What would you do? Compressor related.
#1
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What would you do?
What I have:
T3/T4 Chinacharger Compressor
2.25" Inducer
3.00" Exducer
.50 A/R Housing 2.50" inlet
T70 Chinacharger Compressor
2.07" Inducer
3.00" Exducer
.70 A/R Housing 4.00" inlet
Would you open the inlet on the T70 compressor housing and run the 2.25" compressor wheel? Run the T70 compressor wheel as is? Run the 2.25" compressor wheel with the .50 A/R housing?
Personally I am leaning towards running the T70 compressor housing with the 2.25" compressor wheel. Any experts here see an upside or downside to any of the configurations.
I will be running the T70 turbine, which is a rather large T3 turbine with a .84 A/R divided tang housing. It makes the previous .63 A/R housing look tight and restrictive. As a matter of fact the turbine wheel won't fit in the .63 housing.
Mark
What I have:
T3/T4 Chinacharger Compressor
2.25" Inducer
3.00" Exducer
.50 A/R Housing 2.50" inlet
T70 Chinacharger Compressor
2.07" Inducer
3.00" Exducer
.70 A/R Housing 4.00" inlet
Would you open the inlet on the T70 compressor housing and run the 2.25" compressor wheel? Run the T70 compressor wheel as is? Run the 2.25" compressor wheel with the .50 A/R housing?
Personally I am leaning towards running the T70 compressor housing with the 2.25" compressor wheel. Any experts here see an upside or downside to any of the configurations.
I will be running the T70 turbine, which is a rather large T3 turbine with a .84 A/R divided tang housing. It makes the previous .63 A/R housing look tight and restrictive. As a matter of fact the turbine wheel won't fit in the .63 housing.
Mark
#2
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No one has an opinion... Well I did a little research. Seems that the Chinacharger T70 has basically a 46 trim wheel vs the T3/T4's 57 trim wheel.
Surprisingly enough, large A/R's on the compressor side do little to effect much other than low vs high boost performance and are largely irrelevant. They will not affect compressor air flow much. Inducer and Exducer sizes are much more important.
Obviously higher trim wheels flow more air, but how much more?
Well looking at Garrett's website, the Chinacharger T70 compressor is a clone of the 76 series compressors. The GT2876R compressor in the 48 trim with a .70 A/R to be exact.
http://www.turbobygarrett.com/turbob...R_705330_1.htm
Garrett claims this compressor is good for 480 HP.
The Chinacharger T3/T4 57 Trim is very close in specs with the GT3076R 56 trim with a .60 A/R and since A/R on the compressor side is not much of a factor I am going to trust that map. Garrett claims that the 56 Trim 76 series compressor is good for 525 HP and below is a map for that. Roughly a 45 HP difference in compressors.
http://www.turbobygarrett.com/turbob..._700382_12.htm
Mark
Surprisingly enough, large A/R's on the compressor side do little to effect much other than low vs high boost performance and are largely irrelevant. They will not affect compressor air flow much. Inducer and Exducer sizes are much more important.
Obviously higher trim wheels flow more air, but how much more?
Well looking at Garrett's website, the Chinacharger T70 compressor is a clone of the 76 series compressors. The GT2876R compressor in the 48 trim with a .70 A/R to be exact.
http://www.turbobygarrett.com/turbob...R_705330_1.htm
Garrett claims this compressor is good for 480 HP.
The Chinacharger T3/T4 57 Trim is very close in specs with the GT3076R 56 trim with a .60 A/R and since A/R on the compressor side is not much of a factor I am going to trust that map. Garrett claims that the 56 Trim 76 series compressor is good for 525 HP and below is a map for that. Roughly a 45 HP difference in compressors.
http://www.turbobygarrett.com/turbob..._700382_12.htm
Mark
Last edited by Markp; 06-07-2007 at 08:05 AM.
#3
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What are you aiming to achieve with the change? Sounds like you're wanting more top end power (given the rpms you spin). I'd stick with t4 compressor and wheel if you're doing the t70 hot side - assuming you're buying another complete turbo. See what that does for the top end, and what's loss in lower rpm. Then if you want more you can swap the cold side stuff on the manifold.
#4
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What are you aiming to achieve with the change? Sounds like you're wanting more top end power (given the rpms you spin). I'd stick with t4 compressor and wheel if you're doing the t70 hot side - assuming you're buying another complete turbo. See what that does for the top end, and what's loss in lower rpm. Then if you want more you can swap the cold side stuff on the manifold.
Mark
#6
Boost Czar
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what's your mass airflow and how much are you going to boost with it? the smaller wheel looks the best at around 18-19psi and 35 lb/min, the larger wheel is a bit more efficent with more PR, but looks to be designed for more Mass Flow as the shape is a little wider....
#7
2 Props,3 Dildos,& 1 Cat
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Believe it or not, I considered a GT3076R when I picked up my 2876R... but for now I'm happy. I think more would just mean lag, not top end.
I mean 230-240 rwhp at under 10psi is pretty ok.
I mean 230-240 rwhp at under 10psi is pretty ok.
#8
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what's your mass airflow and how much are you going to boost with it? the smaller wheel looks the best at around 18-19psi and 35 lb/min, the larger wheel is a bit more efficent with more PR, but looks to be designed for more Mass Flow as the shape is a little wider....
Mark
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