Oil Supply to Turbo
 

Finally getting to the finishing stages of installing a 99 engine and turbo in my 91. Basically had the oil feed plumbed from the right side feed I've seen most often, when my son asked why didn't I use the oil feed at the left rear of the head. Good question I said. A lot closer to turbo, shorter lines etc.

My question is, is there any downside to this? ie, the feed from the head comes after a restricter in the block. Is there enough oil there to feed cams, lifters AND the turbo? I never really thought about it, but how much oil does a turbo really use? This install is a small Garrett with sleeve bearings.

There are 2 or 3 threads just recently where we discussed this.
Search around.
Here's one of them:
https://www.miataturbo.net/diy-turbo...ey-plug-75112/

The conclusion is no one knows for sure, so attempt at your own risk.

By the way, I now have all tubes and fittings and plan to do my pressure testing that I promised tomorrow. Pressure vs RPM curve on that head port with no outflow, and with turbo.

I may use that plug as well...considering most turbos need some sort of restriction it may be an ideal solution.

YES PLEASE!!

That would be awesome.

Thanks

+Juan

Great - Thanks for that link. Seems a lot of us are in the same boat, ie, a bit skeptical about pulling oil from the head. That restrictor in the block has a dang small hole in it, but what I've seen was on older (pre 99) engines I've done. I haven't actually seen the restrictor in the block of the 99+ 1.8 to see if they've done anything different with the solid lifter cars.

Well, for now I guess I will stick with that port on the intake side. Like some, I was also concerned about the weight of stuff hanging off the tee - so I've got the pressure sensor mounted to the car on the end of a hose.

I know that the restrictor in the '99-'00 block is the same as in the '90-'97 block.

I cannot speak to the '01-'05, however I assume it's the same, since the VVT mechanism has its own dedicated feed.

What Joe says is what I was explaining to you the other day. 18psi linked you that thread I was discussing with you.

I say we go for it. It's not my head. :rofl:

HA HA - "WE" go for it!. You are quite right - its my head ;) We can do that if "we" put a turbo in your car. Meantime, I just can't see how enough oil can get there.

In the meantime, get well and I hope to see you at the shop in the morning.

its past "tomorrow"

any results?

Today is yesterday's tomorrow.

https://www.miataturbo.net/attachmen...1&d=1386555525

I posted the results and my comments in the thread where the promise was made:

https://www.miataturbo.net/diy-turbo...-supply-75631/

As expected, oil pressures are lower, and affected by flow. I am going to run head port for my TD04, and think that restricted flow to BB turbos would be OK as well.

Other research indicates that many other engines also use restrictors going to the heads, and factory turbos on those cars use the head ports for supply.

DNM

I am using this plug and a -3 line and havent had any problems.

I know the main discussion about this in the other thread, but I disagree with your comment if its being used as justification to pull from oil from the head.

A factory turbo car has an oil restrictor designed with turbos in mind. A non-factory turbo car did not however. What would be interest to see is what Mazda has done with the BP in turbo applications. I am pretty sure the oil feed for the mazdaspeed miata is from the block. Not sure about non US-market protege turbos that used the 1.8, the mazdaspeed protege, or any other application of the BP with a turbo from factory.

It would be cool if we could info on the restrictor used in those application and where mazda pulled the oil from.

In any case, I will take a look at your thread.

the MSM indeed does source from the block.

but then the MSM has a lot of really stupid things done to it as afterthoughts, so I'm not entirely convinced that proves anything.

In the 323GTX (both the B6 and BP versions, and regardless of market), the turbo oil supply was from the block, using the same port (near the flywheel on the exhaust side) that was preset in the early Miata engines.

The removal of this port from the Miata engine coincided with the discontinuation of the 6th gen Familia / 323 and, with it, the discontinuation of the last factory-turbocharged B engine of that era.

Joe can you comment on this:
https://www.miataturbo.net/diy-turbo...-supply-75631/

post 17 and on.

I know its like a limited production joint effort between aftermarket/mazda but mazda was still somewhat involved.

It keeps tempting me

well, the evidence there. I think people can pull their own conclusions. This is not like a coolant reroute for example, where Mazda had an original method, then tried a new configuration, then changed it multiple times in an effort to deal with a symptom.

It seems consistently Mazda has used the block port, not the head. Not saying that your engine will go boom if you diverge, but its probably the more "reliably safe" location to get oil for a turbo. It is also very possible the head port has enough tolerance to accommodate a turbo... *shrug* gotta try it out ;)

Yeah, I saw that, but I've already weighed in on a couple of the "which oil feed" threads this month, and I just didn't want to get into a pissing contest with an Aussie who was hell-bent on proving a point.


