FA20 Engine Oiling, Bearings, and Starvation

[Dezoris]

Originally Posted by Element Tuning

It's a simple device that has it's place but has some shortcomings which with the right company can send you off with very little downsides. A dry sump is superior but comes with a superior price tag and has its own shortcomings for street cars.

We have figured out a solution with our internal engine mods and when coupled with some off the shelf products like a Perrin Oil Cooler and an accumulator (lots of brands) I can sell engines with a clear conscience now.

Next an external oil pump for more serious racing and HP users (keeping AC is my goal) prior to going dry sump.

Thanks,
Phil Grabow

I spent the past two months now looking at oil temp/pressure data on three cars now.

We have an annoying issue to contend with here as for users who deal with cold weather mean colder starts are very difficult when you have 125PSI oil pressures and 10-15 minute oil warmup times to get pressures and temps normal.

That rules out "thicker" oils for daily drivers in my opinion.
But your findings follow what I am seeing. As temps climb pressures drop.

On the 9PSI Vortech with Perrin Cooler:

At oil temp of 200F:
Pressure 58-60PSI @7000RPM

At oil temp of 210F:
Pressure 55-57PSI @7000RPM

At oil temp of 220F:
Pressure 46-47PSI @7000RPM

At oil temp of 230F:
Pressure 45-46PSI @7000RPM

At oil temp of 240F:
Pressure 40-42PSI @7000RPM


Stock Motor No Oil Cooler:

At oil temp of 200F:
Pressure 62-64PSI @7000RPM

At oil temp of 210F:
Pressure 60-61PSI @7000RPM

At oil temp of 220F:
Pressure 56-58PSI @7000RPM

At oil temp of 230F:
Pressure 55-56PSI @7000RPM

At oil temp of 240F:
Pressure 53-54PSI @7000RPM

My concern is obviously for those who are running higher redlines. I talked with Bill from Delicious and he is running his tuning at 7800RPM redline because the car is making power. How many tuners are really paying attention to pressures as heat climbs.

Based on this info and some of yours Phil, I personally would not recommend anyone running FI to be pushing much past 7200RPM on the track as temps get passed 220F running 0w20 or 0w30. It just seems like most failures are tied to bearing skimming. And most users don't understand the factors that can lead to all of this.

Whats your feeeling on that?

[Element Tuning]

Originally Posted by Dezoris

I spent the past two months now looking at oil temp/pressure data on three cars now.

We have an annoying issue to contend with here as for users who deal with cold weather mean colder starts are very difficult when you have 125PSI oil pressures and 10-15 minute oil warmup times to get pressures and temps normal.

That rules out "thicker" oils for daily drivers in my opinion.
But your findings follow what I am seeing. As temps climb pressures drop.



My concern is obviously for those who are running higher redlines. I talked with Bill from Delicious and he is running his tuning at 7800RPM redline because the car is making power. How many tuners are really paying attention to pressures as heat climbs.

Based on this info and some of yours Phil, I personally would not recommend anyone running FI to be pushing much past 7200RPM on the track as temps get passed 220F running 0w20 or 0w30. It just seems like most failures are tied to bearing skimming. And most users don't understand the factors that can lead to all of this.

Whats your feeeling on that?

Well this whole thread is about the oil pressure issue and yes, unless you've done what I've done, which sorry guys isn't all bolt-ons, you're not going to see 70-75 psi to 8500 RPM like I am.

In summary of the basics I wouldn't run 0w20 under any racing conditions and I would step up to 10w30 even for NA applications. For street and NA 0w20 is fine and sure you'll get a touch more power a maybe a little better fuel economy. Don't forget oil viscosity ratings are done at 100c (212F) and not at 240-280F. You need a higher grade if you are going to be running that hot.

