Intercoolers...997,2 Vs 997,1...Game over...

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Nov 15, 2010 | 03:23 PM
  #16  
Quote: Skand', do you feel the car stronger? or not perceptible?

For the flow, a boost datalog would help yes I think...
I believe a boost datalog would have to include a pre and post IC sensor...something that most enthusiasts are unable to do readily (Durametric only measures at the Y pipe.)

I bring up the chart only to stimulate discussion and render opinions from others...the chart appears to demonstrate a 10% drop in flow at just 2 psi. It would be interesting to see what would happen at peak boost levels.
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Nov 15, 2010 | 03:34 PM
  #17  
Quote: I believe a boost datalog would have to include a pre and post IC sensor...something that most enthusiasts are unable to do readily (Durametric only measures at the Y pipe.)

I bring up the chart only to stimulate discussion and render opinions from others...the chart appears to demonstrate a 10% drop in flow at just 2 psi. It would be interesting to see what would happen at peak boost levels.
It requires a 2 psi pressure differential to move x cfm across the core -*do not* take that to mean you're losing 10% flow at 2psi and will lose at ton more at xx psi. For the average 997, you'll probably move ~450 cfm across a single core. The losses are generally linear so you're going to lose 3-4 psi across the core with ANY of these coolers at representative flow levels. The difference in pressure drop required (i.e. the extra work the compressor will have to do) to bring the .2 coolers in line with the 3.5" Bell core (gray bar) or .1 cooler at representative flow rates in the 500-600hp range is going to be around 0.5-1psi -hardly anything for the massive ~15% boost in thermal efficiency.
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Nov 15, 2010 | 03:35 PM
  #18  
Also i ve logged two more sets of aftermarket ICs...But I wont post results...I respect that both companies acted proffesional and refunded them...
My car has APR tune,which presses stock VTGs to their limits...The most difficult job of an IC is to be able to cool properly a small turbo that is pressed hard and tends to heat more...Larger turbos have better efficiency and so they dont heat up as much the air...
On the other hand a small decrease in air flow wont hurt...we have to see it as a total,a little less flow BUT much less air temp=more dense air...so less volume of air is needed to bring the same o2...
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Nov 15, 2010 | 03:59 PM
  #19  
time diff from 100-240km between runs is 0,45sec...also on 997,2 run fuel was 3/4 while on 997,1 it was 1/4...car did 6,1 100-200 with 2 persons of 110kg each and 3/4 fuel on a flat surface...which is good i think...
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Nov 15, 2010 | 05:59 PM
  #20  
Quote: It requires a 2 psi pressure differential to move x cfm across the core -*do not* take that to mean you're losing 10% flow at 2psi and will lose at ton more at xx psi.
Earl...the graph shows what it shows...at 2psi, there is a 10% reduction in flow when you compare the two ICs. I never stated any other relationship.

Quote:
The difference in pressure drop required (i.e. the extra work the compressor will have to do) to bring the .2 coolers in line with the 3.5" Bell core (gray bar) or .1 cooler at representative flow rates in the 500-600hp range is going to be around 0.5-1psi. -hardly anything for the massive ~15% boost in thermal efficiency.
15% boost in thermal efficiency...I don't see sensor readings to calculate thermal efficiency in the posted data set. The measurement requires both the inlet, outlet, and ambient temperatures to calculate the ratio.

