Holy Big Turbos Batman...
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That's not always the case Chad. Typically people don't play with compressor side ARs and more so turbine side ARs to change exactly what you're speaking of. With two of those turbos he'll have more power in those turbos available than he'll use unless he builds a race motor and pushes them HARD.
Also, a 3.25" inducer? Maybe you mean inlet? A 3.25" inducer or 82.xmm turbo would flow well over a 1,000hp EACH. Did you go single turbo??
Also, a 3.25" inducer? Maybe you mean inlet? A 3.25" inducer or 82.xmm turbo would flow well over a 1,000hp EACH. Did you go single turbo??
Originally posted by cjv
sharkster,
That is a very low a/r ratio. It is great for jack rabbit starts and it will definitely eliminate lag. An example, a 68 a/r would be great for jack rabbit starts. It will also start to run out of steam at around 5500 rpm's. I guess it all depends on what you want out of the car.
I am using 3-1/4" inducer diameters. What are these?
sharkster,
That is a very low a/r ratio. It is great for jack rabbit starts and it will definitely eliminate lag. An example, a 68 a/r would be great for jack rabbit starts. It will also start to run out of steam at around 5500 rpm's. I guess it all depends on what you want out of the car.
I am using 3-1/4" inducer diameters. What are these?
Can't get the calipers today (locked up as the guys went home) but all I know is these mammas is biggie size.... Todd/Mike since I got the big mac meal where's my supersize cola and fries dammit
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Originally posted by blunt
That's not always the case Chad. Typically people don't play with compressor side ARs and more so turbine side ARs to change exactly what you're speaking of. With two of those turbos he'll have more power in those turbos available than he'll use unless he builds a race motor and pushes them HARD.
Also, a 3.25" inducer? Maybe you mean inlet? A 3.25" inducer or 82.xmm turbo would flow well over a 1,000hp EACH. Did you go single turbo??
That's not always the case Chad. Typically people don't play with compressor side ARs and more so turbine side ARs to change exactly what you're speaking of. With two of those turbos he'll have more power in those turbos available than he'll use unless he builds a race motor and pushes them HARD.
Also, a 3.25" inducer? Maybe you mean inlet? A 3.25" inducer or 82.xmm turbo would flow well over a 1,000hp EACH. Did you go single turbo??
If boost rise is sluggish. the ratio is too large. In extreme cases, the ratio gets so big the turbo can't turn fast enough to produce the required boost. If the ratio is too small, the turbo gets into boost so quickly that the vehicle becomes almost undriveable - and on top, it will feel like a choked up normally aspirated engine that's under-carbureted. Also, what equates to a low or high A/r ratio varies by turbine series and engine displacement. The TO4 style turbo on a typical 350 ci engine:
Operating Range............A/R Ratio
Low-end.........................0.58
Midrange........................0.69-0.81
High-rpm........................0.96
Last edited by cjv; Oct 12, 2004 at 09:16 AM.
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Originally posted by Matt Fresh
Yes I am running Kevin's SII turbos, but they have been modified with an even larger turbine. I dont want to run 100 oct. mixture all the time, w/o it the ZC turbos just arent worth it for me yet. When I get rid of my M3 and buy another car that can put a smile on my face similar to my 996TT I will upgrade to ZC turbos. I just drove Dan Aspesi's car making well over 700bhp today and let me tell you something... IT IS REDICULOUS!!!
Yes I am running Kevin's SII turbos, but they have been modified with an even larger turbine. I dont want to run 100 oct. mixture all the time, w/o it the ZC turbos just arent worth it for me yet. When I get rid of my M3 and buy another car that can put a smile on my face similar to my 996TT I will upgrade to ZC turbos. I just drove Dan Aspesi's car making well over 700bhp today and let me tell you something... IT IS REDICULOUS!!!
Matt where did you get your KKK24's installed at?
Also who is Dan Aspesi, is he in Pasadena, I'm looking for a new seat of Turbos to replace my 16/24 hybrids, not fast enough, you know the feeling...Thanks....
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Originally posted by toddstacky
Also who is Dan Aspesi, is he in Pasadena
Also who is Dan Aspesi, is he in Pasadena
Craig
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Originally posted by cjv
You are correct, the 3.35" is the inlet. They will definitely have power, however with that a/r ratio it will be all downhill way before it ever gets close to redline.
If boost rise is sluggish. the ratio is too large. In extreme cases, the ratio gets so big the turbo can't turn fast enough to produce the required boost. If the ratio is too small, the turbo gets into boost so quickly that the vehicle becomes almost undriveable - and on top, it will feel like a choked up normally aspirated engine that's under-carbureted. Also, what equates to a low or high A/r ratio varies by turbine series and engine displacement. The TO4 style turbo on a typical 350 ci engine:
Operating Range............A/R Ratio
Low-end.........................0.58
Midrange........................0.69-0.81
High-rpm........................0.96
You are correct, the 3.35" is the inlet. They will definitely have power, however with that a/r ratio it will be all downhill way before it ever gets close to redline.
If boost rise is sluggish. the ratio is too large. In extreme cases, the ratio gets so big the turbo can't turn fast enough to produce the required boost. If the ratio is too small, the turbo gets into boost so quickly that the vehicle becomes almost undriveable - and on top, it will feel like a choked up normally aspirated engine that's under-carbureted. Also, what equates to a low or high A/r ratio varies by turbine series and engine displacement. The TO4 style turbo on a typical 350 ci engine:
Operating Range............A/R Ratio
Low-end.........................0.58
Midrange........................0.69-0.81
High-rpm........................0.96
In general the turbine inlet pressure (TIP) goes up with a smaller A/R. This means that the pressure available to drive the compressor is available earlier, but can be become too high (proportional to intake manifold pressure) at a lower rpm.
A good rule of thumb is to size the compressor(s) to the realistic hp expectations. Than balance the TIP by changing turbine A/R or turbine wheel selection.
Would love to see some data on this. Doughtful that anyone who has done the PITA work to get this info would share. Anyone?
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Originally posted by toddstacky
Craig, Is SpeedGallery a Board Sponsor?
I don't want to promote a non Board Sponsor Craig.
Craig, Is SpeedGallery a Board Sponsor?
I don't want to promote a non Board Sponsor Craig.
Craig
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Chad/Anyone else who cares, I have some decent reading that's posted on the net about reading compressor maps.
http://www.turbosaturns.net/articles/articles.htm
Deciphering compressor maps part 1 and 2 are good but you might want to read others for fun as well.
I assumed Alex has GT35's but they're actually hybrid since they swapped to the K24 I believe exhaust housing and I'm not sure how that changes the map compared to the standard Garrett housing but it SHOULDN'T be dramatically different. His turbos won't run out of breath at 5,500 rpms unless he's trying to run some insane pressure level like over 3 bar.
http://www.turbosaturns.net/articles/articles.htm
Deciphering compressor maps part 1 and 2 are good but you might want to read others for fun as well.
I assumed Alex has GT35's but they're actually hybrid since they swapped to the K24 I believe exhaust housing and I'm not sure how that changes the map compared to the standard Garrett housing but it SHOULDN'T be dramatically different. His turbos won't run out of breath at 5,500 rpms unless he's trying to run some insane pressure level like over 3 bar.
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