RattyTuned

whats up guys i was just wondering what size hardpiping everyones using?

BigMike0147

I think for most "lower horsepower" setups a 2.5" system would work. Some people run 2" on their hot side also and 2.5" on cold side. I think you need to be flowing quite a bit of air to require anything bigger.

Dynamic Performance Racing

It also depends on your set up and what your power goals are. Care to share your set up and power goals?

Turbo-LS

iTrader: (4)

you want to run the smallest possible without going over a certain air speed. 304 MPH or 0.4 mach is the point at which airflow meets increased resistance (drag) and flow losses are experienced.

Depending on which turbo your running and what hp your looking for will determine piping size. to small is a restriction and to larger is laggy. generally for the average setup 2.25-2.5" is what works

here is info i found on mach speeds of certain size piping relavent to cfm flow

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
585 cfm max = 304 mph = 0.40 mach


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
740 cfm max = 304 mph = 0.40 mach


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
913 cfm max = 304 mph = 0.40 mach


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
1100 cfm max = 303 mph = 0.40 mach


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
1300 cfm max= 301 mph = 0.39 mach

BigMike0147

Great info TurboLS. Do you happen to know what the air speeds/cfm equilibrate into as far as HP? I know that there are some general rules of thumb out there.

Dynamic Performance Racing

This.

Like I said earlier, it depends on your power goals and set up.

Wow... alot of info there! lol

On our SFWD Civic, we have a back door setup from our turbo (Precision 7280) and 4" Cold Side. No lag issues there but we are running 45psi at the track. lol

DelSolMarine

Whatever the size is on your turbos compressor...

For example my setup is a 6265 turbo with 2.5 inch charge piping going to a 64mm (2.5 inch) throttle body...

There is 2.5 inches of volume coming out the turbo whats the point of using 3 inches of space? idk makes sense to me.

92frostwhtdb2

your logic would make sense for some but not all cases.mine as a example i have a e-cover sc61 with a 2" outlet i run 2.5in piping hot and cold side..my turbo is pushing 61lbsmin 2" isnt going to suffice

Bix VT

This will show you how to calculate how much CFM your engine will require at a given RPM and pressure ratio, as well as teach you how to read/graph a compressor map.

I take no credit for the information below, it was originally posted by BlueShadow.

*************************

What you need to do is find you airflow rate based on : your desired boost (PSI) engine size and engine redline. you need to find your Airflow rate at two points first point is at redline second point is usually at 75% of redline or where ever the compressor hits full boost, whichever is at a lower RPM. All you need to know is basic math, add, subtract, multiply and divide. you'll deal with different units of measurement (lb,cfm,psi) lets start:

Basics you will use these numbers later on
PRESSURE RATIO = (14.7 + your desired PSI) / 14.7 = PR
convert CFM to LB per MIN = CFM x 0.070318 = LB/MIN (@ sea level and 112 degrees*)
LITERS TO CUBIC INCHES DISPLACEMENT = # of L's x 61
CFM = Cubic Feet per Minute

now using my car as an example:
2.2L (134.2 cid), 7400 Redline, desired boost is 10 PSI

#1 CALCULATING AIRFLOW RATE AT REDLINE and 10 PSI
cid = Cubic Inches Disp.
VE = Volumetric efficiency in percent
.5 = (given) 4-stroke engine fills cylinder only on one-half the revolutions
1728 = converts cubic inches to cubic feet

Airflow in CFM = (cid x rpm x .5 x VE%) / 1728 = CFM no boost
CFM x PR = CFM under boost


so for my Lude:
PR = (14.7 + 10 ) / 14.7 = 1.69
Airflow = (134.2 x 7400 x.5 x .95) / 1728 = 272.99 CFM (no boost)
272.99 x 1.69 = 461.21 CFM under 10 PSI

now since most compressor maps have their flow rates in LB/MIN we need to convert CFM to LB/MIN. A cubic feet of air (length+width+height) weighs different at diff. Altitudes and different temperatures. to simplify it well just assume we are at sea level and the air temp is 112 *. the conversion number is 0.070318.

so for CFM TO LB/MIN = CFM x 0.070318 = LB/MIN
461.21 x 0.070318 = 32.44 LB/MIN

so here we have:
BASIC ENGINE FLOW RATE = 272.99 CFM
ENGINE FLOWRATE with 10 PSI = 461.21 CFM (32.44 LB/MIN)
PRESSURE RATIO (PR) = 1.69

so now we know our flow rate in LB/MIN
a 2.2L with 10 PSI of boost at 7400 RPM (redline)
flow rate = 32.33 pounds of air per minute (LB/MIN)
PR = 1.69
with me still? this is POINT NUMBER ONE. now we do the same for 75% of redline and 50% of redline.

#2 CALCULATING AIRFLOW RATE AT 75% RPM RANGE

now we will find the airflow rate at 75% redline = 5550 RPM (0.75 x 7400 = 5550)

(134.2 x 5550 x .5 x .95) / 1728 = 204.74 CFM no boost
204.74 x 1.69 = 346.02 CFM under 10 PSI

346.02 x 0.70318 = 24.34 LB/MIN

BASIC ENGINE FLOW RATE = 204.74 CFM
ENGINE FLOWRATE with 10 PSI = 346.02 CFM (24.34 LB/MIN)
PRESSURE RATIO (PR) = 1.69

#3 CALCULATING AIRFLOW RATE AT 50% RPM RANGE

As you may already know the point at which the compressor reaches full boost is largely determined by the Turbine side. but I usually calculate a third point just incase. I plot this third point on the compressor map this way if boost comes way early (50% redline) I know where I lie on the map.

