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Oil feed from filter housing for MHI turbo. Should I add a turbo oil filter?

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dsm-onster

DSM Wiseman
8,592
130
Jul 11, 2004
Bloxom, Virginia
Well, the MHI 14b 16g turbos seam to do fine w/ a head fed oil line. So these turbos don't seam to need the astronomical oil pressures that other journal bearing turbos love.

Considering many have plumbed from the filter housing and have had no ill effects, I thought that I'd try it. Cleaner, cooler oil. Has anyone added a turbo feed line filter to a 14b/16g/18g/20g? I have one lying around from my 60-1 turbonetics. I have a braided stainless line from the housing and the adapters to connect it to my small 16g. Am I being overly cautious? or is it a good idea? Has a oil filter lowered the oil pressure too much for some? I've never used a feed from the filter housing for a MHI unit. . .
 
I don't think it would but might not be a bad thing if it does depending on your oil pressure/size if feed line, I was going to suggest a restrictor if your BS has been removed. I would however, keep it at the head location, I ran my 16g from the head for over 60k miles without any issues.
 
There's no real need for a turbo oil filter. It's just more gee-whiz crap to sell the kids and impress the clueless. If your oil system is circulating crap, you're in for more problems than a turbo bearing.
 
I've run my MHI turbos for years at the head too. But I have all the parts here lying around. And I'm a hoarding pack rat. I don't see why it would be a bad thing to run it from the filter housing. It could only help, right? assuming the pressure to the tubo is in the proper range.

My rs60t went out and this is the same braided line and filter. I've verified that the filter and line were in good flowing shape. And the rs60t has shaft play enough to contact the housing but no oil seal issues. Considering those turbos just break for no apparent reason, I'm pretty sure the line and filter are in good shape for this.

FWIW, none of my balance shafts are removed, but I am not running a BS belt. I've not seen anyone's oil pressure measurements for my case. Most are getting 60-80 psi during spirited driving with both balance shafts spinning. What is a typical head feed measurement in boost? I've seen 1 or two posts w/ reports of 30-40 psi. I don't have a oil pressure gauge. So I'm concerned about adding the filter. I just don't want to put the oil filter on there and it restrict the flow too much and kill the turbo. I'm being a little pessimistic. Or perhaps just a pest.

I've done the backyard flow test:D and blew through the turbo filter and blew through the metal head line. The filter seams to be little more restrictive. But I am doubting the oil pressure would be cut in half from the flow restriction, right? And if so this is the operating rainge from MHI units fed from the head, anyway. Just trying to fix something here that's not brokeLOL .
 
There's no real need for a turbo oil filter. It's just more gee-whiz crap to sell the kids and impress the clueless. If your oil system is circulating crap, you're in for more problems than a turbo bearing.

HA! that has to be true. there are alot more bearings in the enginebay that the turbo bearings! Maybe, I'll just run the line from the housing w/out the turbo oil filter. I've heard of reports of slow spool w/ too high of an oil pressure in journal bearing turbos. If my spool seams sluggish then I'll add the filter. . .
 
Primarily I'm concerned about oil flow/pressure not really oil debris. This thread is what has me wondering about too much pressure: Slow Spool on the 2.3. Of course, I'm concerned about too little pressure. . . I suppose this won't be an issue. But I wanted to ask the question anyway. But, more importantly, do MHI units suffer from poor spool if the oil pressure is too high, like garrett units?
 
Stop overthinking it. You just run a line right from your filter housing, no porting, no filter, no messing and it will be just fine. There is a major advantage in running it from the filter housing in cleaner oil quicker oil pressure after startup, and cooler oil/more pressure.
 
Why fix something that aint broke? :)

I have always worry more about high pressure than low. In fact, my 16g died due to a frozen vented catch can which lead to excessive crankcase pressure and higher oil pressure in the CHRA. There are simply too many examples of new hybrids blowing smoke after few miles due to high oil pressure while feeding from the filter housing. I do not know if this applies to MHI turbos but I do know the head location has been proven with MHI's. IMO the only situation that requires feeding from the filter housing location is when running a dry turbo.
 
IMO the only situation that requires feeding from the filter housing location is when running a dry turbo.

Good point. One reason why I am interested in feeding from the oil filter housing is for having cooler oil. But, the bearing heat is handled w/ the wet bearing housing. Oh well. I guess there's no sense in changing the manufacturer's design on this aspect.
 
FWIW, none of my balance shafts are removed, but I am not running a BS belt

Just curious but I thought this was not a good idea to just take off the belt and not remove the shafts.
 
I've run w/out the bs belt but w/ the balance shafts for over a year now. No issue. Have you had any issues? The bs assembly cancels out the vibrations that make their way to the uni-body and consequently our glute by sending a negative wave to the block. That keeps the vibration "localized".
 
I've run w/out the bs belt but w/ the balance shafts for over a year now. No issue. Have you had any issues? The bs assembly cancels out the vibrations that make their way to the uni-body and consequently our glute by sending a negative wave to the block. That keeps the vibration "localized".

