How Do I Figure PR for Turbo Maps ?
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From: Twin Cities
How Do I Figure PR for Turbo Maps ? I'm stuck... How does one figure the Pressure Ratio for the Vertical portion of a compressor Map ?
And once you know how to calculate it wouldn't you have to figure different PR's for each engine RPM and boost levels to really get any usefull info out of the MAP.
I've ordered a GT42 and am having second thoughts about it being large enough for my setup, which is a iron block 408 with 9 to 1 CR which made @ the Flywheel 505HP @5700 and 515TQ at 4600 NA. Dyno'ed it Wednesday. Thinking I'd want to run at least 18lbs of boost to be in center of the compressor map ...Any thoughts
And once you know how to calculate it wouldn't you have to figure different PR's for each engine RPM and boost levels to really get any usefull info out of the MAP.
I've ordered a GT42 and am having second thoughts about it being large enough for my setup, which is a iron block 408 with 9 to 1 CR which made @ the Flywheel 505HP @5700 and 515TQ at 4600 NA. Dyno'ed it Wednesday. Thinking I'd want to run at least 18lbs of boost to be in center of the compressor map ...Any thoughts
You can use this link below.... It has what you are looking for.
http://www.forcedinductions.com/help.htm
Jose
http://www.forcedinductions.com/help.htm
Jose
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From: Twin Cities
Originally Posted by JZ 97 SS 1500
You can use this link below.... It has what you are looking for.
http://www.forcedinductions.com/help.htm
Jose
http://www.forcedinductions.com/help.htm
Jose
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Thats some pretty cool info...
I am thinking of running two of these... I'll have to look up the closest engine to what I'm building and divide by 2 then plot...
http://www.forcedinductions.com/help.htm
That is some kick *** stuff... One of the best laid out sites I have seen for non import turbocharging..
This 408 should be close enough for Ripped..... http://www.forcedinductions.com/consumption408.htm
I am thinking of running two of these... I'll have to look up the closest engine to what I'm building and divide by 2 then plot...
http://www.forcedinductions.com/help.htm
That is some kick *** stuff... One of the best laid out sites I have seen for non import turbocharging..
This 408 should be close enough for Ripped..... http://www.forcedinductions.com/consumption408.htm
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From: Las Cruces, NM
Pressure ratio (PR) = ( atmospheric pressure + boost pressure ) / atmospheric pressure
atmospheric pressure varies with altitude, but at sea level its 14.7 psia
Boost pressure can be gauge pressure - what would read on a gauge
Hope that helps
Gary
atmospheric pressure varies with altitude, but at sea level its 14.7 psia
Boost pressure can be gauge pressure - what would read on a gauge
Hope that helps
Gary
Thread Starter
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Joined: Nov 2001
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From: Twin Cities
Originally Posted by red ws6 99
Pressure ratio (PR) = ( atmospheric pressure + boost pressure ) / atmospheric pressure
atmospheric pressure varies with altitude, but at sea level its 14.7 psia
Boost pressure can be gauge pressure - what would read on a gauge
Hope that helps
Gary
atmospheric pressure varies with altitude, but at sea level its 14.7 psia
Boost pressure can be gauge pressure - what would read on a gauge
Hope that helps
Gary
V8_DSM_V8again, let me know what motor you want added and I will add it to the site. I'm always looking for feedback from the turbo community. Thats what we are here for..
Jose
Jose
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Originally Posted by JZ 97 SS 1500
V8_DSM_V8again, let me know what motor you want added and I will add it to the site. I'm always looking for feedback from the turbo community. Thats what we are here for..
Jose
Jose
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I'm still working on the specs... Static displacement may be close to something already on there... Raised runner heads, huge valves and some other tricks will be the biggest differences... Right now i'm debating the merits of bore and stroke combinations.... With a turbo motor I'm thinking of not stroking at all and focusing funds on the heads, intake and bore since less exotic forged reciprocating assembly is cheaper.. There is reduced less stress on the rods decreased piston speed etc... All these are probably a good idea for an engine. Alot of boost is hard enough on the rods and pistons... no sense in making it worse with stroke... It will have a big fat powerband due to a wider RPM range... My last car had as late of spool up as should be run on the street.... Heh I actually turned on the rally ALS system on my ECU for a while.... Somehow bystanders thought it was interesting... I wonder why...
If it is a peaky engine you need a shift strategy to keep the rpms up.. If it is a "bottomy" engine you need to do it keep them down... If it has a big fat powerband you have alot more leeway.. I have driven cars like that... it rules..
If it is a peaky engine you need a shift strategy to keep the rpms up.. If it is a "bottomy" engine you need to do it keep them down... If it has a big fat powerband you have alot more leeway.. I have driven cars like that... it rules..
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I'm thinking 4.1 bore iron block Ls1 stock stroke...
Witha Scat center counterweight Procomp lightweight billet crank. Think High flowing components and the right cam... Adjustable shaft mounted rockers, solid roller... The works...
Witha Scat center counterweight Procomp lightweight billet crank. Think High flowing components and the right cam... Adjustable shaft mounted rockers, solid roller... The works...