Guys I've got a new TO4E but the oil inlet is different than the last one I had, it's just a threaded hole. It looks like a 1/4"NPT but I am not sure.. any confirmation here? There's a cool hot rod store near my work so I can pick up the fitting after work today.

it is a 1/4" npt

Something else I noticed, the turbo I had on before used a flange mounted onto the oil inlet, to which the delivery hose attached. On the turbo side of the flange the hole the oil actually went through was tiny, this has something to do with forcing the oil in to the turbo bearings? Just curious because if I just go buy an 1/4NPT to -4 adapter will it do the job, or is the part # listed on turbonetics different than this and has a smaller delivery hole?

you need the small delivery hole, AKA "oil restrictor" The rx7 puts out really high oil pressure, especially at start up. It's too much for the turbo to handle, which is why they put the restrictor there.

That's exactly what I thought, is something like this available that is part of the actual fitting or is it accomplished using a restrictor pill? And where could I get either? Thanks for all the help.

Get a regular 1/4npt to -4 fitting. Drill/tap the npt side for a socket head pipe plug (probably 1/16" or 1/8" npt) get a few socket head pipe plugs and drill a few different size holes in the pipe plugs. I'd drill .040, .060, .080 and a .10 hole in each one. Start with the small restrictor and keep changing them out with a bigger one untill the turbine seal starts to let oil past. Once you found the restrictor that is too big then kick it down a notch. Bing! you have a restrictor that is set up for your turbo! https://www.nopistons.com/forums/pub...IR#>/smile.png

Thanks for the info, pretty funny I went over to the other forum and just got done reading your post on this from a while back. Your solution makes sense with parts I can easily get today, perfect!

The restrictor in my oil line is 0.129 inch or 3.28 mm. No smoke even with the higher pressure regulator.

MJW- yeah, seems I post to this question a lot. I like this way because it's tuneable.



MikeL- wow that's a pretty big restrictor! I bet you have an awsome return line. I think the one I ended up with in my TD07 was a .081". I have a 5/8" return, what do you have?

The oil feed line actually came with the GReddy TD06 kit for my 2nd gen. I've used that line for both the T-66 that I had and now for the T04E. The return line is 5/8".

The size of the restrictor depends alot on oil pressure. My car hits 150psi of pressure max, if I run anything bigger than 1.6mm I get smoke. I run a -12 return also. If you have a car that only hits 80psi you can run a bigger restrictor. I have never used or seen anyone use a restrictor on a Mitsubishi turbo when they used the feed line that came with it. Every Garrett turbo I have ever used required some sort of restrictor to keep it from blowing oil, even when a Mitsubishi feed line was used. I know HKS sells an oil inlet adapter that bolts on that has a 1.5mm restrictor built in.

I never heard of this. All i use is a -4 AN line and i haven't had any problem with smoke.

IGY , what did you do to get your oil pressure up to 150 ?. , I am presently running 9000rpm,s and would like to go up a bit more to about 10,500 https://www.nopistons.com/forums/pub...#>/biggrin.png .

Well to tell you the truth, I did nothing. I have tried changing the oil pump and checked the front cover oil pressure bypass. The last thing to change is the regulator. I have been waiting until the next time I pull the motor to systematically change things. 150psi is just a little to high for my liking. The damn motor is coated in oil because it blows past all the seals everytime I rail the car. I originally thought it was a sticking requlator, but I played with it and it seemed to be OK. After changing everything else I am leaning toward a bad regulator again.



Doesn't your oil pressure go to 110-115psi? Every stock regulated FD motor I have seen an oil pressure gauge on has gone to 110-115psi. As a general rule you need 10psi of oil pressure per 1000rpm's.

Yeah i see about 110 psi , keeps ****** up my oil pressure gauge sender (100 psi) .

Ha ha, cool. You have a secondary bridge and have only reved to 9000rpm's? Dude, it's way more fun if you go to atleast 10,000. With 110psi you are good to 11,000 rpm's technically, let that bitch rip! Don't forget to have someone take a picture of your face after you get out of the car, the look is pricless.

We both have -10 (5/8"), -12 is 3/4"

So they never put restrictors in the mitsu "kits"?? Maybe I should try to run a larger orifice than the .081" (2.06mm) I have in there now then. After ~3000 miles of driving the turbo still feels the same as far as shaft movement though.. hmm I just have stock 13B-RE oil pressure so maybe I could get away with a bit of a larger orifice?

I plan to go up to about 10,500 eventually , but I have to hold up at 9000 until I fix my fuel problem , my ****** clutch is SLIPPIN AGAIN !!! , have to hustle up on the OS swap . I had my turbo re done with all new seals bearings (free of charge of course) and I am still getting oil smoke at the higher revs , my oil feed hole is 3/16 , the supplier "down under " says that the turbo will leak oil at any inlet pressure above 105 psi !!! , they suggested trying a "lighter" oil , I use 50 body they said to go down to 40 , what ya think ??.

Ok, I have no experience with your turbo, but I run a restrictor a third the size of what you have on my big shaft T series housing. If it was me, I would be looking for a second opinion before I changed the weight of oil I was using. Oh wait that's what you are doing here. You should be seeing between 45-60 psi of oil pressure at idle on the bridge. If smoke is comming out the turbo then you are getting too much flow and the center cartridge cannot drain fast enough. If you go down on the restrictor size, less oil will enter the housing. There should be no/very little pressure in the housing.



This is an example, in no way are the numbers accurate they were picked out of thin air to make a point. With a car that makes 80 psi of oil pressure you will get 10 oz per second through a 3/16 size hole. At 110 psi you will get 14oz per second through the 3/16 hole. If you make the hole 1/8 and run 110 psi you will be back down to running 10 oz per second again. So high pressure smaller hole will = the lower pressure bigger hole volume.



If it was mine I would make the restrictor 1/8" and try it.

Actually I was wrong about the oil feed size , its actuallu 3/32".

I still had problems with the the same size hole. That is around 2.3mm, my restrictor is 1.5mm. I know many people with 1.5mm restrictor's on rotaries. If I were you I would still try a smaller restrictor. I actually have more problems when my oil is old and thin and the pressure drops, than when it is new and higher pressure.

IGY: What would you recommend for a restrictor on a T04E with a 1.32 Housing and .70 wheel?Its on a stock port 13BT.



Thanks

I actually had a smaller hole ib it (it is a WEBBER carb jet ) and I had it enlarged 'cause my turbo builder said he did not like how the inside looked so on his reccomendation I opened it up. When the turbo was new I had that same jet , same oil (weight & pressure) and there wasnt any smoke at all , I think the problem lies with the CHRA itself.

.08" or 2mm is a nice starting place on the TO4E. If it smokes then go down a size. Earlier in the post setzep gave some good info.

It is entirly possible that the CHRA is bad. What was the size of the original jet that you used? What about trying something in between?

I am done fighting with it , I am sending it back to AUSTRALIA to have it repaired / replaced its still under warranty , I dont want to go too small with the restrictor 'cause it may stop the smoke but may end up shortening the turbos life . I think the opening I have now is good (and the supplier did recomend this size too ) , I am also going to put an oil cooler in the supply line to get even cooler oil to the turbo which is supposed to be good for it.

oil cooler isn't a bad idea if you have the space