AaronJ

iTrader: (12)

Right now i have an 13b with a t04r. i was considering moving up to the t04z chra for more better spool but i saw that alot of people are seeing better response and top end from the pt67. So i was curious to know does borg warner have an turbos that compete with the pt67.

I have 560 whp on e85 with 2x2200cc and 2x1000cc and im guessing ive reached the limits of my fuel system so im not looking for anything more than 560 whp

Howard Coleman

iTrader: (6)

Aaron,

you are asking the correct question re the TO4 (67 mm) series. they are 63 trim so do give up a bunch re spool.

here's what interests me in the 67 mm size.

Borg Warner S300s (363). PN 177283
there are a bunch of S3XX BWs. this turbo is similar to your TO4z.

the compressor is 7.06 sq inches V 7.002. the compressor but is quite different than the Z/R as to trim, having a smaller 63 mm inducer V the TO4r/z at 66.7.

Trim is 52 V 63.

smaller trim promotes spool.

the turbo can put out over 70 pounds per minute so it should make 550 but have great midrange. that's the theory.

also, the BW turbo has a 6.312 sq inch area turbine versus the typical TO4 at 5.89

i will be testing this turbo, along w 3 others shortly. the Precision line has the same larger trim so shouldn't spool differently than your current turbo. they (may) have more at high boost levels if you buy the billet version.

https://www.rx7club.com/single-turbo-rx-7s-23/separating-fiction-reality-couple-days-dyno-903611/

howard

ScorpionT

iTrader: (3)

The S300-63mm would also be my recommendation. It will make very similar power to your T04R (slightly more potential, lower boost) while spooling in a similar fashion. If you get the divided turbine housing, spool will be quicker.

arghx

iTrader: (3)

Do you have any literature on this? Larger trim on the compressor side also means more flow at lower pressure ratios. Trim is just an aspect ratio after all.

Zero R

iTrader: (1)

I don't have any literature but I can tell you from experience that smaller trims will spool better, but they will also require more boost usually as you implied with better flow at lower P/r's. My experience mainly comes from swapping 61mm through 67mm wheels around. That's why I tend to favor the 3574's more so than the 67mm turbo's for anything below 450whp. The 61mm compressor just comes on quicker on the same turbine wheel. Both running .70 A/r S-covers and same turbine housing.

~S~

AaronJ

iTrader: (12)

That is what i call good information and its much appreciated i was thinking about taking raising my redline to 9k (currently 8200) and make 600whp in the future but i think putting more power and tq under the curve not make the

Thank you Howard and Scorpion for the good information. I was actually looking up the s300 series but couldn't decide if the s363 suited my goals. Although 600whp with a s372 sounds tempting haha its a lil much at the time

ScorpionT

iTrader: (3)

The S363 @ 550whp would be nearly as quick as an S372 with 600whp. The S373 is much more responsive, and probably a better choice on the street. What type of fuel are you running? Any water or meth injection?

arghx

iTrader: (3)

good to hear some personal experience, I'll keep that in mind. Did you notice much of a difference in part throttle boost and torque? That's where I do find the higher trim turbos lacking a bit. I went with a T67/T04R partially because I got a good deal on it but also because I wanted over 400whp at 17psi max, and with all the porting and everything else I knew it was going to be a 5000-8000rpm type of powerband.

AaronJ

iTrader: (12)

Im on e85 and i must admit im loving the 67mm up top but i want 20 psi around 4k rpm which is why i was considering the t04z(ball bearing) CHRA but at $1000 im considering just buying a whole new turbo for my my goal. I plan on tracking the car which is why response is so important.

Dose anyone know how the borgs hold up under extended periods of boost?

ScorpionT

iTrader: (3)

What style turbine housing do you have? A ball bearing turbo wont really aid in spool, but it helps the response when on/off the throttle.

Ive seen BW turbos take a serious beating and keep ticking, pretty common.

Zero R

iTrader: (1)

Exactly where you will notice it more, it's give and take you want the higher power at lower P/r but you also don't want the lazy feel either. You can pick up power as well by going with larger A?r's if available but same issue arises with give and take. I do like the BW 363 though, but I like BB units more


~S~

Trots*88TII-AE*

iTrader: (11)

Sean just doesn't like the backplate on the BW's. Did someone say cast iron?



But seriously, the big ones weigh easily 50+ LB's

Zero R

iTrader: (1)

HA! How true, I don't like the fact it's all one piece.

~S~

Trots*88TII-AE*

iTrader: (11)

Well, like everything else it's give and take. I'm happy with the price of the BW units and I'm willing to give up versatility and weight for my drag engine. Well, soon-to-be drag engine... S475 FTW

swkiller

iTrader: (1)

i weighed my s374 a couple weeks ago its around 40lbs

swkiller

iTrader: (1)

aka the S400s in borgwarner terms

Howard Coleman

iTrader: (6)

my soon to be dynoed BW S300s 63 weighs 22.4 pounds.

Sean's GT3574 weighs 18.0

my GT4094r weighs 22.4.

the S300s weighs a bit more due to having a 90 degree bend in the compressor output tube.

hc