My NEW 5" thick FMIC mounted... PE TT 6MT Sedan
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Joined: Aug 2003
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From: Los Angeles, CA
Originally Posted by Hydrazine
If you are saying boost is regulated by a sensor before the IC, it should result in a pressure recovery at the plenum.
If the sensor regulates (hypothetically) to a maximum of 13 PSIG, and the new IC drops 0.5 PSID less than the old IC, this should result in a 0.5 PSI gain at the plenum.
This is only pressure. It does not say anything about the new density delta which is also likely to have improved too.
If the sensor regulates (hypothetically) to a maximum of 13 PSIG, and the new IC drops 0.5 PSID less than the old IC, this should result in a 0.5 PSI gain at the plenum.
This is only pressure. It does not say anything about the new density delta which is also likely to have improved too.
Boost is regulated by the pre-IC pressure, which was previously elevated vs. post-IC pressure (purporting pressuredrop with the old IC at high boost levels). But won't improved (increased) DR make a direct comaprison impossible if you look/measure post-IC (in-manifold) pressure only.
DR=PRsys*[(Tamb+460)/(IAT+460)]
PRsys (systemi PR , including the IC press drop) will go up since the boost wil be regulated higher (due to less backup from the IC - so Pin/Pout relative to the IC is closer to 1) and due to the lower IC drop, while DR will go down due to lower IAT. Looks to me as though there are too many variables to make direct precise conclusions.
Be that as it may, the power increase is noticeable even without a change in timing. This is jsutified as the MFR (mass flow rate) has definitely improved, the only question is by how much.
MFR=VFR(2.703*Pamb)/(Tamb+460)*DR
VFR=volumetric flow rate (unchanged - fn of engine displacement and VE)
PRsys=systemic PR, including the IC pressure drop.
We'll know soon enough. Maybe I can come by one day to throw this baby on teh dyno, Tony. Let me know when it's good day to do that.
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Joined: Feb 2007
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From: Sunland
Originally Posted by 1superg
sweet work Gurgen, now get a job...
So for all who know him for his automotive/tuning/science expertice, add brilliant doctor to the list.
Congrats on all your success!
Nice work...and that was fast! We were just talking about this over the weekend, and bam..its installed. 
Do you still want me to check on that Greddy charge pipe, or did you find a substitute?
Do you still want me to check on that Greddy charge pipe, or did you find a substitute?
Originally Posted by GurgenPB
I see what you are saying.
Boost is regulated by the pre-IC pressure, which was previously elevated (Previously elevated? - It should be directly regulated to a fixed value you set at the boost controller regardless of IC delta P) vs. post-IC pressure (purporting pressuredrop with the old IC at high boost levels). But won't improved (increased) DR (DR?)make a direct comaprison impossible if you look/measure post-IC (in-manifold) pressure only. (I would think not. You have data loged the plenum pressure both before and after the new IC. Regardless of MFR, any change in IC pressure drop should be measurable at the plenum if the inlet pressure at the IC remains regulated and constant. And I would expect you are getting better pressure and MFR performance with the new IC. So you should be able to measure a change in plenum pressure and engine output.)
DR=PRsys*[(Tamb+460)/(IAT+460)]
PRsys (systemi PR , including the IC press drop) will go up since the boost wil be regulated higher (due to less backup from the IC - so Pin/Pout relative to the IC is closer to 1) and due to the lower IC drop, while DR will go down due to lower IAT. Looks to me as though there are too many variables to make direct precise conclusions.
Be that as it may, the power increase is noticeable even without a change in timing. This is jsutified as the MFR (mass flow rate) has definitely improved, the only question is by how much.
(if MFR changed by any substantial amount, it should register in your A/F ratio. You could back out a rough delta MFR from that)
MFR=VFR(2.703*Pamb)/(Tamb+460)*DR
VFR=volumetric flow rate (unchanged - fn of engine displacement and VE)
PRsys=systemic PR, including the IC pressure drop.
We'll know soon enough. Maybe I can come by one day to throw this baby on teh dyno, Tony. Let me know when it's good day to do that.
Boost is regulated by the pre-IC pressure, which was previously elevated (Previously elevated? - It should be directly regulated to a fixed value you set at the boost controller regardless of IC delta P) vs. post-IC pressure (purporting pressuredrop with the old IC at high boost levels). But won't improved (increased) DR (DR?)make a direct comaprison impossible if you look/measure post-IC (in-manifold) pressure only. (I would think not. You have data loged the plenum pressure both before and after the new IC. Regardless of MFR, any change in IC pressure drop should be measurable at the plenum if the inlet pressure at the IC remains regulated and constant. And I would expect you are getting better pressure and MFR performance with the new IC. So you should be able to measure a change in plenum pressure and engine output.)
