Hey guys, I've been doing research in preparation to start my turbo build and I think I've found the right turbo for me. My goals are 350-450 whp when all is said and done and this turbo seems to be an excellent choice efficiency and output wise. I just wanted to get some more input from people with actual real world experience with this turbo

 

8th gen SI
5857 jb .82 ar vband T3 housing

Full boost around 4700 rpms (12 psi), boost starts around ~2k
457 WHP / 322 ft lbs tq

= One satisfied customer.

 

damn, those are some really nice numbers! Care to give any more info on your build? Also what tuning program are you using?

 

I ran a cast wheel 5857 with a .63 hotside and a .60 cold side. I made 400whp on pump 93 running 16lbs of boost. I switched to ethanol and made around 450whp at the same boost level. The engine was a 81.5mm 9.6:1 compression b18c1. I highly recommend this turbo for your horsepower goal. It will be super responsive and have an awesome powerband on the street.

 

thanks man. my build is pretty simple.

~ stock k20z3
~ 3" TBE
~ 1000 CC injcetors / walbro fuel pump / crushed fuel pressure regulator (increased fuel pressure)
~ 5857 ported S cover .82 ar
~ tial q 50 mm bov
~ precision 46 mm wg
~ 4" intake
~ hondata 4bar
~ heat range 9 plugs

All tuned on Hondata flashpro.

 

awesome. I know this turbo is not a popular one, but there has to be more people running it. Post away people!

 

yeah, precision gets a bad rap. it's not unearned, though, they're having a lot of quality issues lately. this is my second one (redid my oil return), if it craps out, i'll never buy another precision.

as for the capabilities of this turbo, it's awesome. as fast or faster spool than a gt3076r, makes more power. sounds saweeet when spooling, if you're into that

 

hopefully someone with this snail on an ls motor can answer this:
about what rpm would i see full boost? (considering a stock or relatively stock ls with 3'' exhaust)

 

bumpski

 

You know meta you the one that told about the 5857 on prevois thread I started. I'm saving up to get one but I was thikin its crazy how everyone has nothin but good things to say about the gt3076 (and a lot people have put down good numbers) and 5857 is soppsoe to be simalar. But it seems like nobodys running the 5857(at least in forum world). I know precions has been having there problems lately but everyones buyin still 6262. I don't know I think it has to do with the "big turbo trend" and cats puttin a gt35 on stock singles on 10 psi "pullin hard" lol. Sorry for my rant. I just thought it was odd there wasn't more people running this bad boy.

 

Well, this is what I've gone through with mine.



Billet, ceramic ball bearing, .63AR vband hotside.

Made 402whp and 286wtq on a Dseries at 27psi on E85. This was on a street tune by the way.

Then it did this.





After talking with some people on here it was discovered that it was because I was using the Precision restrictor only and had no other restrictor. So, I cleaned everything out, and did this to my feed line.





Installed a .030 inline restrictor, no issues since!

Will be going back to the dyno once I get the money and seeing what it does around 35psi.

All in all I really like the turbo. The spool characteristics are very good, spools quick even on my Dseries. The only downside is that they're fragile. It's easy to ruin the seals if you're not really careful with your oil pressure going in or have a bad return. The addition of a .030 restrictor actually has HALVED my oil pressure at the turbo, so take that for what it's worth when you set up your oil feed.

 

But that can be said for any other GT-R series turbocharger as well. Though Garretts have a small restrictor, the need of a .030" restrictor is still required. the oil pressure at the turbo itself will go down to a steady 22psi.

 

Interesting, I know restrictors are a more required piece on BB turbos but what exactly is the "cut off" pressure wise when needing to use one on a journal bearing turbo?

 

User Killer_B's car was pretty impressive with the billet 58.

Piston/Rod GSR, Precision 58/62, ek hatch
Car made 604whp w/o nitrous and 630whp w/nitrous and lower boost
10.5 @ 145 was the best time before he parted it out.

Tuned by Fred @ HPC.

 

Anything over 80psi of oil pressure has a recommendation of a .060" or .065" restrictor on a Journal bearing turbocharger from Precision, Turbonetics and Garrett

 

noobish question:

is an underhood oil pressure gauge as useful as an in cabin one? figured you'd want to be able to see the oil pressure under load

 

On a cold motor most hondas make to much oil pressure for the turbo so the oil pressure gauge under the hood for the turbo pressure is just fine, adjust it on cold oil and when motor is hot at higher rpm you will get the same pressure

 

Seems to me like Precision is causing a lot of their own problems by telling people not to run a restrictor since the common complaint I see is "blown seals." Then the addition of an appropriate restrictor tends to fix things right up. My Precision turbos have been great, but the bigger one (6265) definitely needed a restrictor to not smoke under idle conditions with oil at full temp like when cooling down the turbo bearing before shutdown..

 

ah got ya, would think once the motor warmed up oil pressure would go up due to viscosity. thanks turbo-ls, you've answered like every one of my crappy questions here and in the ls turbo thread. lol

 

5857 is a great street turbo. I highly recommend it for anyone that likes a street friendly powerband.

Take special heed to the warnings about oil restrictors and make sure your oil return is run properly and you won't have a problem.

 

No, the oil pressure goes down because as the oil heats up it thins out. As for deciding to put the oil pressure under the hood, it's just to "know it's there." I can monitor it on the dyno and during idle. It's also mechanical, so running a line into the cabin wasn't something I wanted to do from that location.

Works great. I like under the hood gauges.

 

ah yeah, i was thinking thinner -> flow better -> higher pressure but it does make sense that it would take more pressure to squeeze something thicker through a small hole rather than something thinner. thanks for the info guys.

anyone have actual comparisons on full spool rpm between journal and ball bearing versions of this turbo?

 

We've had a couple of build errors from precision. Also some very "tight" jounral bearing turbo's some where the impellors will scrub the housing with very little side load. Sadly they don't sell spares so we've had to make our own parts up from Garretts and get them machined.
They are good performing turbo's but there name is "ironic" at times.

I think the main difference is reliability. I cannot see how the ball bearing will spool much better apart from less inertia. Ones you have oil pressure there little/no extra drag from a journal over a ball bearing IMO.

 

Lets bring this thread back up. Has anyone had any new numbers? Just bought one and wanting to see what i should expect!

 

I am using one on my current build. I will post results when it is finished.