50% of redline = 3700 RPM (0.50 x 7400 = 3700)
(134.2 x 3700 x .5 x .95) / 1728 = 136.50 CFM no boost
136.5 x 1.69 = 230.69 CFM under 10 PSI
239.69 x 0.070318 = 16.23 LB/MIN

BASIC ENGINE FLOW RATE = 136.5 CFM
ENGINE FLOWRATE with 10 PSI = 230.69 CFM (16.23 LB/MIN)
PRESSURE RATIO (PR) = 1.69

GATHER YOUR DATA

we have just figured out our engine's airflow rate at 3 RPM points (redline, 75% and 50%) you only need 2 at the minimum but you can use as many points as you want.

<U>POINT 1 (7400 RPM)</U>

FLOWRATE with 10 PSI = 461.21 CFM (32.44 LB/MIN)
PRESSURE RATIO (PR) = 1.69

<U>POINT 2 (5550 RPM)</U>

FLOWRATE with 10 PSI = 346.02 CFM (24.34 LB/MIN)
PRESSURE RATIO (PR) = 1.69

<U>POINT 3 (3700 RPM)</U>

FLOWRATE with 10 PSI = 230.69 CFM (16.23 LB/MIN)
PRESSURE RATIO (PR) = 1.69

these are the three points you will start referencing onto the different compressor maps, ideally you want all three to be within the highest percentile in the compressor map.

using this map of a T04E 60 trim first let me explain all the numbers on the map
1-left side, pressure ratio (how much boost you're running)
2-bottom side, airflow rate (LB/MIN on this map)
3-dotted line on far left side of "ovals", surge limit (if any of your points are to the left of this line you'll get compressor surge)
4-numbers on far right, 46020, 69640, 83972 etc, compressor fan RPM (yikes)
5-78%,75%, 74%, compressor efficiency, this is related to the temp of the air in the compressor, a low number (60%) means that the compressor is heating the air more a high number, (78%) means the air is not heated as much when it is compressed.


NOW all you have to do is take the each RPM point and put them on the compressor map, use the airflow rate and PR, wherever they intersect is where the point will go. ideally you want all points to be in the highest Comp. Eff. %, especially the redline and the 75% redline points.

go ahead and give it a try, but thats pretty much how you select compressors if any of the points lie:
-in a low Comp Eff %
-in the surge limit
-too high a Comp. RPM
you need to look at a different Compressor map cause the one your looking at is the wrong size, each Compressor trim has its own compressor map.

Turbo-LS

iTrader: (4)

Very good information in here. Basically if you have an average turbo with an e cover you can run 2-2.25" piping. for an oversized wheel in an e cover you will need to run 2.25-.5" and for average sized wheel in an s cover 2.25-2.5 and for larger wheels in an s cover 2.5-2.75" after that really your on your own and probably looking at 3" and up.

On my old track car i ran 2.5" hotside and 3" coldside with a 62-1 and it worked fine but it probably would have been more benificial to the setup if i ran 2.5" for the whole thing. The goal is to have more airspeed without hitting that limiting factor of .40 mach

Dynamic Performance Racing

Great read! Thanks for the info!

DelSolMarine

I agree that running 2.5 inch piping makes since your situation because not only does it look better, but the charge pipe kits are more available, however if 2" of volume is coming out the compressor outlet why do you need more that 2 inches after it if that is all the volume coming out the compressor?

Turbo-LS

iTrader: (4)

Just because the turbo outlet is only two inches doesnt mean thats all the amount of air coming out of it. Thats such a short distance it really doesnt dictate the charge pipe size. You can have a turbo in an E cover which is 2" outlet that flows 60+lbs/min and that will need 2.25-2.5 preferably 2.5 or you could have a smaller wheel e cover that only flows 46lbs/min which 2-2.25 would be fine

m3tech95

This is well on its way to being one of those threads that people will google in 2018 for information on intercooler piping size & application.....great info.

RattyTuned

thanks alot guys really appreciate it! but my setups a pretty simple setup
lsv stock sleeve/bore
manley flat top pistons
manley h beams
pte6262 .63 ar
havent decided on intake manifold or throttle body yet
ill most likely be running a ramhorn

i dont know what my setup is gonna be yet im working on the motor as of now motor shall be done by next week ill keep you guys posted but thanks again guys

RattyTuned

So a noob actually posted a useful thread for later generations lmao.

Turbo-LS

iTrader: (4)

Ratty with a 6262 your going to want to run a2.5" charge pipes for sure

Dynamic Performance Racing

I hope you at least get a Full-Race ramhorn manifold! Best ones out in the market!

Sorry... off topic. But yes, great information on this thread!

RattyTuned

Thats what im most definantly running. now i have a few questions about intakes which would you guys suggest skunk 2 or edelbrock x and mate it with which throttlebody?

darkhorizon

I make a touch over 650whp with 2inch pipe out of a pt6776.

Turbo-LS

iTrader: (4)

Your running 2" charge pipes on a pt67??? Talk about restriction

Ratty - a skunk2 will give more midrange power and the victor x will give more top end. That being said I've run both and like the performance out of the victor x. Larger turbos don't spool that early and the higher flowing manifold really will compliment the 6262? There is also the bbk or Magnus and if you really wanna spend money there's kinsler units too

DelSolMarine

LOL this isnt even logical

RattyTuned

the cars gonna be more of a street car it will definantly see the track alot so what would i rather shoot for more topend or midrange? idk if thats a stupid question lolol just asking

Turbo-LS

iTrader: (4)

My car doesnt ever see the track, it will now that i moved to texas but im very pleased with the responsiveness of my engine with the victor and it pulls like a bastard from 7000-9200 with ctr cams

4cylfiend

iTrader: (1)

Thanks for the pic. Im gonna go to the bathroom now.