While I do think this is a very cost effective upgrade, I do not have enough data to call this a "game over" solution.
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Nov 15, 2010 | 06:02 PM
  #21  
On another note, Skandalis, did you need to modify anything to accommodate the newer intercoolers as Earl did for the 996TT?
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Nov 15, 2010 | 06:06 PM
  #22  
Bob,ambient and output temp are logged...however in order to have inlet temps,more equipment is needed...By observing data i realised that as speed increases performance gets better...I was scared to reach 300km with such tires...(you have to see them...)By friday I will have new ones and so high speed runs will be logged...
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Nov 15, 2010 | 06:08 PM
  #23  
Quote: On another note, Skandalis, did you need to modify anything to accommodate the newer intercoolers as Earl did for the 996TT?
IC ducts needed minor trimming...GT2RS ICs are thicker...Everything else is bolt on...
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Nov 15, 2010 | 06:11 PM
  #24  
Quote: Bob,ambient and output temp are logged...however in order to have inlet temps,more equipment is needed...By observing data i realised that as speed increases performance gets better...I was scared to reach 300km with such tires...(you have to see them...)By friday I will have new ones and so high speed runs will be logged...
You (and Earl and others) have done a very good job logging data for comparison. Thank you.
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Nov 15, 2010 | 06:22 PM
  #25  
My pleasure Bob...Today i switched back to Remus exhaust for 997,2 ICs run in order to compare them with the same exhaust as 997,1 ICs...that way the only difference is the ICs...tomorrow i will switch to catless speedtech exhaust and observe differences...stay tuned,more logs and runs are about to come...
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Nov 15, 2010 | 06:40 PM
  #26  
So what brand ic's did you settle on? Is madsex following suit with his ic's?

Im guessing the 100 to 200 thread will see some shaking very soon heh?
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Nov 15, 2010 | 06:46 PM
  #27  
Quote: So what brand ic's did you settle on? Is madsex following suit with his ic's?

Im guessing the 100 to 200 thread will see some shaking very soon heh?
hes running 997.2 or gt2rs intercoolers OEM Porsche brand
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Nov 15, 2010 | 06:48 PM
  #28  
Quote: Earl...the graph shows what it shows...at 2psi, there is a 10% reduction in flow when you compare the two ICs. I never stated any other relationship.
this threw me off (particularly the "just"):
Quote:
the chart appears to demonstrate a 10% drop in flow at just 2 psi. It would be interesting to see what would happen at peak boost levels.
flow at a given pressure drop has nothing to do with what boost pressure the car is running, its just a way of measuring. At 2 psi of pressure DROP, the core flowed 10% less, not a big deal. You can easily recover this by commanding the compressor to turn a wee bit faster -and this is exactly what the wastegates will do since the MAP sensor is referencing boost post-intercooler. The downside is slightly more heat from the compressor, which is obviously being quelled by this IC. I just want to be sure people aren't interpreting the chart as "OMG you're going to lose 10% of flow and, in turn, power from engine, and thats at only 2 psi! it'll surely get worse a boost goes up" -that's not the case at all here. I would encourage folks to read up on flow benches if there's some confusion. I can't stress enough how much we're in the weeds here with regards to flow differences across all 4 ICs in the chart.

Quote:

15% boost in thermal efficiency...I don't see sensor readings to calculate thermal efficiency in the posted data set. The measurement requires both the inlet, outlet, and ambient temperatures to calculate the ratio.
FWIW, I logged compressor outlet temps on my setup, stock .1s were ~65% and still plummeting, .2 were around 80% and stabilizing

Edit: Don't get me wrong, there are better intercooler options out there, but there are also many that do worse at 2-3x the price.
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Nov 15, 2010 | 07:11 PM
  #29  
Quote: hes running 997.2 or gt2rs intercoolers OEM Porsche brand
Hmmm...interesting. So Skand how did you manage getting all those different brand ICs without having to part with the hard earned? Most new parts places dont take stuff back once its been used.
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Nov 15, 2010 | 11:15 PM
  #30  
2 psi?? Who cares what's happening at 2 psi? You can fart greater than 2 psi.

It seems like the data was cherry picked to show the greatest difference. Whether it's meaningful is a completely different story. Clearly the 997.1 ICs are crap and the 997.2 are signigicantly better at least for the 620 hp range as shown by Earl and now Skand. What if you want 800 hp? Will the 997.2 still hold up? Or does one shop around for other options? Since there is not much data out there, it's anyone's guess at to which IC is the best and for what application.
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