hotter with less oil traveling through it. A turbo timer is necessary in this case.

Red Supra,
Very interesting that you measured the oil pressure at different engine conditions.
If there's oil seal issues with high pressure oil supply..
Most put a restrictor on the oil inlet side..
When I fitted twin Nissan turbo's I had to fit 1mm oil restrictor on each oil feed line..
 
I'm afraid 1mm is too small, so I use 2mm hole. Do you think that's good? I never had to use oil restrictor on 4 banger Hondas. :rolleyes:
Depends on oil pressure ?? Also SOME turbo's have built in restrictors..
1mm is easy enough for a ball bearing turbo and 80Lb oil pressure..
I wouldn't use a restictor on a shaft bearing turbo..
If it smokes with shaft bearing ?? Chances are there's issues with oil return hose to sump..
Or there's blow by build up in crankcase...
 
I took the turbo back to the rebuilder and he said the bearing is worn out and it seems like oil starvation. WTF? I told him I didn't have any oil restrictor before, so that's impossible. Maybe he just made up something to cover up his mistake.

The return line has good angle, and the crankcase is vented out. So I can rule those out.

I just bought an oil pressure tester today and even with the 2mm restrictor, the oil pressure is surprisingly at 75 psi at idle.

Is there a reason you wouldn't use an oil restrictor on journal bearing turbo? Not enough oil?
 
Oil coking can cause bearing failure.. When engine is turned off while turbine CRA is hot...
Also the tune can make turbines very hot with conservative engine tune.. Too rich and retarded... Fuel burns in exhaust not engine..
Shaft turbo's are generally not water cooled and rely on oil to cool CRA if oil flow is too restricted would cause issues.. Flow is more important than pressure..
Unfortunately fitting a restrictor doesn't necessary limit pressure .. It limits flow ...
Pressure is a restriction of flow..So in shaft type turbo a restrictor is not required...
 
Everything that you listed is valid, but I could rule them out in my setup. I've researched a lot, and the last thing that can blow the turbo seal is too much oil pressure even with journal bearing turbo as in the opposite of oil starvation (not in my case). I'll try the 1.5mm oil restrictor and see how it'll go.

And thanks for all of your gentlemen's feedbacks.
 
I have to ask...
When you checked oil pressure ?? Was the oil feed connected to turbo with pressure gauge Tee'd off ?? Inline with oil supply ??
Imo it's an old excuse to say oil supply killed the bearings...
It's a bit like being a little bit pregnant though..
 


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