After all this discussion on custom twin turbos , I am seriously thinking of going that route . I am now trying to figure out what size would be good for my application , I've read about people using different sized compressors and turbine a/r's , I guess it will all depend on their overall configurations.
Based on my new setup (basically its a semi pp with the pro j intake) can anyone suggest a proper size for the turbos , I want her to be a street / strip monster with way too much power , I am looking for good response (hence the twin bb turbos) and BIG power , I am also setup (W.I) to run 20+ psi boost!!

 

Twin GT35R's with 0.82 rear AR housings is what I am using. This will be ideal for you

Great set up and will support massive power, with low exahust to intake pressure ratio's

 

My engine is designed to work form 6000rpm to 11000rpm, do you want power levels of 1000+++bhp then this combo is for you..... If you want lower power then some smaller sized turbo's you need to find

 

can u post pics ur setup man

sounds wicked

pleaseee

mike

 

pix!

 

Holy F@#K , 1000bhp+ !!!! , dont know man , I may get in too much trouble with that much !!!
So you're saying that you expect them to come on from 6000 rpm ?, I think I'll ant the power band a little lower , I think 0.63 a/r exh. housings will be a good compramise , what ya think. ??

 

Tease

 

Rice Racing,
I know you are running insane xhaust ports. What are your intakes. Would you have any power numbers so I can get more accurate with my flow numbers. The flow numbers below are based on the scoot car but I have very scittish data on that.


Marcel
I was looking at the GT3071s, pretty new turbo iwth fast spool. Turbine wheel is 60, 84 trim and your choice of housinf, which is 63, 82 and 1.06. No idea which one is best for your set-up. I did some analysis on the turbine housings and i tlook slike at 1.5 pr the housings support 15, 18.5 and 23 lbs/min and a max of 21, 23 and 27 lbs/min. As a reference the GT35 support 21 and 24 with .82 and 1.06 ar and a max of 26 and 29 lbs/min. So we know the 35r chokes at higher boost, so our engines push more exhaust gases then the GT35r is happy with. No clue how much but with 2 30s you can support a lot more flow.

As for the compressor, 2 30s will easily support a semi pp flow needs up tp 30 psi of boost. My calculation tell me that you would flow 80lbs at 8000 rpm and 30 psi and 92 at 10k. No problem for the two turbos.

CW

 

Soon soon

 

How about a pair of 35/40's using 0.63 a/r turbine housings ??

 

Howw do these specs look for a twin setup ??

DUAL GT STEEL BALL BEARING CENTER SECTION

TURBINE SPECS: T25

.86 A/R HOUSING

76 TRIM GT SERIES WHEEL

COMPRESSOR SPECS: TO4S HOUSING

.70 A/R HOUSING

48 TRIM GT SERIES WHEEL

COMPRESSOR FLOW: 44 LBS/MIN

4 INCH INLET


Or how about the T3/60-1 (X2) in the link ? , http://store.yahoo.com/cheapturbo/gart3w63artu.html

 

Hey Rice, I think you should use twin GT42rs, 2400bhp. Spool might be a little slow but peak hp@ 20,000rpms will work. Hope your carbon carbon clutch works! Ralph

 

Marcel,
As I said before the T25 set-up will limit you oncew you are looking for more power. Go with a T3 and you have room to expand.

Picking the right compressor is relately easy. I wonder if we can some help on the turbine selection. It seems like semi BP have no problem spooling 1.05 A/R on GT40s. What will that equate to in a gt30? Hard to find Turbine flow maps.

CW

 

Buy my GT30 with a .86ar exhaust, then get one more

 

Well the guy who made the down payment on my single last December recently contacted me and said that he has the balance of money for me , so It seems like I will be selling it after all . I also noticed that the price of the GT42 has since gone up from $1750 to $2400 (on ATP's site) , which is almost the same as a pair of smaller GT-R turbos . So i guess the cost factor has been negated , so now I am leaning more and more toward a pair of custom twins ! , how do you guys think a pair of GT35R 's with 0.63 a/r turbines will suit the needs of my new semi pp motor ?? , I am looking for the air flow to make big power , but the response of a smaller turbo since my car is primarily a street machine.