For cold start there is no issues with up to 50w/20w50 for any of the warmer months. For a Subaru engine 125 psi is the norm for cold start up. There is nothing inside this motor clearance wise that should freak you out about oil viscosity and I know this for fact as building race and high performance boxer engines is our business (we've measured all the internal clearances). In very cold months (sub 40s) I would not run a 20w50 but I wouldn't hesitate to run 10w30. Just run a high quality synthetic as they flow so much better than conventional oils of the same viscosity rating. Everyone should have an oil pressure gauge on this car if modded!!!!

I also find these 0 weight oils are just horrible at high temps in terms of viscosity most likely due to the polymers used to get the oil to flow like that. The more you stretch the range the worse it is so a 0w40 is not as good as a 0w20 at staying in grade.

Thanks for the oil pressure readings for the various temps. Those pressures are not an issue with a 200 whp car. I would say even up to 300hp those are just adequate. If you start dropping into the 40s, you are in trouble and I've seen it in my own car and I know a few others have reported the same. As you add power you need more oil pressure to keep the oil wedge in the rod bearings.

How much oil pressure we need exactly is still a question. I suspect we need more than we use in the EJ motors because the FA20 motor has rod bearings that are narrower (so more pressure per square inch and therefore more force trying to squeeze the oil wedge out). The asymmetrical rod however may reduce some of this force however so it could be a wash in the end. I will say low 50s oil pressure equaled a spun bearing on my car at 400 hp and 8k+ RPM.

It's really not all gloom and doom as you NA and low power guys, drop the cooler on there and thicken the oil without a worry. Pump gas supercharged or turbocharged in the sub 300 whp range, same deal. 300-350 is the same but you're on the edge at that point but if you don't have a build motor you should stop there anyway. For 400-600 hp we have a fix with the motor build added.

Now racing is going to be the big question mark and I will be the guinea pig to see how well we can hold oil pressure under extreme WOT conditions. Based on my experience in racing our engines I'm going to expect to lose 10-15 psi which is going to drop us into the 60s. This means 400 or so be reliable. If we want to see 500+ reliable we need to stay in the 70s+ all the time.

Thanks,
Phil Grabow

[Calum]

Phil,

Have you done any testing to see how much changing the viscosity changes the operating temperature of the motor? Most of my work with oil viscosity has been with hydraulics, granted. But with hydraulics viscosity can have a noticeable affect on operating temperatures.

The asymmetrical rod wont have any affect on where the pressures are exerted on the crank journal. They only change how the forces act on the rod bolts. Asymmetrical rod are considerably stronger in tension because they don't put tension directly on the bolts. To my knowledge, strength in compression should be a wash, though.

Do you think the increased journal diameter of the FA vs the EJ would be enough to offset the decrease in journal width? Having you calculated the projected areas to compare the two motors? If you have, would you mind stating how they compared?

I'm guessing you want to keep your build specs to yourself, but would you mind sharing the OEM bearing clearances?


Thanks again!

[cdrazic93]

Originally Posted by Element Tuning

If we want to see 500+ reliable we need to stay in the 70s+ all the time.

would you mind listing the fix in a parts list?

I know this sounds kind of simplistic; but if 400+ is reliable now (atleast should be @ 60PSI u 70PSI sounds like it would need a larger oil cooler, and bigger oil pan, i have a feeling the oil cooler and subsiquent larger amount of oil could account for an extra 10PSI.

[Dezoris]

Originally Posted by Element Tuning

In summary of the basics I wouldn't run 0w20 under any racing conditions and I would step up to 10w30 even for NA applications. For street and NA 0w20 is fine and sure you'll get a touch more power a maybe a little better fuel economy. Don't forget oil viscosity ratings are done at 100c (212F) and not at 240-280F. You need a higher grade if you are going to be running that hot.

For cold start there is no issues with up to 50w/20w50 for any of the warmer months. For a Subaru engine 125 psi is the norm for cold start up. There is nothing inside this motor clearance wise that should

I also find these 0 weight oils are just horrible at high temps in terms of viscosity most likely due to the polymers used to get the oil to flow like that. The more you stretch the range the worse it is so a 0w40 is not as good as a 0w20 at staying in grade.