I don't have any empirical evidence to prove that taking oil from the head is a "bad" thing. All I can do is point out the fact that B engines run their cams directly in the head casting with no bearings, and that there's an oil restricter between the block and the head which I assume Mazda calibrated for the oiling demands of the head all by itself, with no turbo. Further, I read the fact that Mazda started drilling that hole in the block again on the MSM, after a 10 year hiatus, as evidence that they also felt that taking turbo oil from the block was potenially less risky / more reliable than taking it from the head.

I'm sure this isn't a binary deal, like "if you take turbo oil from the head, your engine will immediately explode." My guess is that, like forced induction in general, it's just a matter of degrees. Like if you take away 20% of the oil from the head, you will reduce the useful life of the [head / cams / followers] by xx%.

It only costs a few bucks extra in hose and fittings to source turbo oil from the block on a post-94 engine. And given that this is what both Mazda and the major US and Japan-based aftermarket suppliers (the ones who offer warranties on their kits) do, I will continue to recommend this practice.

But I'm not going to waste my time arguing about it with people who have something to prove.



That's exactly the correct way to look at problems such as this one; which solution presents the least chance of causing a problem.

And yet in post#18 you can clearly see that Mazda of Australlia used the head port on the limited edition turbo 01

You know...I wrote a long message about engineering, over engineering, and product life, etc. but I don't think it matters. Like I said before, pull your own conclusions. No one said your engine will blow up for using the head port, just that its probably maybe possibly better to get it from the block.

Also, mazda Australia is not the same company that built the miata and mazdaspeed miata.

lol

I know.

I'm trying to persuade myself but am just as torn as I was when I first considered it. The reason I keep bringing it up though is because I'm actually faced with this decision right now. I need to buy and install an oil feed line on my current setup, and have gone back and forth like 1000000x times on which route I want to take.

The only reason I'm considering the head port routing is because of how clean and simple it is. You can do a 90* off the port going up, then clamp the line to the valve cover bolts, then straight down into the turbo. Total 20", totally secured, really clean, really simple, vs running a huge 46" line all the way around, wrapping it in stuff so it doesn't rub or cut anything, etc etc etc.

I know, I'm just being a drama queen. :giggle:

VVT line yo. But be more of a man than me and cut and flare the hardline going across the the VC and put in a T.

Yer definitely being some kinda' queen. :giggle:

https://www.miataturbo.net/attachmen...ine=1387379397

https://www.miataturbo.net/attachmen...ine=1387382871

https://www.miataturbo.net/attachmen...ine=1387382871

https://www.miataturbo.net/attachmen...ine=1387382871



From last week

Same location as that used by the designers of the fastest factory miata ever, which uses a tubular style cast manifold with a GT2560r and a 2.5" exhaust.

What more needs to be shown or said?

Dann

/\ That's EXACTLY what I was thinking of Dann.
That looks great.
Thanks for posting that. Props

:party:

It is a VERY neat setup, I probably prefer the hardline, which is also a LOT cheaper, but there is no doubt the silver on black braid is really super nice done like this.

Dann

Hold on here, you are calling a Aftermarket developed car under the oversite of Mazda Australia's motorsport division a factory car? I think you need to rethink the word "factory". This was (probably) not developed under the oversite of Mazda Engineers, and definitely not the Mazda Engineers who developed the miata, or the BP engines originally.

Stop trying to act like you have hard evidence in this [highly speculative] argument/discussion.

This Aussie thing is a bit like a Brabus Mercedes or a Yenko Camaro. An aftermarket modification carried out with some form of blessing from the local authority, but both designed and manufactured outside of the auspices of the original design engineers and the OEM factory.

As such, they exist in a sort of murky middle ground. From a purely legal point of view (eg: in a Tort case), such modifications are authorized by the manufacturer's agent (the dealership), and thus occupy the same status as OEM. From a technical point of view, these modifications are no different from a kit designed by any other third-party (eg: Bell, BBR, Greddy, Flyin' Miata, Jackson, Knack Toys, etc.)

Is it a "factory turbo" Miata? Well, to the best of my knowledge, the only Miata factory is located in Hiroshima, Japan, and that's not where these turbocharger systems were designed or installed.

Here is my take, based on my research, and in part from comments by in this FAQ:

Forced Performance Turbochargers

Basically it comes down to how much oil an individual turbo needs. Since I am installing a TD04L-13T, I believe that the risk is minimal, and I'm willing to take it. I will hedge this bet by moving to 0W-40 synthetic oil, rather than 10W30.

However, there is no doubt in my mind that the block feed is more safe and sure from the motor's perspective. It is fed directly from a regulated supply, that should automatically account for the increased flow, whether small or large (within the capacity of the pump).

