High oil pressure= slow spool ?

[Ho0ked]

Hello, My profile is up to date.
My question is - How much oil pressure causes slow spoolup ?

With my balance shafts disconected but not removed, my stock pressure gauge goes to about 3/4 of its range under 20 psi of boost.

My turbo is a slowboy G50 and since day 1 I've had horrible spool like 5k RPM to make 20 psi.

I know my intake is a limiting factor but I have also noticed other people on this site mention high oil pressure as a cause.

If this is so how would I lower that oil pressure ?, Some kind of restrictor in the feed line from my filter housing ?

Any advice would help I'll be getting my 3" intake and maft done in the next month so I am trying to hedge my bets and not be pissed if my spool is still over 4k to make 20-28Psi.


PS. when I did my buildup I never saw any info about needing to port my oil filter housing untill it was to late, I don't realy want to pull all that stuff back apart if I can help it.

 

[Ho0ked]

Thanks for the help.

Guess nobody has ever heard of this.

 

[marcmsj]

I doubt the oil pressure is what's giving you boost problems. Have you tried doing a boost leak test and/or checking the wastegate actuator if it's internally gated?

 

[drivemusicnow]

It's true that garrett bearings don't like high oil pressure, but 20psi at 5k rpm shows something else is wrong as well.

A restrictor in the feedline is one common fix for proper oil pressure to the turbo.

If I were you, I'd also check some other things out like doing a boost leak test, a compression test, and check your base timing.

 

[Ho0ked]

Thankyou for responding

I have done all those checks and other then a slight leak at the TB butterfly, all is well, compression is all above 165.

125k on the stock bottom end.

Now notice I have no porting and 3" short route piping and stock exhaust mani, o2 housing, and full 3" downpipe back exhaust. Not sure much of that would make a difference

I know the intercooler is huge, the pipes are huge, and some of my topside parts are restrictive, but I was, and am still surprised by 5k 20psi......

Now what I am hoping is the root of the issue, My turbo has a 3" inlet, and my intake pipe is the stock configuration, with hard pipe and a round filter adapted to the end, BUT, its barely 2" diamater where it meets the turbo

I am hopefull that my GM maft setup with a new 3" intake pipe will bring the spool down from 5k to 4k roughly, when I added my downpipe and highflow cat, as my most recent upgrades, that got me from 5600rpm ~20psi down to about 5k rpm~ 20psi..........


Any thoughts on how much the intake will effect my spool ? and since the other things all check out O.K. is there any other remote possabilities ?

yes the turbo pulls like mad, and yes I know its not in its sweet spot untill 25+ Psi.
The new intake is when i'll go for 25-28psi

 

[GVR4592]

It sounds like there is a problem with the turbo. You should be getting 20 psi by 3800-4000 RPM's.

 

[Ho0ked]

Even on a stock block no porting what so ever ?
I was told to expect 4kish without porting and 3" Intercooler pipes

Hmm, perplexing, the car is easier to drive this way then with that tiny insta spool t-25 but 5k is a bit to slow 3k-3500rpm would be good to me.

Well, I had asked my SBR rep when I order and installed all this stuff over a year ago and he said without porting and with my small intake pipe this 5k spool is to be expected....

Not sure what to do now as im now tired of this slow spool. I practicaly have to peel out off the line to get a descent start against someone. WTF

 

[DoyoFCT]

so let me understand this clearly... you have the bs belt removed? but the balance shafts are still in there? what is the purpose of that? to my understanding this is not ideal, and i would think it could cause vibrations just as if they were out of phase which can severely limit power output/spool etc. correct me if im wrong i guess. I would put the bs belt back on, or fully eliminate the balance shafts the right way.

 

[GVR4592]

Well, I had asked my SBR rep when I order and installed all this stuff over a year ago and he said without porting and with my small intake pipe this 5k spool is to be expected....

He's an idiot.

 

[Ho0ked]

so let me understand this clearly... you have the bs belt removed? but the balance shafts are still in there? what is the purpose of that? to my understanding this is not ideal, and i would think it could cause vibrations just as if they were out of phase which can severely limit power output/spool etc. correct me if im wrong i guess. I would put the bs belt back on, or fully eliminate the balance shafts the right way.

Here is some clarafication for you

1 shaft is belt driven right under the timingbelt, if this belt should go, which it does to some people it takes out the timingbelt causeing $$$$ damage.
the other shaft is gear driven off the oilpump.