Thanks for the oil pressure readings for the various temps. Those pressures are not an issue with a 200 whp car. I would say even up to 300hp those are just adequate. If you start droppi
How much oil pressure we need exactly is still a question. I suspect we need more than we use in the EJ motors because the FA20 motor has rod bearings that are narrower (so more pressure per square inch and therefore more force trying to squeeze the oil wedge out). The asymmetrical rod however may reduce some of this force however so it could be a wash in the end. I will say low 50s oil pressure equaled a spun bearing on my car at 400 hp and 8k+ RPM.

It's really not all gloom and doom as you NA and low power guys, drop the cooler on there and thicken the oil without a worry. Pump gas supercharged or turbocharged in the sub 300 whp range, same deal. 300-350 is the same but you're on the edge at that point but if you don't have a build motor you should stop there anyway. For 400-600 hp we have a fix with the motor build added.

Now racing is going to be the big question mark and I will be the guinea pig to see how well we can hold oil pressure under extreme WOT conditions. Based on my experience in racing our engines I'm going to expect to lose 10-15 psi which is going to drop us into the 60s. This means 400 or so be reliable. If we want to see 500+ reliable we need to stay in the 70s+ all the time.

Thanks,
Phil Grabow

Phil thanks for feedback, on my end really I want to just get an accurate guide put together from experienced people so there is less speculation.

[Element Tuning]

Originally Posted by Calum

Phil,

Have you done any testing to see how much changing the viscosity changes the operating temperature of the motor? Most of my work with oil viscosity has been with hydraulics, granted. But with hydraulics viscosity can have a noticeable affect on operating temperatures.

The asymmetrical rod wont have any affect on where the pressures are exerted on the crank journal. They only change how the forces act on the rod bolts. Asymmetrical rod are considerably stronger in tension because they don't put tension directly on the bolts. To my knowledge, strength in compression should be a wash, though.

Do you think the increased journal diameter of the FA vs the EJ would be enough to offset the decrease in journal width? Having you calculated the projected areas to compare the two motors? If you have, would you mind stating how they compared?

I'm guessing you want to keep your build specs to yourself, but would you mind sharing the OEM bearing clearances?


Thanks again!

Yes oil viscosity does impact temperature to a point and so temperature also affects viscosity. This was last year but I had a long talk with the oil guys at Joe Gibbs when I was racing the FRS at the Ultimate Track Car Challenge. They had a lot of questions for me as they were commissioned to design an oil specifically to deal with the FRS's high oil temps in boosted applications. We bounced a ton of stuff off each other and basically you need to keep your oil cool and you also need to keep your oil pressure high enough.

If you can get the oil pressure you need with less viscosity great, but if you can't, thicken it up! Now given the factory car with 0w20 hits 280F on the track, what does that tell you? The viscosity isn't the reason why it's running hot.

In terms of the asymmetrical rods and the overall design of the FA vs. the EJ, there is a huge difference. The rod design is used to add stroke to the motor and is offset along with the piston pin.

The FA20 crank has larger diameter mains but not rod journals and it's the rod journals that take the pounding. So the rods journals are just thinner and the stroke is longer (86mm vs 79 for the EJ) so that increases the stress on the crank due to higher piston speeds. I'm just not sure the effects of the offset rod and pin and how that directly compares to the EJ in terms of the stress comparison at the rod bearings.

Also don't forget the first part of this thread and the differences in the oiling to the journals.

[Dezoris]

Originally Posted by Element Tuning

Yes oil viscosity does impact temperature to a point and so temperature also affects viscosity. This was last year but I had a long talk with the oil guys at Joe Gibbs when I was racing the FRS at the Ultimate Track Car Challenge. They had a lot of questions for me as they were commissioned to design an oil specifically to deal with the FRS's high oil temps in boosted applications. We bounced a ton of stuff off each other and basically you need to keep your oil cool and you also need to keep your oil pressure high enough.

If you can get the oil pressure you need with less viscosity great, but if you can't, thicken it up! Now given the factory car with 0w20 hits 280F on the track, what does that tell you? The viscosity isn't the reason why it's running hot.

