Ball bearing PTE 50 trim

[b4christ15]

blcknspo0ln:

Awesome comparison info there. Looks like the BB5031 has my vote when I upgrade.

 

[blcknspo0ln]

thanks guys..

P.S. I trapped 110mph with a shitty 2.5 60ft'

 

[tbTalonES94]

Did your turbo come originally setup of an internal gate and you removed the flapper when going to an O2-mounted gate?

As blackGSX2g mentions, an O2-mounted external is no guarantee against creep as you still have the same limitations of a sharp turn into the bypass passage and the stock internal WG hole which is nowhere near the 38mm passage your Tial is equipped with

Sorry for not responding right away...didn't see it.

I got the turbo originally without the flapper. In otherwords i bought it set-up for an external gate off of the o2 housing. I did not do any porting, hoping that a good Tial gate would alliviate the usual problems. Well my Hallman just wasn't doing it and i opted to get a Greddy Profec spec-S. Boost shoots up faster then before (3600 full spool) and holds solid most of the time to red-line. I'll get creep everynow and then but its not bad and I have plenty of fuel if it happens.

I may either re-make my o2 housing to dump, or take the turbo off and port it. It would be easier for me to re-make the o2 housing because i have no porting tools.

Just to let you guys in on some performance. I ran a 12.5@111 with no tuning,93 octane, 12* timing, 3 knock retard (dsmlink), ~18psi with a 1.7 60ft. I will be going back here soon now that I got a much better tune and steady boost. Hopefully getting in the high 11's on pump.

-Trevor

 

[Shane2GSX]

Can someone help me out here, I'm going to be purchasing one of these very soon along with the rest of my setup, and I'm not sure what the difference is between these two. The one from importevolution says it's an "RE" the one from slowboy, "RLE". Does anyone know the difference? Are they the same?

http://www.importevolution.com/product_info.php?cPath=111_113&products_id=2929

http://www.slowboyracing.com/shop.php?sid=&cat=4080

 

[DSM90AWD]

The "E" or "LE" portion of Precisions naming convention refers to the compressor cover.
E= TO4E
LS = TO4S

Not sure what "LE" means, but find no mention of it on other PTE vendors sites other than SBR so may just be their naming convention (or a typpo)

 

[LRS95TSI]

people continously tell me from my area that the bb 50 trim surges too bad and is not efficient...also they say that the cut divider ruins turbine efficiency...just curious as to what the real synopsis is...i like the bb 50 trim but for that price, it's almost better to go with a bigger bb turbo and keep the boost a little down...

 

[90blacktsiawd]

Do any of your friends have personal experience with these turbos?

I can't say i've had even a hint of surge out of mine in the apst 6 months that i've owned it. I also can't see how it would be any less efficient than a regular 50 trim. They are correct about the fact that cutting the divider will hurt the efficiency of the turbo though. It creates turbulence when the wastegate opens in the exhaust stream. It does however help an internal wastegate maintain control over the boost.

 

[tbTalonES94]

I never had a surge problem. 22psi by ~3600 no surging.

Ran a best of 12.0@114 with a 1.6 60ft and 15* timing. 93 pump gas. 11.4 a/f.

This is one awesome turbo...let me tell you. You won't go wrong getting one.

-Trevor

 

[Strm Trpr]

First you say this:

I can't see how it would be any less efficient than a regular 50 trim.

Then you say this:

They are correct about the fact that cutting the divider will hurt the efficiency of the turbo though. It creates turbulence when the wastegate opens in the exhaust stream.

I understand how when the wastegate opens the turbulence hurts the exhaust flow from the turbine, but how bad does it actually hurt efficiency?

Is this inefficiency measureable in e.t., trap speed, dyno numbers?

Does it hurt spool time of the turbo?
I mean once you fully spooled and rippin it up at say a set boost of 22psi, the gate opens, then what?
What does it do at that point?

 

[LRS95TSI]

i would like to know the same, because i would never push the turbo past 22psi...hopefully on a good tune that would net me 350-375 whp o a good tune. just curious, this is a good hread since ppl who actually own the turbo are chiming in, it helps with real hands on information....KEEP IT UP!

 

[Strm Trpr]

Also, most larger turbos don't like to be run at low boost.
So if your friends were running that low of boost on that 50, then perhaps that could be the reason for their problems.
People say a 50 shouldn't be run under 20psi anyway, and really come alive after 25psi.
Turbos have surge limits, and if someone runs a pressure ratio to the left of the comp map, they are in the surge area of the turbo.... not good.

 

[LRS95TSI]

correct, but it would be cool for some1 to be able to define at what boost the bb 50 trim is worth it...either you push a evo3 to 25-27 psi, or you push a 50 trim to 19-22...i'd rather push the 50...just wanting to get more feedback...what are some other bb alternatives that have similar capabilities, maybe a little bigger?

 

[DSM90AWD]

The inefficiency of the cut turbine dividor is not specific to the BB version, all Mitsu bolt-on PTEs have this "bandaid" option to remedy a poorly designed wastegate outlet cast into their housings.

I dont' think you can quantify efficiency loss, though I've found many people that have gone this route either having difficulty reselling the turbo due to this "hack" and/or wanting to but not able to get an O2-mounted external after still experiencing boost issues (you'd have to get a manifold mounted gate if this mod was done).

I'm flowing 49lbs-min on my conventional bearinged 50-trim @24psi on 93octane. . Dont' know how much more it will go past that

 

[tbTalonES94]

I was flowing close to 48-49lbs at 22-23psi on my BB 50-trim according to DSMlink. That was on 93 octane and on a nice cool night.

