Horsepower vs Boost Pressure comparison for Greddy based turbos
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Boosted Kiwi
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From: Y-cat-o NZ
Ok I'm in a random ideas kinda mood...so please bear with me. This is kind of a cross discussion of this thread and the one about your melted housing.
Do the exhaust ports on the center and outer housings share the same shape where the rotor passes them? Or are they smaller for the center housing and the shared ports?
What would happen if I were to make a manifold where the center port was deidicated to the wastege? It would eliminate flow through those ports alltogether until the wastegate cracks. Would it then be subjected to less pressure/resistance under higher boost? Or would forcing all the bleeding of pressure through the center actually create more heat and/or boost creep?
Do the exhaust ports on the center and outer housings share the same shape where the rotor passes them? Or are they smaller for the center housing and the shared ports?
What would happen if I were to make a manifold where the center port was deidicated to the wastege? It would eliminate flow through those ports alltogether until the wastegate cracks. Would it then be subjected to less pressure/resistance under higher boost? Or would forcing all the bleeding of pressure through the center actually create more heat and/or boost creep?
Not sure what your idea would do but at high flow rates I doubt it would help .
I divide by zero
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My line of thought was to force the flow through the less restrictive runners. And when the wastegate cracks the restrictive runners would be under less backpressure and thus less of a restriction. Kinda making the renesis work like an Rx7 engine most of the time. Just random theorycrafting
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This is a comparison of a stock greddy(wrung out to it's max) vs a 57trim
I thought it interesting because the result is pretty much identical bar that last 1500rpm .
I thought it interesting because the result is pretty much identical bar that last 1500rpm .
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Why should a flow restriction in the exhaust make things better? I have three thing I do not understand:
1. I do not understand why you have more torque/power between 4500 - 7900rpm. It does not follow difference in boost
2. I do not understand why do you get higher boost in midrange with flow retriction
3. I do not understand why you make more power at the same pressure between 6- 7000rpm
Why?!?
Education please.
1. I do not understand why you have more torque/power between 4500 - 7900rpm. It does not follow difference in boost
2. I do not understand why do you get higher boost in midrange with flow retriction
3. I do not understand why you make more power at the same pressure between 6- 7000rpm
Why?!?
Education please.
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Boosted Kiwi
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From: Y-cat-o NZ
Why should a flow restriction in the exhaust make things better? I have three thing I do not understand:
1. I do not understand why you have more torque/power between 4500 - 7900rpm. It does not follow difference in boost
2. I do not understand why do you get higher boost in midrange with flow retriction
3. I do not understand why you make more power at the same pressure between 6- 7000rpm
Why?!?
Education please.
1. I do not understand why you have more torque/power between 4500 - 7900rpm. It does not follow difference in boost
2. I do not understand why do you get higher boost in midrange with flow retriction
3. I do not understand why you make more power at the same pressure between 6- 7000rpm
Why?!?
Education please.
It wasn't a restriction , it was actually the removal of a restriction which is why i believe the extra power was there . Also notice there was LESS power in the lower rpms - at NA flow ranges .
The answer to the higher boost question is just that the boost controller was set higher .
Will be testing this more fully in the coming months .
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Thought this might be interesting to Greddy / Greddy upgrade owners to see what sort of power they can expect to make at various boost levels .
These dynos were all of the same car on the same dyno with more or less the same turbo setup .
Note that boost is not constant for any of the runs so this needs to be looked at in conjunction with the whp result .
These dynos were all of the same car on the same dyno with more or less the same turbo setup .
Note that boost is not constant for any of the runs so this needs to be looked at in conjunction with the whp result .
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Sep 30, 2015 01:53 PM
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