Fastest Spool 750 HP Turbo.
My setup is a Stock 5.3L L33 with boost accommodating strength mods.
I just sold a Borg Warner s475 T6 because it was too laggy for me, and now I am looking for something that spools much quicker but will make less power overall.
I have been reading around the forums trying to find dyno sheets and answers to this, but most of these turbo ls setups are for drag racing, and include automatic transmission spool vs traction information that I do not care about.
I am looking for the earliest rpm tire spinning (SINGLE) turbo, that is $1700 or under.
My main choice right now is the PT6766 1.32A/r T4 Divided Ball Bearing, but I am still very open to other ideas and options.
Here is what I did this year on the S475 T6
Last edited by stukellymotorsports; Jan 3, 2016 at 11:28 AM.
I'd go with the 11 blade S366 with the .88 T4 housing if you wanted instant spool. It will meet your goals and light off quick. Sturdier unit than the precision based turbos IMO and costs much less.
http://www.smedingdiesel.com/product-p/bws366.htm
If this is your hotside/coldside on a 5.3 liter thats alot of your problem IMO.
Last edited by Forcefed86; Jan 3, 2016 at 11:28 AM.
and Yes i had read alot of not so good reviews across all motor platforms of precision failures which is also why I am still open to other ideas. The borg warner does seem like a very stout (heavy) unit and are probrably cheaper to rebuild.
What made you choose the .88 housing on that BW vs the .91 Divided? To my knowledge the divided housings spool faster but may flow slightly less.
When your on and off the throttle constantly in a drift car I'd want the 360* thrust bearing as well.
Also FWIW for a twin scroll setup to work properly you need to divide the exhaust pulses from bank to bank. Because of the firing order on a typical V8. There is no simple way to do this easily. There is very little gain in using a twin scroll VS an open scroll housing IMO, but every little bit helps. Was also easier to fabricate than making/buying a good merge and keeps the exh gas at a more constant velocity.
Last edited by Forcefed86; Jan 3, 2016 at 11:45 AM.
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Did you get a chance to test same motor/turbo with new hot pipes?
The Best V8 Stories One Small Block at Time
69mm SXE
That said, the 6766 would probably work too....just not sure how much faith you'd put in it being reliable.
A T6 and with 2.5" pipes was always going to be laggy !
The ones with issues usually let everyone known about it. not saying people havent had failures, but its not like your guaranteed to have the turbo come apart.
That being said the bw will probably make a little more power, wont run out of breath quite as fast as the precision, and its much cheaper
The precision is easier to package, should make very close to the same power as the borg, and spool faster.
- Borg Warner 4" Inlet 2.5" outlet compressor housing with port shroud map width enhancement, pre tapped for speed sensor and pressure port. (parts not included and will need to drill through)
- 66.11mm inducer 91.44mm exducer FMW Forged Milled Wheel (Billet)
Quoting peak max flow means nothing, as you will never even get near that section of the map in single configuration with the v8
The 69 is skewed farther to the right at the lower pressure ratios he will use, hence better suited for his application. And for an honest 750whp
The 69 will spool stupid as is so I don't see the argument.
Had twin old cast 66s and swapped to the new 69s and on the dyno overlay there is zero difference in spool between the two, just alot more power
Quoting peak max flow means nothing, as you will never even get near that section of the map in single configuration with the v8
The 69 is skewed farther to the right at the lower pressure ratios he will use, hence better suited for his application. And for an honest 750whp
The 69 will spool stupid as is so I don't see the argument.
Had twin old cast 66s and swapped to the new 69s and on the dyno overlay there is zero difference in spool between the two, just alot more power
I don’t claim to know how quickly either will “spool”. Though without a side by side comparison, I don’t’ see how anyone can claim the SXE spools faster or slower than the 11-blade 66 (or which makes more power). I don’t know of anyone running an 11-blade unit, or of a compressor map for one? They use the same exh. wheel and housing so the difference is all in the comp wheel, no? I doubt the 2 would spool “the same”. I know the OldGold guy had the billet 66 6-blade .91 S366 on his “cam only SBE” 5.3 and made 650whp at 14lbs and 13* timing. He later ran 20 on the street claiming it never fell off power wise. No track numbers though so who knows…
Last edited by Forcefed86; Jan 4, 2016 at 09:53 AM.
And splitting hairs on spool, either of the Borg 300s with the 73/80 no matter the compressor are going to be a light switch
Here is dyno overlay.... 80e car locked... One with the standard sx3 66, 73/80-.88
And the other with nothing else changed the sxe 69 73/80-.88
Reds are engine rpm. Blue are trans input shaft speed
Can see the response is identical. But the converter let's go on the 69s because it can't couple the extra TQ

He said best, not cheapest










