Following on from the discussion of the last few days , this is how I would see the progression for hp using the base Greddy kit .


240- 260whp - stock greddy turbo with the usual recommended upgrades

280-300 whp - Upgrade the compressor to BNR T04e 50 trim or equivalent . Do the wastegate mod or upgrade the actuator .No other major changes required.

330-350 whp - Upgrade the compressor to BNR 60-1 , upgrade the suction piping to 21/2" min the compression piping to the I/C to 21/4" min , upgrade the I/C . Modify the turbo exit for better flow . Fit 3" exhaust . Upgrade fuel pump , injectors , ignition . Do the wastegate mod or upgrade the actuator. Then pray it all hangs together .

 

Double post FTW

 

i think he just wanted to get to the next page.

 

you fail for not using the 50 posts per page maximum. LOL

 

it is our nature to mess with stuff. That is how some others make a living.
The scariest words that get in my mind are " I know what i am doing and I can make this better".
If i ever say that out loud my wife has been asked to hit me in the head with whatever is closest.
I remain curious about things, but I now draw the line in making things better. I have learned SOMETHING.
OD

 

Some things I make better and some worse.

 

what are those measurements

 

2-1/2" turbo inlet
2-1/4" turbo outlet/intercooler inlet

I agree, bigger is better. lol... its just really really hard to do with similar pipe routing as the greddy kit.

 

have to admit i saw that happen and thought F it . Looks good on the top of the page ..... heh

 

65mm and 60mm using the correct terminology for the rest of the world ...

 

I found this helpful

Your actual results may vary (ie when you add an IC) so just use my numbers as sort of a bench mark to compare different piping sizes. One thing you guys will notice is that none of the velocites goes above 304 MPH or 0.4 mach. According to Corky Bell, Maximum Boost pg 61, 304 MPH or 0.4 mach is the point at which airflow meets increased resistance (drag) and flow losses are experienced.

Anyways here are the numbers I came up with. The velocities are in miles per hour and mach, and the flow rates are in cfm. Measurements for the piping are in inches.

<FONT COLOR="blue"><FONT SIZE="5">0.4 mach = 304 MPH</FONT></FONT>

2" piping
1.57 x 2 = 3.14 sq in
300 cfm = 156 mph = 0.20 mach
400 cfm = 208 mph = 0.27 mach
500 cfm = 261 mph = 0.34 mach
<FONT COLOR="blue">585 cfm max = 304 mph = 0.40 mach</FONT>


2.25" piping
3.9740625 sq in = 1.98703125 x 2
300 cfm = 123 mph = 0.16 mach
400 cfm = 164 mph = 0.21 mach
500 cfm = 205 mph = 0.26 mach
600 cfm = 247 mph = 0.32 mach
700 cfm = 288 mph = 0.37 mach
<FONT COLOR="blue">740 cfm max = 304 mph = 0.40 mach</FONT>


2.5" piping
4.90625 sq in = 2.453125 x 2
300 cfm = 100 mph = 0.13 mach
400 cfm = 133 mph = 0.17 mach
500 cfm = 166 mph = 0.21 mach
600 cfm = 200 mph = 0.26 mach
700 cfm = 233 mph = 0.30 mach
800 cfm = 266 mph = 0.34 mach
900 cfm = 300 mph = 0.39 mach
<FONT COLOR="blue">913 cfm max = 304 mph = 0.40 mach</FONT>


2.75" piping
5.9365625 sq in = 2.96828125 x 2
300 cfm = 82 mph = 0.10 mach
400 cfm = 110 mph = 0.14 mach
500 cfm = 137 mph = 0.17 mach
600 cfm = 165 mph = 0.21 mach
700 cfm = 192 mph = 0.25 mach
800 cfm = 220 mph = 0.28 mach
900 cfm = 248 mph = 0.32 mach
1000 cfm = 275 mph = 0.36 mach
<FONT COLOR="blue">1100 cfm max = 303 mph = 0.40 mach</FONT>


3.0" piping
7.065 sq in = 3.5325 x 2
300 cfm = 69 mph = 0.09 mach
400 cfm = 92 mph = 0.12 mach
500 cfm = 115 mph = 0.15 mach
600 cfm = 138 mph = 0.18 mach
700 cfm = 162 mph = 0.21 mach
800 cfm = 185 mph = 0.24 mach
900 cfm = 208 mph = 0.27 mach
1000 cfm = 231 mph = 0.30 mach
1100 cfm = 254 cfm = 0.33 mach
1200 cfm = 277 mph = 0.36 mach
<FONT COLOR="blue">1300 cfm max= 301 mph = 0.39 mach</FONT>

 

1lb/min = 14.472 cfm

 

maybe these pics will help you speed things along and answer some questions. my advice, just get an 18" long 3.5" ID tube, cut it in half, weld a MAF flange on one, use the other behind the bumper to the air filter connected with a 90 degree silicone coupler through the core support.

 

(Pessure Ratio x 14.7) - 14.7 = boost

http://www.turbobygarrett.com/turbob...o_tech103.html

 

85% of the time I need to replace the things that "I made better". I never learn the first time around.

Whats all those MM's? we speak american over here! lol...

 

good info although I imagine air temp is another factor that needs to be considered in the conversion to g/s. There is also some good info on the Garrett site on this .

That puts the recommended max for
2 " at 306 g/s - approx. 260whp.
2.25" at 387g/s - approx 340whp

So - perhaps the 2" pipe to the IC should be upgraded earlier than I suggested above .

From Garrett

 

That puts the recommended max for
2 " at 306 g/s - approx. 260whp.
2.25" at 387g/s - approx 340whp

how exactly are you calculating this?

 

/\


I used the info you provided here ....

 

I get that part, but not the WHP part, do you have a chart of given g/s to HP numbers?

 

just from doing a few dynos and making the comparison ....

 

well I checked it out on my car tonight while I was doing some routine maintenance. With a rubber elbow and reinforced silicone hose I could get a 3.5" inlet pipe all the way to the motor mount bracket fairly easily. However, I started this by saying "if it were me". I'm funny that way, not suggesting that anyone else should or would do it. As I've proven, it's the summation of incremental improvements combined that net a worthy impact. My car is at 2700# with a full interior. It never could have gotten there if I had the negative mindset that the little bit here and the little bit there doesn't make any difference.

ps: in the calculations above you may have confused boosted/pressurized piping with suction/intake piping. The Corky Bell reference is for pressurized piping, not the turbo inlet/suction piping.


.

 

forgot to mention - if you are on a MM tune . Forget g/s because the way he scales the maf makes that number meaningless for that purpose .

 

would love to get some of that info from you

 

is there anyway to scale it back?

so it becomes meaningful again?

post tune?

 

Agreed - but with a piping system bigger is not always better .


Nope . Was talking about the pressurised pipe to the IC.