I've also ridden/helped tune in a standard bearing 50-trim 2g set at 18psi and it was still running really hard. Every car is different, but from what I have experienced the 50-trim is a GREAT pump gas turbo all around if you are looking for 350-400 reliable horsepower. Yes it can be pushed past that and has been done many times, but i'm saying with pump gas, good tune and not sky high boost levels 350-400hp is great.

 

[90blacktsiawd]

When i said i can't see how it would be less efficient that's ignoring the cut divider. If both version were cut or uncut i cannot see hwo the efficiency would change due to different bearings in the center section. Still the same wheels in the same housings.

With a cut divider you add turbulence to the exhaust when the wastegate opens and mixs its gas with the main exhaust passage making it more difficult for the exhaust to exit smoothly and unobstructed. Which is where the idea of it taking away efficiency comes from. I have no raw data to back this up. It comes form what i've learned and people i've talked with over the years.

LRS95TSI why would you never turn it up past 22 psi? That makes no sense. Unless it's purely for your motors sake. The turbos still got more in it to give at higher boost levels. I could understand saying you wouldn't take a 14b higher than that but a turbo of this size loves to run higher boost levels. I myself run 22psi on a daily basis on pump gas. The only reason i don't go higher is because i don't feel the need to blow my battered bottom end before i have another waiting to go in my daily driver. For your reference, i put down my dyno numbers @ 22psi. So your definately capable of 350-375 at around 22psi.

 

[tbTalonES94]

When it comes to strictly airflow, the bearings aren't going to effect the efficiency of the turbo i'm pretty sure. I'm no turbo guru but both turbos have the same compressor wheel, turbine wheel, housings....they are going to flow the same regardless of the bearing section. That's of course not taking into concideration of the cut-housing...which in my opinion with the added tubulence would just slightly hinder turbine performance.

 

[CanadianTSi]

My housing is cut on my Internally gated 50 trim. Doesn't seem to be hurting the performance all that much.

 

[tsiawd1995]

My housing is cut on my Internally gated 50 trim. Doesn't seem to be hurting the performance all that much.

So is mine 11.3@127

 

[IPT]

I never had a surge problem. 22psi by ~3600 no surging.

22psi by 3600rpms....

What gear was that in? My old journal bearing 50 trim would spool around 3400-3500.

Please check your setup if you still have that turbo.

 

[Strm Trpr]

Dude, you have a Ported and Polished head and Web Cams of course you'd spool it sooner....
Maybe that's now, and not then when you ran your old journal bearing 50.

 

[CanadianTSi]

So is mine 11.3@127

I hope to see times like that Next season with some Race gas and Real Boost

Also My journal bearing 50 trim would hit full spool at 3800 before the cams/IM.

The place where dual BB shines is transient boost responce, not so much on the Actual Spool-up.

 

[daren_p]

22psi by 3600rpms....

What gear was that in? My old journal bearing 50 trim would spool around 3400-3500.

Please check your setup if you still have that turbo.

What gear would you spool a journal bearing 50 trim at 3400-3500, what boost and what mods? That seems to low for a std bearing turbo of that size. My evoIII hits 20 psi @ 3400 rpms in 3rd & is now around 3500 after the cams. Most guys aren't seeing your times on the BB version so not sure how your doing it with a non BB? Is this from a log or going by the gauges?

 

[LRS95TSI]

LRS95TSI why would you never turn it up past 22 psi? That makes no sense. Unless it's purely for your motors sake. The turbos still got more in it to give at higher boost levels. I could understand saying you wouldn't take a 14b higher than that but a turbo of this size loves to run higher boost levels. I myself run 22psi on a daily basis on pump gas. The only reason i don't go higher is because i don't feel the need to blow my battered bottom end before i have another waiting to go in my daily driver. For your reference, i put down my dyno numbers @ 22psi. So your definately capable of 350-375 at around 22psi.

22 psi would net me my goal of hp....if i wanted to go higher i would add a new 4 layer hg and arp hardware...and i'm trying to nurture my 7 bolt with a decent to good tune, to give me some cushion thats all...

QUESTIONS:
1. i'm guessing cams slow the spool up on ## turbo correct? fp1/fp2 setup
2. what are similar bb turbos of a 50 trim? gt3071?

 

[daren_p]

22 psi would net me my goal of hp....if i wanted to go higher i would add a new 4 layer hg and arp hardware...and i'm trying to nurture my 7 bolt with a decent to good tune, to give me some cushion thats all...

QUESTIONS:
1. i'm guessing cams slow the spool up on ## turbo correct? fp1/fp2 setup
2. what are similar bb turbos of a 50 trim? gt3071?

Correct cams always add a couple hundred rpms to spool up, depending how "agressive" the cams are will relate to how much longer it takes to spool. My 1x's were around 100 rpms slower, think the reg 2's are a couple hundred rpms.

You should probably change your question about BB turbos that are 50 trim if you are just looking for a similar sized turbo. Trim has nothing to do with size or the airflow the turbo is able to produce. Trim is simpley a ratio of the comp wheel inducer vs exducer size. So you can have say a comp wheel that flows 25 lb/min thats a 50 trim which you can also have a turbo that flows 75 lb/min that also works out to a 50 trim. Think the small 16g works out to be ~ 60 trim, which obviously is totall different that the typical hybred "60 trim bolt ons" that they talk about in the dsm community. This is why you shouldn't go by trim size when refering to a turbo size as it really tells you nothing as far as the airflow capabilites of the turbo. Better to ask for comparable lb/min compressors.

 

[Strm Trpr]

I stand corrected.
I had no idea, I figured cams would help spool up, but apparently they help breath up top.
Ah, I got it....