Is a bigger blower a better blower?
04-18-2007 | 10:44 AM
#11
TECH Resident
Joined: Oct 2004
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From: TAMPA by way of MIAMI!!!
Originally Posted by BigTex
All blowers and turbos have a compressor map (but the manufacturer may not make the data public), which is a fancy little chart showing how efficient the device is at processing a given amount of air at certain rpms and pressures. What you'd need to do is calculate how much air you need for that 370 motor, how much boost you want to run, how many rpms you want to spin, then.... pick out a blower that will support your maximum needs, but isn't overkill to the point of inefficiency.
Personally, I'd think the whipple 3.3 is too large. The KB 2.8 is probably just about right for a max effort 370. The TVS stuff looks like its going to hold its own too.
For and example, here is a map of the TVS 1900 compressor:
Personally, I'd think the whipple 3.3 is too large. The KB 2.8 is probably just about right for a max effort 370. The TVS stuff looks like its going to hold its own too.
For and example, here is a map of the TVS 1900 compressor:
So does anybody know how to read that damn thing? I just look at that thing and stare at it thinking it's gonna be like one of those optical illusions posters.
04-18-2007 | 11:04 AM
#13
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Joined: Jul 2006
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From: Somewhere around -199C
Originally Posted by firefighter
So does anybody know how to read that damn thing? I just look at that thing and stare at it thinking it's gonna be like one of those optical illusions posters.
YES THEY ARE NOT AS CONFUSING AS IT LOOKS... SEE THE RINGS HOW THEY HAVE 75 73 ETC..... THOSE ARE THE % OF EFFICIENCY... ANOTHERWARDS THE MIDDLE ONE THAT ARE IN THE MAP IS WHERE THE BLOWER MAKES POWER THE MOST EFFICIENTLY.
SO BASICALLY A TURBO IS USUALLY CAPABLE OF MUCH BETTER EFFICIENCY THAN A BLOWER.
DAMN ITS HARD TO EXPLAIN HOW TO GET THOSE NUMBERS THOUGH
04-18-2007 | 11:50 AM
#14
i wouldnt say a turbo is much more efficient. most turbos max out in the 70-80% eff range. take away the hp to drive the blower and that is where the turbos shine.
that map is only hard to read because of the units they are using. on the left side it has pr. that is in bar where 1 bar is atmospheric presure that we see every day. so basicly 1 bar on the pr is what we would call 0psi. 2 bar is what we would call 14.7psi. with that in mind you can figure out what boost presures they are talking about.
now go down to the bottom part of the chart. that is volume of air just like cfm but in a diferent unit. go here http://www.onlineconversion.com/ and try and find the conversion for what they have to cfm. i got to run or i would find it for ya. then once you know the cfm you can do an estimate of how much hp that will support.
because of the conversions it is kind of hard to get the info you want but it is there.
sometimes they thow another set of data on top of that chart that shows you how much hp it takes to run the compresor at all of those diferent points. the upper boost and rpms some of the blowers are over 100hp
that map is only hard to read because of the units they are using. on the left side it has pr. that is in bar where 1 bar is atmospheric presure that we see every day. so basicly 1 bar on the pr is what we would call 0psi. 2 bar is what we would call 14.7psi. with that in mind you can figure out what boost presures they are talking about.
now go down to the bottom part of the chart. that is volume of air just like cfm but in a diferent unit. go here http://www.onlineconversion.com/ and try and find the conversion for what they have to cfm. i got to run or i would find it for ya. then once you know the cfm you can do an estimate of how much hp that will support.
because of the conversions it is kind of hard to get the info you want but it is there.
sometimes they thow another set of data on top of that chart that shows you how much hp it takes to run the compresor at all of those diferent points. the upper boost and rpms some of the blowers are over 100hp
04-18-2007 | 01:03 PM
#15
TECH Junkie
Joined: Mar 2002
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From: memphis tn
04-18-2007 | 01:12 PM
#16
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Joined: Jul 2006
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From: Somewhere around -199C
Originally Posted by parish8
i wouldnt say a turbo is much more efficient. most turbos max out in the 70-80% eff range. take away the hp to drive the blower and that is where the turbos shine.
that map is only hard to read because of the units they are using. on the left side it has pr. that is in bar where 1 bar is atmospheric presure that we see every day. so basicly 1 bar on the pr is what we would call 0psi. 2 bar is what we would call 14.7psi. with that in mind you can figure out what boost presures they are talking about.
now go down to the bottom part of the chart. that is volume of air just like cfm but in a diferent unit. go here http://www.onlineconversion.com/ and try and find the conversion for what they have to cfm. i got to run or i would find it for ya. then once you know the cfm you can do an estimate of how much hp that will support.
because of the conversions it is kind of hard to get the info you want but it is there.
sometimes they thow another set of data on top of that chart that shows you how much hp it takes to run the compresor at all of those diferent points. the upper boost and rpms some of the blowers are over 100hp
that map is only hard to read because of the units they are using. on the left side it has pr. that is in bar where 1 bar is atmospheric presure that we see every day. so basicly 1 bar on the pr is what we would call 0psi. 2 bar is what we would call 14.7psi. with that in mind you can figure out what boost presures they are talking about.
now go down to the bottom part of the chart. that is volume of air just like cfm but in a diferent unit. go here http://www.onlineconversion.com/ and try and find the conversion for what they have to cfm. i got to run or i would find it for ya. then once you know the cfm you can do an estimate of how much hp that will support.
because of the conversions it is kind of hard to get the info you want but it is there.
sometimes they thow another set of data on top of that chart that shows you how much hp it takes to run the compresor at all of those diferent points. the upper boost and rpms some of the blowers are over 100hp
YEAH I HEAR YA PARISH BUT FROM WHAT IVE SEEN I HAVE SEEN BDS UNITS RATED AT ABOUT 55-65% EFFICIENCY THEN YOU TAKE A TURBO AT 70-80 AND IT MAY NOT SEEM LIKE MUCH BUT THAT IS A BIG DIFFERENCE...
THEN AGAIN UNLESS YOU RUN A SMALL ENOUGH TURBO YOUR REALLY GONNA MISS THAT OFF IDLE TORQUE THAT THE POSITIVE DISPLACEMENT BLOWER OFFERS ALSO.
BUT IM DEFINITELY NOT GONNA PRETEND TO KNOW MORE THAN YOU ABOUT THIS.... YOUR TRUCK RUNS 10'S.... MINE WELL... IT RUNS....
04-18-2007 | 04:22 PM
#19
when you are intercooled get a blower that is sized for it
i was reading on some gen 1 truck forums, and their solution for no intercooler for a SC on a carbed motor, roots or centrifugal, is get a bigger blower , because a bigger blower doesnt create as much heat as it doesnt work as hard, like on a BBC if 8psi is giving off too much heat with a 6-71 blower they tell you to just get a 8-71 or 10-71 blower, there were a few runnin a 8-71 blower on SBCs
i was reading on some gen 1 truck forums, and their solution for no intercooler for a SC on a carbed motor, roots or centrifugal, is get a bigger blower , because a bigger blower doesnt create as much heat as it doesnt work as hard, like on a BBC if 8psi is giving off too much heat with a 6-71 blower they tell you to just get a 8-71 or 10-71 blower, there were a few runnin a 8-71 blower on SBCs