My front shaft (belt) is still in place but turned to alow oil to pass through as normal.
My rear shaft is removed and capped off as per the kit for doing this that many shops sell.

Yes I get more vibration, but I also will never lose my timingbelt due to some other stupidly designed belt system, potentialy saving me $$$$
And the vibration becomes (to me and many others) a none issue after a couple weeks of daily driving I don't even notice it anymore. It is nothing worse then a built muscle car shaking, infact its much much milder.

These shafts effect nothing except the vibrations of the car, nothing to do with performance , all about preventative maintence for the sake of smoother idleing

 

[nightspeed87]

Port the relief valve to lower the oil pressure...
Not as hard as it seems, trust me I parcarasinated about this for 2 months and finally
did it and wished I did it sooner... Lucky your turbo isnt smoking at times like mines...
Also put a restrictor...

What manifold are you running, and do you have any cracks, exhaust leaks which may affect spool... Check for those, what about boost leaks? Does the turbo have shaftplay yet? Is your timing on where it suppose to be and do you got anything goin on for tuning? And if all that stuff checks off good then id say I dont know, something about that turbo making it drag then, and if not then you just need to go build a 2.4 stroker and get better spool .

 

[Ho0ked]

Port the relief valve to lower the oil pressure...
Not as hard as it seems, trust me I parcarasinated about this for 2 months and finally
did it and wished I did it sooner... Lucky your turbo isnt smoking at times like mines...
Also put a restrictor...

What manifold are you running, and do you have any cracks, exhaust leaks which may affect spool... Check for those, what about boost leaks? Does the turbo have shaftplay yet? Is your timing on where it suppose to be and do you got anything goin on for tuning? And if all that stuff checks off good then id say I dont know, something about that turbo making it drag then, and if not then you just need to go build a 2.4 stroker and get better spool .

Yea, I found out I should have ported that a few weeks AFTER my full build/rebuild, woulda been nice to have in some of the many writes ups touching those various areas of head, timing belt, turbo upgrade etc.

Stock bottom and top end though head is rebuilt.
No cracks anywhere of any kind.
Minor boost leak at the TB butterfly, but I can still pressure test to 30psi and holds for over 30seconds.
Turbo still has no side to side play, but always had a couple millameters of in and out since arrival in the box......

Timing is dead on, and as my profile should state all these things, Im currently running a Safc II and palm pocketlogger software.
Running about 20 psi, hits this target around 5k Rpm give or take a 100.

Tune is descent for the pocketlogger setup, nothing great or exact but it works. once I get my MAf-T and 3" GM sensor in later this month or the next I'm going to get on the local Dyno with there wideband for a real test at 25-30 Psi

Probly do tubular exhaust mani and o2 housing and cams for christmass, but I get ahead of myself

Thanks for your thoughts

 

[nightspeed87]

Perhaps the higher oil pressure is pressing against the turbo bearing hard enough to slow it down a little. Thats the only thing I could come up with to make it have slow spool. But it cant be too much the oil pressures fault in your case since you dont smoke, becase I have no shaft play and i am smoking oil past the turbos exhaust seal mysteriously ???
Perhaps you can look on my thread ( in this same turbo systems section) and put some opinions from my issue as well.

 

[DoyoFCT]

These shafts effect nothing except the vibrations of the car, nothing to do with performance , all about preventative maintence for the sake of smoother idleing

i disagree with that, every car ive seen with out of phase balance shafts or balance shafts that have been damaged/causing vibrations effect the performance of the car a ton. and the result is slower spool, slower overall power, and bad response of the bov. im not saying your method doesn't work.. im just saying from my experience with cars that have out of phase shafts, this is what ive seen. and I would assume that eliminating one shaft and leaving the other completely intact could cause a similar problem. your best bet is to put a restrictor in the line to see if that helps, but if that doesnt i'd consider other things because even on a bone stock motor that turbo should hit full boost in the 4k or 4500 at the latest.

do you have a way of logging timing? i'd be curious to see what the timing curve looks like.

