I'm getting the last things to finish up my turbo em1 and was curious if anybody would know if I need a oil resrictor for my turbo, it's a stock evo turbo and I've searched all forums and I came up empty.... anybody??

 

afaik the evos don't use a restrictor as OEM. my EVO 8 turbo didn't have one

 

Yeah I didn't think they did, but since they use the head to provide oil and I'll be using the oil sending unit location which might have more pressure.

 

After a little searching seems the 4g63 and a b16 have very similar oil pressure specs and considering the feed line from the stock turbo is huge I don't think I would need one if I run a -3an line.

 

You should be fine. the td05hr chra has a fairly robust bearing and seal system.

 

There is a restrictor is built into the chra

 

Not on mine

 

what turbo are you using?

 

MHI TD05HR-16G6

stock EVO 8 turbo modified to confirm to the FIA rules for rally cars.

 

To set the record straight I pulled my oil feed line and confirmed that there is indeed an oil restrictor built into the chra of a oem non rally spec td05hr 16g. It is below the threads of the banjo fitting .

I will now be drilling out the restrictor built into my aftermarket feed banjo fitting by Kinguwa

 

Been running an evo 8 16g for 2 years with -3 line off the oil filter. Sees 100+ psi on cold start and no issues so far, even at 15+ psi boost.

 

technically that's not a restrictor. my CHRA has one too. It's simply the oil port that feeds the CHRA. if you were to cut the housing in half down the middle of the shaft centerline you would find out that the hole is the same size as the oil passages, therefore technically not a restrictor.

in any CHRA regardless of brand the oil passages that supply the journal bearings are only up to 3mm in diameter, most around 2-2.5mm

the way MHI designed the turbo with the large compressor side seal plate, oil slinger plate, and overall bearing size, it doesn't need one. regardless of line size and pressure the passages can flow a finite amount of oil. if you think you're starting to have seal issues then a restrictor can help slightly extend life but once the seals start to go it's basically rebuild time, similar to a Holset, you don't know it's too late till it's too late lol.

 

I couldn't find a td05hr cutaway but here's one of a td04 from a 3000gt/stealth.



you can see that the feed design is a bit different with all of the ports coming off the feed directly. in the td05hr CHRA there's one hole from the feed line port that divides internally.

one large feed port to the thrust bearing, thrust bearing collar, and compressor seal backplate area. then there are two smaller fees ports that go directly to the journal bearings.

the reason for the large area behind the feed line fitting is they are using it like an accumulator... it allows just enough oil volume to build up where and small changes in flow and pressure won't result in a starvation situation within the turbo.

So imagine that instead of all of these holes in the feed port the EVO turbo has one feed port that branches off to supply all of those areas, with the thrust bearing port being the largest.

 

That makes perfect sense. I stand corrected still gonna drill this banjo bolt out

 

I know way too much about turbos lol

 

You're definitely in "Jedi" territory now.. Now you just need to get on "the counsel".

 

Me likes the dark side better