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What size turbo oil restriction hole for 918 blade engine
mark chandler - 8/1/17 at 04:36 PM

Finally got my new Turbo on after my Aerocharger bit the dust.

It's a lovely new Holset

Holset - 1
Holset - 1


Holset - 2
Holset - 2


So what size oil restrictors are people running? It's plumbed into the main oil gantry, my concern is it stealing oil from the mains and big ends.

Cheers Mark


Shooter63 - 8/1/17 at 06:03 PM

It depends on what turbo you have, a ball bearing turbo needs a restriction a journal bearing type doesn't as a general rule ( gt and gtx are ball bearing turbos the T series are journal )

Around a 1mm restriction for the ball bearing type.

Shooter


mark chandler - 8/1/17 at 06:16 PM

Holeset journal bearing, I do not believe the turbo requires a restrictor to run, I am more concerned about it bleeding off oil from the engine. Thanks for the reply maybe I should rephrase the ask, has anyone suffered low oil pressure when running a turbo without a restriction in the turbo feed ?


Matt21 - 8/1/17 at 08:29 PM

If the turbo doesn't need a restriction can you not just fit an oil pressure gauge to keep an oil on things? (even two, one at the engine and one at the turbo?)

As long as there is enough oil volume to fill the turbo and hoses/cooler etc on top of the volume needed to feed the engine I cant see there being a problem. Unless I have got the wrong end of the stick?


CosKev3 - 8/1/17 at 08:31 PM

I thought bike engines need a restriction in turbo feed lines due to the high oil pressure a bike engine creates at high revs?

I've fitted a 1.5mm restrictor in the turbo on my R1 engine after seeing someone use the same on a R1 bike turbo conversion

Mark,did you not use one on the old turbo?

[Edited on 8/1/17 by CosKev3]


Shooter63 - 8/1/17 at 08:44 PM

Sorry I didn't see that you have a holset, presuming that your engine has around 70psi a restriction might be a good idea, by the way what type of holset have you got, 221, hw27? If so what size housing have you got 4cm 5cm ?


Shooter


mark chandler - 8/1/17 at 08:47 PM

The old turbo was self contained with its own oil bath and ceramic ball bearings, the bearings failed and to fix it was eye watering, given the limited number of miles it covered - at most 200 I have dumped it, it was second hand.

I may try a couple of mm then and see where that gets me, thanks


dave_424 - 8/1/17 at 10:32 PM

I run an unrestricted -3 line into a TD04 turbo, works great


mark chandler - 9/1/17 at 07:23 PM

quote:
Originally posted by Shooter63
Sorry I didn't see that you have a holset, presuming that your engine has around 70psi a restriction might be a good idea, by the way what type of holset have you got, 221, hw27? If so what size housing have you got 4cm 5cm ?


Shooter


Its a billet HE200WG

from here

http://www.compressorracing.com/our-turbos.html

Holset HE200WG 320bhp billet turbo. HE211W HE221W. Not Garrett GTX28 GT28 T3 T28

Large alloy Holset compressor housing with 3.5in MWE (Map Width Enhancement) ported anti-surge inlet and 2in (ID) v-band outlet flange.
Lightweight high flow billet allow MFS Holset 6 blade compressor wheel with 41mm inducer proven capable of 32lb/min flow and 40psi+ boost.
Oil cooled core with 360deg thrust bearing and heavy duty shaft.
47mm 11 blade quick response turbine wheel with 41mm exducer.
Super quick spool 4cm turbine housing with integral wastegate

Ripped up an exhaust flange from some 3/8" plate

Hoping it should deliver the goods, looks nice anyway!


mark chandler - 15/1/17 at 12:31 PM

Finally fitted up the turbo, hard oil feed line and return to the sump done

What is quite extrodinary is the effect oil has on the spinning of the turbine, watch the turbo at start up idle and it spins merrily, then the oil pressure builds and it almost stalls it with a 3mm reduction in the feed line.

I will run this for a while as its a nice new turbo as it beds in then look to reduce to maybe 2mm to,lessen the effect.

On idle it makes a little pressure, blip the throttle and I get a nice surge so it is looking very promising, the exhaust noise has also greatly reduced.


CosKev3 - 15/1/17 at 01:34 PM

So you've got 1mm hole feeding the turbo?

Do you have to run a scavenge pump on the return?

Any pics of how high the turbo is mounted compared to the oil level in engine please?


mark chandler - 15/1/17 at 02:55 PM

I filled the banjo with weld and drilled a 3mm hole in the middle, this banjo is hard line on top of the turbo.

No scavenge pump on the return, it just goes to the sump, below oil level so I will find out if that's okay when it is run up properly.

Packaging is a problem on our cars keeping the turbo high, there is around a 2" drop.

[Edited on 15/1/17 by mark chandler]


CosKev3 - 15/1/17 at 03:04 PM

Ah I see now,you are thinking the 3mm is too big/too much oil?

Yeah hard on a bike engine to get it high enough for the return to just use gravity.

I'm putting a scavenge pump on mine whatever


mark chandler - 15/1/17 at 03:14 PM

Yes, I can restrict the feed down if required as cold oil it also slows things down anyway.

It can bed in the bearings for a few hours, I will then try a 2mm hole if I get a big delay in spooling, the old turbo had ceramic bearings and you could here that running down for 5 seconds after you turned off the engine, this one stops immediately.

I want to see 200 +HP from it whatever