 

[fourreGsixty3]

You should see a maximum of 55-60psi of oil pressure to the Garrett journal bearing CHRA. The main reason high oil pressures reduce spool time is because a brass journal bearing is a floating bearing. With the correct oil pressure(55-60psi) the bearing is supose to spin in the center cartrige, and the shaft spin's inside of the bearing. This reduces the RPM of the shaft in relation to the bearing. If the oil pressures are too high then the bearing is forced into the housing, and causes it to bind up with the shaft while it is still spinning. This creates more drag due to increases shaft RPM in relation with the bearing, with more drag=lower spool time, and maximum spool RPM, and for this reason maximum achieveable boost is also reduced. This is the same if the oil pressure is too low because there isn't enough pressure to keep the bearing floating which cause it to also bind with the shaft, and this will also decrease RPM spool up time. Hear is a write-up by Paul as to making a restictor for this problem of too high of oil pressure. http://www.dsmtuners.com/forums/showthread.php?t=171317

On a side note Keith (92awddsm), and Andy( andymoraitis) are using this same set-up.

Here is some information I think would be helpful from Garrett.

Does my turbo require an oil restrictor?

Oil requirements depend on the turbo's bearing system type. Garrett has two types of bearing systems; traditional journal bearing; and ball bearing. The journal bearing system in a turbo functions very similarly to the rod or crank bearings in an engine. These bearings require enough oil pressure to keep the components separated by a hydrodynamic film. If the oil pressure is too low, the metal components will come in contact causing premature wear and ultimately failure. If the oil pressure is too high, leakage may occur from the turbocharger seals. With that as background, an oil restrictor is generally not needed for a journal-bearing turbocharger except for those applications with oil-pressure-induced seal leakage. Remember to address all other potential causes of leakage first (e.g., inadequate/improper oil drain out of the turbocharger, excessive crankcase pressure, turbocharger past its useful service life, etc.) and use a restrictor as a last resort. Garrett distributors can tell you the recommended range of acceptable oil pressures for your particular turbo. Restrictor size will always depend on how much oil pressure your engine is generating-there is no single restrictor size suited for all engines.

Ball-bearing turbochargers can benefit from the addition of an oil restrictor, as most engines deliver more pressure than a ball bearing turbo requires. The benefit is seen in improved boost response due to less windage of oil in the bearing. In addition, lower oil flow further reduces the risk of oil leakage compared to journal-bearing turbochargers. Oil pressure entering a ball-bearing turbocharger needs to be between 40 psi and 45 psi at the maximum engine operating speed. For many common passenger vehicle engines, this generally translates into a restrictor with a minimum of 0.040" diameter orifice upstream of the oil inlet on the turbocharger center section. Again, it is imperative that the restrictor be sized according to the oil pressure characteristics of the engine to which the turbo is attached. Always verify that the appropriate oil pressure is reaching the turbo. The use of an oil restrictor can (but not always) help ensure that you have the proper oil flow/pressure entering the turbocharger, as well as extract the maximum performance.

Hope this can help you out,

Dustin

 

[Ho0ked]

i disagree with that, every car ive seen with out of phase balance shafts or balance shafts that have been damaged/causing vibrations effect the performance of the car a ton. and the result is slower spool, slower overall power, and bad response of the bov. im not saying your method doesn't work.. im just saying from my experience with cars that have out of phase shafts, this is what ive seen. and I would assume that eliminating one shaft and leaving the other completely intact could cause a similar problem. your best bet is to put a restrictor in the line to see if that helps, but if that doesnt i'd consider other things because even on a bone stock motor that turbo should hit full boost in the 4k or 4500 at the latest.

do you have a way of logging timing? i'd be curious to see what the timing curve looks like.

It is physicaly impossible for the balance shafts to have any significant effect on performance. all they do is balance the vibrations in the motor to make the car idle smoothly its an asthetic thing only. The fact that you have delt with cars and the issue you mentioned are purely coincidental.

As far as the restrictor yea, I think I wil have to give that a shot and see what happens, my stock oil gauge does not peg but it goes to 75% of its travel under boost.

Thanks again for your ideas

 

[fourreGsixty3]

I would say grab an aftermarkey oil pressure guage as well cause there is no telling what pressure your actually putting out, and only a guess at a wide range of pressure possibilities, but either way it sounds like it is too high because my stock oil guage didn't go much above the middle, but not sure how accurate the stock guages are since I KNOW the stock temp. guage is not accurate at all.

 

[dsm-onster]

I removed my BS belt and felt no dfference in performance at all. My 60-1 w/ t3 stage 3 still spooled to 20+ psi by 4K. There is NO WAY in he!! an out of phase BS assembly will affect performance enough to affect spool characteristics.

Going into my wife's Camry block, I misaligned the BS assembly and the CAR vibrated, but no performance decrease.

A balanced engine and BS assemblies are two different animals.
______________________________

I don't know of any time too much oil pressure has slowed spool. I know of plenty of times where not have enough will .