As far as comparisons to Factory, what are we doing that is even close to what factory (Porsch not included) is willing to do.

18PSI, you just have to make a call and go with it.

If you go with the head port, you could temporarily put a Tee at the port and monitor the pressure in the head and going to the turbo. Maybe get Brain to hook you up an input on the MS3 and use an analog sending unit with an alarm. Then, after a few months, jerk out the Tee and sensor and be happy, or move the oil feed to the block and be happy, depending on how it goes. Like Joe said, it's not likely going to be a quick, catastrophic mistake.

I mean, if you go with a block feed, are you not going to have to experiment and risk issues while you determine the correct restrictor orifice? Too small, burnt turbo, too large, blowing oil, etc. Just off the top of my head thoughts.

Two answers:

1: No, enough thousands of people have already done this that the variables are well-understood, and the requisite parts are cheaply available off-the-shelf from multiple vendors.

2: Any hypothetical trial / risk which would be associated with the above (if no one had ever done it before) would still exist in a head-feed setup, and would merely be added to the hypothetical risks and uncertainties associated with depriving the head of oil.

Joe, Fair enough, and well stated.

turbo oil restrictors are generally suggested by the manufacturer.

Last time we are going to bring up this Aussie turbo miata...

ITs built directly on a 2002 LS miata. it uses a straight up VVT motor which didn't even have a port on the block (like the MSM & 94). So unless the aftermarket guys are planning to hack shit up DIY style like us, its not possible for them to use a block port anyway.

I am willing to bet that they looked at it as:
"hey this car is going to be warrantied much less than a regular miata, so fuck it"

Or maybe they did their due diligence and called up Mazda Japan and said:
"Hey, can we pull oil from a head port on miata?" to which Mazda Japan said "Sure, especially since its a VVT BP motor with a bigger oil pump".

You're probably right, except for this part:

It woulda been just as easy for them to tee off the oil pressure sender just like we do.

Again, I'm not defending either way because like the rest of us, I have no idea on the logistics of this issue.

I understand, but that seems less "clean" to having a dedicated port.

Is that a 20" line?

I can find out. Isn't your turbo going to be in a different spot anyway?

Dann

That looks like a tubular begi/fm replacement. In which case it should be in exact same location. I'm switching to another setup. Again lol

Yenko is a poor comparison. In 67/68, he was taking a completely factory iron 427 (the L72 motor) and dropping it into L78-equipped Camaros. It's akin to Mazda Australia dropping a 1.8 into 1.6 chassis using all factory electronics - not really much design work going on. In '69, Chevy themselves actually manufactured the cars on the production line as COPO 9560 (aluminum 427) and 9561 (L72 iron 427), so there's literally no design/manufacturing beyond the original design/OEM factory.

[/nerd]

In this case, it's adding a turbo to a motor which never came from the factory with one (until the MSM, which got a much smaller turbo and, more to the point, used a different feed location which Mazda had to spend money to recreate on the later NB2 blocks). Apples and oranges.

So what's your take on this discussion Sav?

As clean as the head port is, I don't like it. The head is fed through a fairly small orifice, so the pressure/flow is already restricted, and pulling from that doesn't seem like a good idea (and the data that DKMakinson posted backs that up).

There's also the fact that Mazda went through the hassle of re-drilling and re-tapping those ports in the block when they did the MSM, instead of just pulling the oil from the head. We'll be sticking with a block feed for our kits.

For the VVT block that doesn't have a pre-drilled port like earlier engines, I still wanted to feed the turbo from a source as close to the oil pump as possible (so, not from the head).

I looked at teeing an adapter under the oil pressure sender but didn't like all the pipe thread ports, and the resulting extra-super-cantilevered sender looked like a disaster waiting to happen. Hokey, kludgy shit.

So my solution was to make a different banjo bolt to replace the stock one that secures the VVT oil pipe to the block. My banjo bolt is identical except it has a -4AN male port protruding from the hex.

Bingo, a clean, bullshit-free turbo oil supply solution that's close to the oilpump yet still sources oil from downstream of the oil filter.

(As an aside, or more fuel for discussion, Keegan frowned at the factory oil port location on the driver side of the block since this galley location diverts oil directly from the rearmost main bearing. So there's that...)

Mazda used that location on thousands of factory turbo vehicles. Everything from the 323GTX to the MSM used that port AFAIK. Keegan is going to have to come up with a lot more than "I don't like it" to counter that kind of empirical data.

Believe me, I hear you. Just passing along the observations of someone who spent a big chunk of his career building Champcar & Nascar engines. His take was more along of lines of: "why deprive the rearmost main when you have an alternative?"