In terms of the asymmetrical rods and the overall design of the FA vs. the EJ, there is a huge difference. The rod design is used to add stroke to the motor and is offset along with the piston pin.

The FA20 crank has larger diameter mains but not rod journals and it's the rod journals that take the pounding. So the rods journals are just thinner and the stroke is longer (86mm vs 79 for the EJ) so that increases the stress on the crank due to higher piston speeds. I'm just not sure the effects of the offset rod and pin and how that directly compares to the EJ in terms of the stress comparison at the rod bearings.

Also don't forget the first part of this thread and the differences in the oiling to the journals.

How much oil pressure are you going to gain at redline with a 30w oil compared to a "thicker" 0w20 like redline.
I was doing some further testing today because we have heat and was seeing 48psi at 7k. Very troubling.

[Element Tuning]

Originally Posted by Dezoris

How much oil pressure are you going to gain at redline with a 30w oil compared to a "thicker" 0w20 like redline.
I was doing some further testing today because we have heat and was seeing 48psi at 7k. Very troubling.

Yeah unfortunately you're not going to get much of a bump in pressure with oil viscosity alone. Even with 20w50 I was peaking in the high 50s without the oil cooler and without internal engine oiling mods. Don't forget oil viscosity is rated at 195 F and not 240+ so if you are running that hot and only seeing 48 psi I would run Red Line 10w40 or 40w Race if it's a track car.

We are moving forward with the external oil pump and dry sump setup so we'll have a bolt on solution soon that won't require an Element Tuning engine build. I'm hoping to have this sorted in a couple weeks so we can race the car in September for Global Time Attack.

[Element Tuning]

http://instagram.com/p/r5sBnItvc5/

So finally I can really run the Element Tuning Pro Comp motor hard to 9k RPM, run after run. In this video I'm running right at 20-21 psi of boost on E85, FIC 1100cc injectors, DW300 fuel pump, Garrett 60 Trim, Hydra EMS, Perrin 3" cat-back exhaust, internal oiling mods, oil accumulator, and the Perrin Oil Cooler kit.

As you can see the oil pressure needle is between 60 and 80 psi running about 72 psi all the way to 9k RPM. This pull was done after many tuning pulls and the ambient temps showed in the 80s. Overall I'm really happy with the oil pressure stability while running as hard as anyone could on the street.

I wanted turn up the boost but she's running at 100% injector duty cycle with the 1100cc fuel injectors. I'll probably toss her on the dyno but I'm not sure what the next step should be for fueling so I can keep pushing things. Either a return style fuel system with an external regulator or maybe a jump to 2000cc injectors.

Thanks,
Phil Grabow

[MAPerformance]

I may or may not have watched that video 10 times in a row...

[350matt]

Originally Posted by Element Tuning

http://instagram.com/p/r5sBnItvc5/

So finally I can really run the Element Tuning Pro Comp motor hard to 9k RPM, run after run.

9K Blimey


is it just heavier springs to get this safely? or have you done any other mods to the valvetrain?

[Element Tuning]

Originally Posted by MAPerformance

I may or may not have watched that video 10 times in a row...

Me too, I love the sound. I'm totally getting tossed in jail as I just can't stop blasting around in this thing. It's just runs so good!

[JasperNoone]

Originally Posted by Element Tuning

Me too, I love the sound. I'm totally getting tossed in jail as I just can't stop blasting around in this thing. It's just runs so good!

Skip Gude, 355, Shady Grove, 28, and that whole general area. LOTS of enforcement recently.

[Element Tuning]

Originally Posted by 350matt

9K Blimey


is it just heavier springs to get this safely? or have you done any other mods to the valvetrain?

Besides the engine build and the oiling modifications etc. this engine package has our Big Valve heads.



Just valve springs alone won't allow the engine to make really good power that high in the RPM. We fit +1mm Ferrea valves, multi-angle machining on the seats, port the bowls, and upgrade the valve springs.