Have you checked for a preturbo exhaust leak? Black, smutty exhaust manifold to head gasket?

 

[drivemusicnow]

doyo is missing the point. neither of his balance shafts is doing anything because he isn't running a belt, and doesn't have the rear in therefor 1 is sitting at rest like a 5 lb lead weight, and the other is gone.

 

[DoyoFCT]

With my balance shafts disconected but not removed

that was the original description, i based my opinion/theory on that.



after his explanation of how his shafts were removed. i understand that this is probably not the case, i would have removed them entirely but thats my opinion/experience.

These shafts effect nothing except the vibrations of the car, nothing to do with performance , all about preventative maintence for the sake of smoother idleing

the rest of the post, i was mainly arguing that this is not true, as any/every dsm i have seen with full installed out of phase balance shafts. has a huge effect in performance, dont believe me? try it. and like i said, in my description i have no idea if his method would cause the type of vibrations/problems an out of phase bs would, it was just a theory. but to state that the shafts cannot effect performance at all is false.

I removed my BS belt and felt no dfference in performance at all. My 60-1 w/ t3 stage 3 still spooled to 20+ psi by 4K. There is NO WAY in he!! an out of phase BS assembly will affect performance enough to affect spool characteristics.

again i have no idea, if removal of a bs belt.. would cause the same issues as a full installed bs system that is out of phase. no way in he!!? have you had direct experience ive driven countless cars where some idiot installed the timing belt wrong with the rear shaft out of phase and they couldnt get out of their own way. and they built boost late, and the bov would also release very late. which is where i based my theory.

Also an out of phase bs system will generally spit the bearing out at some point. but yea it doesnt effect performance at all , it can just wipe your motor out .


a camry is not a dsm, so i wouldnt compare the two in any way.

I don't know of any time too much oil pressure has slowed spool.

There's a suggested oil pressure that the centers should see at WOT, if it goes above that generally 40-60psi on a journal bearing turbo, and below 40psi for a ballbearing turbo i believe. not 100% on that. if there is excess pressure it can create a decent amount of lag surprisingly. but im sure its in combination with boost/exhaust leaks to cause a 50 trim to boost so late.

 

[dsm-onster]

No biggie Man. Just pointing out my experience.

that was the original description, i based my opinion/theory on that.

I certainly can understand that. . .

the rest of the post, i was mainly arguing that this is not true, as any/every dsm i have seen with full installed out of phase balance shafts. has a huge effect in performance, dont believe me? try it.

I accidentally did . It did FEEL like crap. But spooled fine and otherwise pulled like he!!.

have you had direct experience

Yes

Also an out of phase bs system will generally spit the bearing out at some point. but yea it doesnt effect performance at all , it can just wipe your motor out .

I must ad mit that I never drove it long enough to see if it would happen. . .

a camry is not a dsm, so i wouldnt compare the two in any way.

a balance shaft is a balance shaft. if an out of phase BS will monkey w/ the reciprocatiing assembly of a 2.0 mitsu, then why would it not to a 2.2 toyota?

But no worries. I just have seen that it won't affect spool and/or airflow. I can't see how it could destroy an engine. BUT, I've never SEEN that NOT happen, or happen.

 

[fourreGsixty3]

Good to see everyone has worked out the BS discussion in a thread about too high of oil pressure slowing spool on a turbo.

There's a suggested oil pressure that the centers should see at WOT, if it goes above that generally 40-60psi on a journal bearing turbo, and below 40psi for a ballbearing turbo i believe. not 100% on that. if there is excess pressure it can create a decent amount of lag surprisingly. but im sure its in combination with boost/exhaust leaks to cause a 50 trim to boost so late.

If you took time to read my previous post instead of going on about what is best either BS total removal, or leaving the BS in, you would have seen I already awnsered that.

 

[fwdeclipse]

What gear are you testing this in saying 5k. In 1st or 2nd gear that would be about right. Do a pull in 3rd and that is most accurate.

 

[Ho0ked]

What gear are you testing this in saying 5k. In 1st or 2nd gear that would be about right. Do a pull in 3rd and that is most accurate.

Yea this is 3rd gear

Good news update.....

Ordered today
Maf-t
Couplers
3" intake pipe
New headlights (melted drivers side of course)
New side mirrors (deer ate one)

Come Sunday I hope to be done with this stuff , wish me luck

 

[fourreGsixty3]

Any follow up on this?