I found that logic hard to argue with.

It's a custom manifold, I have never seen a begi or FM mani in real life.

Dann

I find that logic easy to question, particularly when the alternative is to deprive the head.


The #4 main bearing is fed by a passage only a few inches off of the main oil galley, which is extremely large in diameter- around 1cm, if I recall correctly. There is relatively little restriction in this path, and the amount of oil drawn by a turbocharger as a percentage of the capacity of that passage to supply oil is quite small.

By comparison, the entire head (10 bearings and 16 lifters) is fed through a single, restricted port which is smaller than the port feeding the #4 main bearing. The oil flow through a turbocharger as a percentage of this flow is much larger.

Claiming that a turbocharger is going to deprive the #4 main bearing of oil is like claiming that sucking water out of the Mississippi river through a drinking straw will cause its level to drop. Technically true, but so incredibly insignificant in magnitude as to be entirely dismissable in practice.

The oil supply to the VVT is in the block just off the main galley, between the #3 and #4 mains, and upstream of the restrictor.

Ok. And the relevance of this is... what?

F2T has the same location, for whatever that's worth.

Uhm, that's where I sourced the oil supply for the turbo.

I understand you already said you don't want to end up in a pissing match with me Joe, but hear me out.

I understand the restrictor thing, and we should find out if the HLA cars have the same sized one as the solid lifter cars, because this would tell you pretty quickly that it's definitely good for the solid lifter cars.

I just wanted to point out that the head is under so much little stress than the big ends it's not even funny. If you have ever oil starved a BP, and I have twice, you would know that the head doesn't even care and the very first thing you flog is the number 3 and 4 big ends. The forces in the head are completely laughable compared to your regular 200-250whp turbo miatas big end bearings. We are talking about a hardened cam on a hardened lifter which in the case of solids just needs to be a bit wet with oil on top. Not requiring any pressure at all.

Each cam has 6 bearings each as wide as the rod bearings, and the forces are so low that with the cam belt off and NO oil pressure you can easily put a 4" long spanner on the cam gear bolt and turn them with a finger or 2.

These are just points for consideration.

Dann

There is no "cam bearings" in a miata head...unless you are referring to the casting that the cams sit in (you can't remove those like a conventional bearing). Just clarifying here...

Ah, Gotacha. I thought that this was meant to be relevant to the question of the stock oil outlet on the block vis-a-vis the #4 main bearing.

Yes, I'm sure that the VVT outlet is also a find place to take the turbo oil from, functionally comparable to taking it from the oil pressure sender as is commonly done on the '95 and later Bell / FM kits.





I really can't see how this is relevant. Under normal operation, the amount of oil "consumed" by the hydraulic lifters is nearly zero. Once they're pumped up, they require a significant pressure but very little volume to remain "full."



I'm not sure why I can't quite seem to see things from your point of view, but from where I am standing, the volume of oil consumed by the turbocharger, relative to the capacity of the main oil galley and #4 main passage to supply oil, is trivially insignificant. I'm sure that, in actual practice, the rearmost galley in the head is also capable of supplying a sufficient amount of oil to satisfy the needs of a turbocharger, however the safety margin at this location is simply going to be much lower. That's all.

Insomuch as this location is the alternative that addresses any concerns (no matter how small/perceived, etc) associated with that stock oil outlet on the block, it seems pretty relevant.

BTW here's a pic of said VVT banjo tur-bolt. Stock one on top:

https://www.miataturbo.net/attachmen...ine=1387666100

JKav: Is that the block banjo bolt (PN 9YA3-51-001C) or the upper banjo bolt (PN 9YA3-41-601) that connects the 2 VVT oil feed lines together?

I'm also guessing you made that as a custom part that I can't just order from somewhere...

Thanks!

That banjo bolt is slick as shit. Will that fit the upper banjo that'll give a shorter line. I'm not 100% happy with the cleanness of where I tapped into the VVT connector.

Just curious, would a double banjo bolt setup work for the vvt oil take off?
https://www.miataturbo.net/attachmen...ine=1387669959

Interestingly the IL motorsport kit uses the head port to feed the tubro on its 1.6 NA kits.
http://www.ilmotorsport.de/shop/get_...cc20f7e350d8d6

Have there been reported failures attributed to using the head port?
It is not ideal..... but is it good enough?

That's really the key point in all of this.

It obviously works "well enough," and is hugely unlikely to cause any catastrophic failure. Any damage resulting from this setup, were it to occur, would be extremely gradual and most likely masked as ordinary wear.

The question then becomes- is it worth taking the chance just to save a few feet of hose and a tee fitting?

Block. Yeah, custom.