No I still have my belt and shafts still in place. I thought I read somewhere that if you dont remove the shafts then you lose oil pressure. If there are no ill affects when I take my head off to be built I will probably just take the belt off.
 
actually the oil you take from oil filter housing - is pre oil filter, so its not filtered - thats why to put an oil filter is a good idea
Your thinking wrong bro.

The oil that you get from the oil filter housing is filtered, and it's going to be the cleanest. That's why several DSM shops recommend that you run a oil feed line from the oil filter housing, such as my FP Green from FP. They recommend running there SS oil feed line straight from the oil filter housing because it's cleaner:)
 
And yes, it will be dirty if you go from the wrong port on the oil filter housing, there's two, one for filthy crappy already run through your whole motor oil, and one for fresh clean just out of the shower oil.
 
Most oil feed lines that you purchase from vendors will be the ones that are suppose to be installed after the oil has been filtered, especially on turbos that are oil fed only.

The only other way is running the oil feed line from the head, and that won't be as clean.
 
Your thinking wrong bro.

The oil that you get from the oil filter housing is filtered, and it's going to be the cleanest. That's why several DSM shops recommend that you run a oil feed line from the oil filter housing, such as my FP Green from FP. They recommend running there SS oil feed line straight from the oil filter housing because it's cleaner:)

Correct! There is a good reason why 2nd gens get oiled from the filter housing.
 
No I still have my belt and shafts still in place. I thought I read somewhere that if you dont remove the shafts then you lose oil pressure. If there are no ill affects when I take my head off to be built I will probably just take the belt off.

If you lose the balance shafts all together, then your oil pressues goes way up. If you run w/out the belt (and keep both balance shafts) the oil pressure remains about the same.

I've seen no ill effects for a LONG time now.
 
The purpose of removing the balance shafts is to prevent BS bearing failing and take out your entire engine, especially on a expensive re-build revving to 9k rpm (think crank : oil pump gear/BS pulley ratio), leaving in your rear shaft defeats the purpose of BS removal (only thing you achieved is saving $30 on the BS belt), not to mention the vibration this will create. It's fine to leave the front shaft in place without the belt but the rear must be replace with a stubby shaft.
 
Remember that your balance shafts spin at twice the speed of the engine! at 7,000 rpm your 20 year old balance shafts are spinning at 14,000 rpm.
 
When I install my forged rods/pistons, I will be doing the removal or the cut-rear-shaft mod mentioned by the vFAQ:

"Another mod some people have been doing (being more paranoid than even me) for very high revving engines is a modified rear balance shaft. They basically chuck the rear shaft in a lathe and cut the balance weight off of the shaft. The advantage to doing this is that the oilpump shaft is fully supported in the oilpump case and farther back in the block. Personally, I don't think this is necessary for the average DSMer, but if you plan on winding your engine above 8000rpm, it might be something to consider."

The rear BS bearings stay, but they are not under the sideload of a heavily unbalanced shaft. If you know a guy w/ a lathe, this is also more affordable.
 
It really looks like garrett and MHI turbos like the same oil pressure. Here's a good post clarifying optimal turbo oil pressures and related accessories:


So the question is for you garrett guys: do most of you run 0.078" (5/64) restrictor and plumb from the filter housing?

Don't most 2g 14b/16g install kits come w/ a restrictor? What size is this? I am thinking about a 1/16 restriction (0.063) to 5/64 (0.078).

Bruce, I'm just stuck on running from the oil filter housing:p . Besides, I lost my turbo side banjo bolt for the feed line the other day:D . If I have to buy anything, I could buy a restrictor to keep the pressure optimal and plumb from a better oil source. Wouldn't that be a sensible alternative (if one already has the ss line and fittings for the filter housing feed)?
 
Lotta good points here on Turbo Oil supply & I'm not so sure there is a right or wrong - I personally don't like the long run fm the OFH & I'm hence specifically going with a upgraded Turbo that likes Oil Feed fm Head - I AM SURE that deleting the Rear Balance Shaft with the Stubby Shaft should be a BIG priority for dsm-onster, leaving that Rear BS Shaft in is WRONG - PERIOD.
 
Hmmm, longer route? What's the distance the oil travels from the filter housing to the turbo through the engine vs. the distance the oil travels to the turbo through a ss braided line?

Most guys wanting to run high rpms like to keep the rear BS in and cut the counter weights off of it. This is what i'm going to do. The oil pump shaft will be better supported but free from the sideloads caused by the counter weight (which leads to bearign failure in high reving situations). I want my 2 X RPM spinning oil pump to remain in one piece as I take my engine to 9K.

I'm thinking that 1/16 to 5/64 (.0625-.078) restrictor diameter off of the filter housing will bring the oil pressure down the proper pressure for a MHI unit where an engine is experiencing factory engine oil pressure (no bs removal). Does anyone have experience w/ this?
 
You'll definitley get more pressure from the oil filter housing. :)

FP recommended that I run my line from the oil filter housing for more pressure, and cleanliness when I purchased my FP Green, but the Green is oil fed only in which I'm sure you know that.
 
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