DR=PRsys*[(Tamb+460)/(IAT+460)]
PRsys (systemi PR , including the IC press drop) will go up since the boost wil be regulated higher (due to less backup from the IC - so Pin/Pout relative to the IC is closer to 1) and due to the lower IC drop, while DR will go down due to lower IAT. Looks to me as though there are too many variables to make direct precise conclusions.
Be that as it may, the power increase is noticeable even without a change in timing. This is jsutified as the MFR (mass flow rate) has definitely improved, the only question is by how much.
(if MFR changed by any substantial amount, it should register in your A/F ratio. You could back out a rough delta MFR from that)
MFR=VFR(2.703*Pamb)/(Tamb+460)*DR
VFR=volumetric flow rate (unchanged - fn of engine displacement and VE)
PRsys=systemic PR, including the IC pressure drop.
We'll know soon enough. Maybe I can come by one day to throw this baby on teh dyno, Tony. Let me know when it's good day to do that.
Last edited by Hydrazine; Jul 3, 2007 at 11:35 AM.
Thread Starter
Joined: Aug 2003
Posts: 1,211
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From: Los Angeles, CA
Originally Posted by 1superg
To all that don't know, Dr. Gurgen is about to embark on his medical career after taking his board exams. He is currently a bum, but not for long, he will dispatching Viagra, Cialis and other life saving drugs to me and other gimps.
So for all who know him for his automotive/tuning/science expertice, add brilliant doctor to the list.
Congrats on all your success!
So for all who know him for his automotive/tuning/science expertice, add brilliant doctor to the list.
Congrats on all your success!
LOL jef.....ROFL..seriously..
That's an inside joke, everybody, these guys think that I look like Alfred Molina...lol
Thread Starter
Joined: Aug 2003
Posts: 1,211
Likes: 1
From: Los Angeles, CA
Originally Posted by Sharif@Forged
Nice work...and that was fast! We were just talking about this over the weekend, and bam..its installed.
Do you still want me to check on that Greddy charge pipe, or did you find a substitute?
Do you still want me to check on that Greddy charge pipe, or did you find a substitute?
I know! I talked to you the day before...and we were oly gonna test fit it that day..rest is history.
Yes, please do check on the price if you can please, just the big pipe and not the second one that bolts up to the maf housing, working on smth else to replace it (bigger MAF! ...more info later).
Thread Starter
Joined: Aug 2003
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From: Los Angeles, CA
Originally Posted by Hydrazine
Systemic PR and DR? Please define.
DR= Density ratio. DR=PRsys[(Tamb+460)/(IAT+460)]
The temps are being converted to degrees R (Rankin)...hence the +460 vs +273.15 to obtain the absolute pressure. So all "T" values are in deg F, while P's in psi.
IAT is the post-IC temperature, after it was heated by the compressor and cooled down by the IC (again, other heat transfers ignored).
IAT is sometimes referred to as Tout, while Tamn is referred to as Tin, but I changed things around a bit for clarity (in case of Tamb), and to avoid confusing IAT with Tout (whereas Tout is used for comrpessor outlet air temps).
Thread Starter
Joined: Aug 2003
Posts: 1,211
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From: Los Angeles, CA
Originally Posted by Hydrazine
Happy 4th of July everyone!
I'm out'a here. Going off to San Diego with the wife and daughter.
I'm out'a here. Going off to San Diego with the wife and daughter.
Originally Posted by GurgenPB
PRsys = Pressure Ratio in the system...i.e. pressure ration developed by the compressor minus the pressure drop in the ic (and technically the press drop through the piping...but ignoring that forthe moment).
DR= Density ratio. DR=PRsys[(Tamb+460)/(IAT+460)]
The temps are being converted to degrees R (Rankin)...hence the +460 vs +273.15 to obtain the absolute pressure. So all "T" values are in deg F, while P's in psi.
DR= Density ratio. DR=PRsys[(Tamb+460)/(IAT+460)]
The temps are being converted to degrees R (Rankin)...hence the +460 vs +273.15 to obtain the absolute pressure. So all "T" values are in deg F, while P's in psi.
The first few pages was great then this
You guys are giving me a headache with all this formula
Good thread and very informative. Only if you can absorb all these DR, PR and T stuff
