DrTurbo

iTrader: (3)

You mean 1.32A/R like a .66A/R.

z28mccrory

iTrader: (7)

Can you please respond to this Dr Turbo?

DrTurbo

iTrader: (3)

The 480 will outflow them due to being a MUCH larger turbine wheel, but also means much laggier. Also the ratings were factory ratings....not ours.

T4 units are much smaller to fit...that is why people go with ST and SX80. The BW480 is twice the size on the exhaust side just about. BIG difference.

jfg455

iTrader: (5)

OK, maybe I'm just dumb but won't cutting the inlet air in half just cause it to spool half as fast? shutting down the inlet doesn't change the a/r or the turbine wheel size. It still take the same amount of load to spool it but you are just causing a restriction before the housing. The flow will speed up at the restriction and then die as soon as it goes by due to the area behind the opening doubling in size. Like I said, I may just be dumb but I think a large surge pop fart black cloud is all it is going to produce. I'd like to see it work then maybe I will change my mind.

TurboAv

iTrader: (6)

When you use a twin scroll housing it's like having two .66 AR hotsides for a 1.32 AR. So when you block one side and send it through just one .66 side you increase the velocity of the gasses going into that one small AR. So it spools quick(er). But backpressure also increases because of this. That's why at a preset boost value the other side opens up and allows you to make the high rpm power.

Edit: Look up Zombie. He is using one of these "quick spool valves" and it works quite well for him.

z28mccrory

iTrader: (7)

Anyone have a picture of a T6 S400 sitting next to a T4 ST80 or SX80?

TurboAv

iTrader: (6)

+1

How about some dimensions also?

jfg455

iTrader: (5)

So the housing is split all the way to the vanes yes? If so then that makes more sense. Most of the "split" housings I've seen only go in about 1/2 way and then join into one big opening so to speak. I'll check it out. thanks.

black98ws6ta

iTrader: (77)

A twin scroll housing is divided from the flange to the turbine wheel.

TurboAv

iTrader: (6)

I would think you would even see some benefit even if it wasn't split to the vanes. Obviously split to the vanes would be better, but you would still be accelorating the exhaust gas either way. Like blocking off the spray coming out of a hose to make it spray harder. You would be hitting the blading with more force at the expense of backpressure. Which is why the valve opens up once you are spooled.

kbracing96

iTrader: (25)

You can see in this pic of how far the divided scroll goes.

mightyquickz28

iTrader: (8)

Holy cow!! Man! That thing is a farkin' GIANT! Lol.. Thanks for posting the pics of them side by side. I *barely* have enough room for my single TC76 (Thanks for it too Dr. Turbo!) and there's no way in hell that giant thing would fit in my setup (stock radiator orientation).

_916ls1z28_

does any have the dimensions of the s475 t6 and the s475 t4 with 1.10 a/r . i need to know if it will fit battery mounted.thanks dr.turbo

want1ls1

i have the s476 and it is a good little turbo. AND FOR THE PRICE YOU CANT BEAT IT

aussie-revhead

Hi guys, this is my first post here so hi to all

I am looking for a turbo for my street/drag 355ci v8, what size BW is the best balance of size and power ? The s400 sounds like it will be too laggy for a road car without massive stall to compensate , so what would you guys recommend ? Im only looking for 600rwhp but if it makes more then I wont complain . Also, my budget is a bit tight so no ball bearing garretts for me , thats why Im looking at these .

Any help would be great.

TurboAv

iTrader: (6)

With that goal a TC/MC 76 or 78 by Turbonetics would be a great turbo, IMO. Quick spool and will make more than your goal. Email DrTurbo with your whole setup and they will steer you correctly.

aussie-revhead

Thank you.

That quick spool valve is a nice setup , where are they available from ?

mightyquickz28

iTrader: (8)

We'd really need to know more about your car, your engine and your driving style to say with any clarity.

• Weight of the car as you envision, once it's complete
• Compression ratio
• All forged bottom end or mostly stock?
• Cam
• Heads (factory or aftermarket?)
• Front mount Turbo or Rearmount?
• differential gears
• Transmission
• If automatic, TC stall
• Hotside type(log or headers)
• Driving style(Mostly strip, mostly street, highway, heavy traffic, etc)

You, like most of us, mention budget. How much can you honestly devote to this? Whatever you think it will be, add 50% to that.

Hope you build it! These cars are more fun than anyone can believe!

aussie-revhead

Thanks but I better start a new thread in the non-LS section as its not an LS motor , or a motor you have available in USA though Im sure alot of the same stuff applies across the board. It will look something like this pic, it belongs to a fellow aussie named C4PRCE



Edit: Is there a better section to post details of my non-LS powered vehicle ? Or is this the most relevant section since its about s400's ?

This is the type of vehicle I have:

http://www.vnss.com.au/category/exterior/

posenheimer

How big of an effect will choosing a t4 for a Borg warner S400 vs the standard T6? And how much more power does the BW Race housing add??