Throwing turbo ideas around

[blue68383]

Ive been researching turbos lately and Ive been thinking. What do you guys think about running a turbo that makes good power in the 3400-3800 range with dual fuelers and detorquing the tune to only make about 1100-1200 tq max and make close to 1000 tq at 3600 to get a little over 700hp to help the engine last until I can save for a mild build? I was thinking about maybe a s400sx3 which is 72mm ind comp and 74mm exd turbine with 1.1 ar t4 housing. Would this be a good turbo for what I want? I am trying to wait till I get my tax return to buy the turbo and install kit but I might pull the trigger soon. I would get the turbo now and within the next year get socal 60 overs and stroked cp3 or dual fuelers.
thanks
Nate

 

[othrgrl]

That's the same turbo we had on Winston's truck when it dynoed 760hp on fuel (with stage 2 heads being the only performancing enhancing engine mod), so the turbo is definately capable of making over 700hp. Whether you'll be able to write a tune that meets your goals for your RPM ranges is hard to tell.

 

[blue68383]

Did it make good power in the 3400-3800 rpm range? I believe I could get it with a bigger turbine wheel to help move the curve up higher in the rpm range if I need to correct? Also how does it spool and how drivable is it on the street?
Thanks

 

[othrgrl]

It is very drivable on the street - we towed my truck on a trailer to Florida and back with it (17K gross). It's more laggy than it would be with a tighter AR housing, but not by much. The 87mm turbine (the one you listed is more commonly referred to by it's inducer, which is 83mm) would make it alot less streetable, especially if you don't have the fuel to get it lit. I would have to have Winston scan and send me his dyno graph so that I could see where it made most of it's power and how much torque he was making.

 

[blue68383]

Hows your s475?

 

[othrgrl]

With the .9 and 1.0 housings I've tested on the 83mm turbine it does very. The numbers in my sig are on fuel only with the .9 housing on some rough tuning. It did very well sled pulling as well. I have towed a car to Mississippi and an SUV back, and towed another Duramax a couple hours all with no problems. At 1600 RPM on the 1.0 housing it will start to build boost before hitting 1000* EGTs. Overall I'm very happy with it for daily driving and all around performance.

 

[blue68383]

What does your torque curve look like with the s475?

 

[othrgrl]

This was with the .9 housing on an 83mm turbine on Dave Dunbar's dyno at the OBX Pro Diesel Challenge:

He rolled into it at about 2200 RPM, by 2500 RPM it was over 750 ft lbs, by 2700 RPM it was over 1000, by 2950 RPM it was over 1250, and it peaked at 1324 @ 3100 RPM. HP went over 750 at about 3000 RPM and was over 800 and almost flat from 3200 RPM until he let off at 3750, with a peak of 821. It was 2 days after I got the built motor running so he didn't want to run it too high in the RPM.