Let's Examine The Gt40
10-18-2003 | 05:13 PM
#41
Senior Member
Joined: Jul 2001
Posts: 273
From: oHIo
See above 
I'm curious as to what sort of flow numbers people take into account when
reading compressor maps for rotary engines. What's a good average lbs min.
corrected flow rate for a large street port 13B RE/W? Trying to match my engine
to a particular turbo with two different compressor options and three turbine/housing combos.
...
Michel
many knowledgable tuners believe it takes 1.92 cubic feet per minute to make one rear wheel hp. 10 lbs per minute equals 144.71 cfm.
there you go.
-howard coleman
30-35 for stock ports - 35-40 on heavily ported motors, on average.
-Ted
reading compressor maps for rotary engines. What's a good average lbs min.
corrected flow rate for a large street port 13B RE/W? Trying to match my engine
to a particular turbo with two different compressor options and three turbine/housing combos.
...
Michel
many knowledgable tuners believe it takes 1.92 cubic feet per minute to make one rear wheel hp. 10 lbs per minute equals 144.71 cfm.
there you go.
-howard coleman
30-35 for stock ports - 35-40 on heavily ported motors, on average.
-Ted
10-19-2003 | 11:33 PM
#43
Thread Starter
Senior Member
Joined: Jul 2001
Posts: 629
From: S. Florida
Ahh excellent...so the 88mm it is. Not sure what Im going to do now...first choice, and cheapest I guess would be to try a different manifold. The old style (it might be the SPL GReddy) header I have now has larger runners than the newer GReddy unit. More surface area;/volume which Im sure does not help spool. I still cant imagine the T78 turbine working better with the GT40 88mm compressor than a matched Garrett turbine. Jason made some great numbers though, with nothing fancy. So Ill probably update the turbo too. When does it end? Is there a new Jaytech web site?
Ok, now in the info you posted (Tony) you list 52 lbs min. while Ted says 35 to 40 for a heavily ported motor. Who is correct?
Tony, do give me a buzz if you come down to sunny Florida. I am actually on the west coast of the state (Naples) but it only takes about an hour to get over to Miami. Your sister has no worries. Im very married
Im actually just outside Louisville, KY on assignment for the next week. Just discovered the high speed connection in my hotel room (the joy!). Suppposed to get down into the 30s on Wednesday, sigh...I dont even own a warm coat!
A few keys on the right side of my keboard dont work as the result of spilling OJ at 35,000 feet. Insert apostrophies where appropriate.
Ok, now in the info you posted (Tony) you list 52 lbs min. while Ted says 35 to 40 for a heavily ported motor. Who is correct?
Tony, do give me a buzz if you come down to sunny Florida. I am actually on the west coast of the state (Naples) but it only takes about an hour to get over to Miami. Your sister has no worries. Im very married
Im actually just outside Louisville, KY on assignment for the next week. Just discovered the high speed connection in my hotel room (the joy!). Suppposed to get down into the 30s on Wednesday, sigh...I dont even own a warm coat!
A few keys on the right side of my keboard dont work as the result of spilling OJ at 35,000 feet. Insert apostrophies where appropriate.
10-20-2003 | 06:58 PM
#46
Senior Member
Joined: Nov 2002
Posts: 102
From: bay area california
I've been comparing the specs on various GT turbos to the Turbonetics Q trim T66. I am basing this on a 1.00 ar T66 since I know of a couple of guys who are using it on a T66 with good results. A GT40R comes the closest, although the compressor turbine pairing in the Garrett catalog seems to use a larger turbine than the T66 with a comparable compressor.
Turbonetics T66 specs(assuming I am reading their catalog correctly)
compressor;
90mm wheel,2.58minor,3.584 major=52 trim
turbine;
78mm, 2.693 minor, 3.111 major=75 trim, 1.00ar
Garrett GT40 Ball bearing standard specs;
(1.) 82mm 50 trim compressor, 77mm 73 trim .94 ar turbine
or
(2.) 88mm 54 trim compressor 77mm 84 trim 1.34ar turbine
QUESTIONS;
How will the first Garrett option spool compared to the T66, and how will the ultimate HP compare? or should I(can I) try to get the larger Garrett compressor with the smaller Garrett turbine (almost the same as a T66 Qtrim) ie
T66-- 90mm 52 trim compressor, 78mm 75 trim 1.00ar turbine
GT40-88mm 54 trim compressor, 77mm 73 trim .94ar turbine
So, I think I would start with the GT40R that is closest to the T66, and maybe go to the larger exhaust housing if power was too low. Carl Byck
BTW anyone know the specs on the GT40R jason is selling?
Turbonetics T66 specs(assuming I am reading their catalog correctly)
compressor;
90mm wheel,2.58minor,3.584 major=52 trim
turbine;
78mm, 2.693 minor, 3.111 major=75 trim, 1.00ar
Garrett GT40 Ball bearing standard specs;
(1.) 82mm 50 trim compressor, 77mm 73 trim .94 ar turbine
or
(2.) 88mm 54 trim compressor 77mm 84 trim 1.34ar turbine
QUESTIONS;
How will the first Garrett option spool compared to the T66, and how will the ultimate HP compare? or should I(can I) try to get the larger Garrett compressor with the smaller Garrett turbine (almost the same as a T66 Qtrim) ie
T66-- 90mm 52 trim compressor, 78mm 75 trim 1.00ar turbine
GT40-88mm 54 trim compressor, 77mm 73 trim .94ar turbine
So, I think I would start with the GT40R that is closest to the T66, and maybe go to the larger exhaust housing if power was too low. Carl Byck
BTW anyone know the specs on the GT40R jason is selling?
