Twin S257sxe turbos on a 5.3....?
 

Hey guys, trying to find out what two BW S257sxe's would make on a forged 5.3 with stock 243 heads and LJMS stage 2 turbo cam. Would it make 800hp crank? Lots of info on that turbo with 4 bangers but can't find good info as a twin V8. Thanks! T

Yes, I've made 800 crank on smaller twins, but with a more appropriate camshaft to match.

I've had a discussion with AGP using these turbo's on my next project and feel like they will be more than enough to meet your goal. Their base kit uses 54/57 (T3/ .63AR) and state up to 800whp granted that's based on a 6.2L. I was in between using the 252's or 257's (T4/.63AR) and looking to be somewhere in the 600-700whp range with a 6.0 which I believe should not be a stretch by any means. I'm hoping that if need be, an exhaust housing change to the .82 will allow for more power later down the road if I'm not happy where it ends up.

You are right though, for whatever reason these turbos seem to be uncommon?

Ok great....Thanks Joe and All!

I'd jump up to s366 units personally, you will get bored of 800 crank which is only like 640rwhp through an auto.

I agree or even the billet s362's. Those will light very fast on ur combo and still be enough for 1k

I had S251s on a 6.0 and made 740whp/810wtq at 16psi. They are much smaller than S257s, those should very easily make 1100 chp on a 5.3. I have them on my L33 and they are very responsive. I had S360s on a 6.0 and they weren't nearly as responsive. If you get them order them from AGP and get .63 or .82 open housings, the S200 turbine housings from BW are pretty crappy.

Thanks Hank! good info.....I'll check out the AGP housings.

Do any of you know if the AGP double v-band (inlet and outlet) housing works well?

Glad he pulled you out of the wood work as those are impressive results on that setup and reassures me I'm going in the right direction.

Those are small turbos in comparison:
S251 - 47lbs./min
S252sxe - 55lbs./min
S257sxe - 65lbs./min
S362sxe - 76lbs./min

What AR housings were/are you using on the 251's? Also curious on the basic rundown of the 6.0 engine if you don't mind.

The BW MatchBot looks good for these turbo's on a 5.3.
I'm not sure how to configure for the turbine side so i didn't modify that portion.
http://www.turbos.bwauto.com//afterm...6_wrsin=92044&

Hi, I tried .48 and .63 AGP housings, the .63 responded as well as the .48, within 100rpm spool time, so no reason for .48s. I moved the .63 housings to my S257s
when I got them and put the .48s on the left over S251s, now sitting on a shelf, not sure what to do with them! The engine was a LQ4 6.0 short block and LY6
heads (LS3 heads with heavier valves). LS3 intake and XER273 cam, dual springs, mostly standard everything else.

I now have a 5.3 L33 that I had a PT7675 on, that worked great, then sucked part of a coupler into the wheel and destroyed it. I put the S257s on it, thinking they
would be a lot less responsive, but they are about the same as the PT7675, and then compressors flow a bit more, and the turbines flow a lot more, so a win win win (Michael Scott wins too),
except the destroyed PT7675.

Thanks again for the good info Hank!
Do any of you know if the AGP double v-band (inlet and outlet) housing work just as well as the normal AGP T3 .82 housings? It would be easier for me to package if they work well. Thanks T

The housings will act similarly given they are a similar A/r.

just some further info, I had a set of s257sxe turbos with the .82 t3 housing. Previous owner made 1040whp on an ls3 headed 370. Through a tr6060 and zl1 diff on a 5th gen camaro.

Hey V8, cool....i'll get the double v-banded exh housings. Looks like i'm set on the S257sxe turbo's as everything has come back positive on quick spool and 1k+ HP potential. Thanks guys!

I made 1012 STD/ 972 uncorrected at 19 psi on a 383 based engine on my v band .82 on some cheap old cast 6265 turbonetics in a manual vette with c6 z diff/trans. These were basically the PTE style housings, but they are not tapped out till about 1200whp on a manual trans and lower cube engine IMHO.

Hey pete! I have projectitis, lol.....! My boat is begging for a couple of these motors and four turbo's..... :-) One motor is just about done....time for turbo's

Thank slowride!

That is getting it done. I can imagine the TQ curve would be epic compared to the 1000rwhp big turbo cars that come in so much later