for those that are still on the fence on deciding weather to go for supercharger or turbocharger heres a couple things to help make a decision..

for those not so inclined on the compressor map side of the house

LINKAGE TO HOW A TURBO WORKS THANKS TO USMCFIELDMP

HOW-TO-READ A COMPRESSOR MAP

using a map of a T04E 60 trim I will explain all the numbers on the map

1-left side, PRESSURE RATIO
(14.7 + amount of boost) / 14.7 = PR
so to figure out the PR for 8 PSI
(14.7 + 8) / 14.7 = 1.54 PR


2-bottom side, AIRFLOW RATE UNDER BOOST (LB/MIN on this map)
Most methods of calculation your engine's airflow rate will give you the answer in cubic feet per minute (CFM). However most compressor maps measure airflow rate in pounds per minute (LB/MIN). As some of you may know the weight of air varies with the temperature. To convert CFM to LB/MIN use the following numbers.
@ 48 degrees F : (CFM * 0.078125) = LB/MIN
@112 degrees F : (CFM * 0.070318) = LB/MIN
@175 degrees F : (CFM * 0.06251) = LB/MIN

Say for example our airflow rate is 500 CFM , and the temperature is 112 degrees F.
(500 * 0.070318) = 35.16 LB/MIN

*For those of you that know anything about ideal gas law, if you know a better way of explaining how to convert CFM to LB/MIN, your input would be appreciated. But please explain it in "laymans" terms, so that everyone can get a grasp on it.


3-dotted line on far left side of "ovals", SURGE LIMIT
It is important to try and keep yourself on the right side of this dotted line whenever possible. If you fall to the left of this dotted line you will experience compressor surge. This type of compressor surge will occur when there is too much boost, but not enough airflow through the system, usually this is between idle and the point at which full boost is reached. The chirping sound that can be heard is a result of the oscillating air. This sound is often described as a "Snakelike" sound or a che-che-che sound.

*staying in the "surge limit" area for too long could possibly damage your turbo.


4-numbers on far right, 46,020, 69,640, 83,972 etc, COMPRESSOR RPM
This is RPM at which the compressor fans will be turning. an average RPM is between 90,000 and 130,000. The line that branches out from each of these numbers that goes towards the surge limit line shows you the RPM range of the compressor fan across the entire compressor map.


5-78%,75%, 74%, COMPRESSOR EFFICIENCY
This is related to the temp of air and how much it is being heated up as it is being compressed by 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.


6-"Ovals"
I you look closely you will see that the compressor efficiency numbers usually sit right on top of one of these Oval lines. These Ovals show you the boundaries of the compressor efficiency at the different percentiles. Think of it as a topography map that shows you different elevations or changes in elevations. The innermost Oval on the sample T04 E 60" is not labeleb but it is probably 79% or 80%, so any where inside that Oval and you would be operating in the 80% range of that compressor.

 

oh man.. zip the flame suit. Just for making the topic you did. Someone will argue this is not logical or some bs.

 

lol most of the people that did turbo swaps understand the information and can accept it for what it is

 

just grabbed my popcorn...gonna be a good one ...im excited for the tvs as well

 

Yup this is gonna be a good one!

 

Just like I got told last week that engineering principles were irrelevant.

 

lol...

 

i guess no one cares to commit? numbers speak for themselves haha

 

Good info... I always struggled to read/understand compressor maps and never could find the info to LEARN how to read them! THIS will help me out TONS!

 

i try to give back to the community so when i make a "ima leave" thread no one says all u did was showed us how to not slip our clutch....and how to aim projectors what good did u do? lol

 

subscribed must read when not so late and brain is working

 

on the 1320 map i dont see a surge number is this because its a supercharger?

and on the 60 trim map why do the RPM numbers go up and then suddenly drop at the far right? it goes from 150XXX to 13,669


also on top of this info can you add a thread that explains what all the number of a turbo mean....like the trim, what the "r" means, etc

 

The "Inlet Volume Flow" on the TVS map (or on the M62 map)... how do you convert that to lb/min... or how do you use that measurement?

It's funny to calculate my PR on the M62... only to look at the Map and see that I am WAY off the charts.

 

i did crap load of turbo swaps on cars,and i dont get it,lol...ill stick to hands on instead of reading

 

http://www.turbobygarrett.com/turbob...o_tech101.html
TurboByGarrett.com - Turbo Tech 101

 

because thats its effeciency range...no surge numbers because a s/c has "max" cfm's but as we all know a s/c can be spun pass its limits lol...and as for the other turbo stuff...do some homework sucka u can be spoon feed forever lol I LOVE U KY

 

they told me when i get to nuke school if a why isnt explained with the info dont ask why because you dont need to know

 

link added to first post thanks to usmcfieldmp

 

http://store.forcedperformance.net/m...creen=Info_FAQ

http://www.turbobygarrett.com/turbob...o_tech102.html

those are 2 links for mitsu spec turbos and garret spec turbos that deal with A/R trims and such. Have fun Learning!

 

it was in the advanced section and thats some simple stuff that means alot to the right people

also if you want some more indepth info on what raven posted and on some other compressors

click here

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

 

subscribed

 

Well yes... when I posted the first link... I intended for people to click through 101, 102, & 103.

 

hmmm..almost a full day and no responses from the turbo guys....could only mean one thing...lol

 

Did you read through this one any?

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

Goes hand in hand with what you posted... might be a little bit of extra info that you could add in there... like at the bottom, where it explains how to pick the right one for you.

 

there is one other thing to add on reading the compressor map: choke line
that is the line to the far right where the compressor is not building up enough pr and is exceeding the rpm limit of the unit. in which case its time to upgrade to a larger compressor.