turbo sizing
 

What do you guys think of this turbo,what sort of power do you think it would make on a 13b bridge.

Compressor,turbine maps attached.

http://img298.imageshack.us/my.php?i...an000111ha.png

http://img298.imageshack.us/my.php?i...an000123tg.png

assuming optimized everything including tuning...

497 at 14.5 psi
527 at 22 psi

howard coleman

would you say that is fly or wheel. trying to learn

Thanks Howard,how did you arrive at those figures,am novice when it comes to turbo sizing,am trying to learn also!!!!!!!!!!!!

Gd question sdminus! Is that fly or wheels.

Looking to make 550rwhp,was told this turbo would produce that?

sorry.... those are rwhp #s.

as far as how i derive them...

i use two methods that both end up at the same approx spot.

lbs/minute times 10 divided by 1.3 results in rear wheel rotary hp

lbs/minute times 14.471 equals CFM divided by 1.92.

these formulas have worked well for me over the years. the hp # assumes everything is optimised.

howard coleman

Wow...only a 30 whp gain when increasing boost from 14.5 psi to 22 psi?

Cool!!!! How would this turbo compare to something like a t51 spl for example

Scott

the links dont work for me..

Just tried them, they work fine

max flow off the compressor map is approx 73.
max flow at 1 bar is 68.

5 lbs/min times 10/1.3 is 38 rw rotary hp.

howard coleman

I dont understand. If you say that 5lbs/min = 38hp, then 68lbs/min = 516. And this is on 1 bar.

At 1 bar turbo flows 68lbs/min which = 497 rwhp.
Maximum flow of turbo according to compressor map is 73lbs/min.

73-68 = 5lbs/min which = extra 38 rwhp at maximum flow

497 + 38 = 535 rwhp

Gary

You dont understand what im saying.

Where did you get the equation (xlbs/min*10)/1.3=rotary hp?

because if I go by that equation 68lbs/min is not 497 its 523.

Man .... now im really confused !!!!!!!

since i started all the confusion i should straighten it out. i do apologise.

here's how i see it.

2 methods.

given:

68 lbs per minute at one bar or 2.0 pressure ratio.

68 times 10 divided by 1.3 equals 523 rw rotary hp

68 times 14.471 to get cfm (984) divided by 1.92 equals 512 rw rotary hp

at max flow 73 pounds per minute

73X10/1.3 equals 561

73X 14.471 equals 1056 CFM divided by 1.92 equals 550

howard coleman

Ok what if this turbo was on a 20b?

Thats what I came up with. But the first thing you posted was that

assuming optimized everything including tuning...

497 at 14.5 psi.

(68lb/minx10)/1.3=523 not 497


edit* Ok I think I know what you are trying to say. You are saying that it flows 68lbs/min at 1 bar and max flow is reached at 22 psi ?

T-von,

I think that regardless if its (turbine) max hp is XXX its max would still be XXX regardless of the motor it was put on, becasue it can only flow X lbs/min of air.

I could be wrong though as I am certainly not a turbo guru.

kenn

I understand that but the reason I brought up the 20b is because it has 50% more displacment than the 13b. Therefore wouldn't this same turbo make the same amounts of hp but at a lower boost level? I just wanted to see how much boost it would take for a 20B to make the same 561 (max flow) hp.

yes i think you rite about that. aswell as chosing a larger turbine wheel, the compressor would aproach max flow at lower boost level or lower rpm on a 20b. so this is were you can use the same compressor but with a different trim that has better efficiency at lower boost levels to develop the same power more effectively.
I think the trim can play a big role on boost efficiency.

All you have to do is look at the comp. map. The turbo, no matter wat engine its on, will not change characteristics.