BT: is it worth it to replace APR DPs?
03-18-2007, 02:34 PM
#11
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Thats a little misleading Mark. My car will zing to 1.7B after a fillup/Trim-erase at ~3200rpms and
I have LaBrees. N75 duty cycle has to be relearned each time the trims are reset.
On a flakey N75 it would do it at will, thought my boost gauge was the culprit last year... there is no ramp issue I've found on these DPs yet, running K04s of course. Maybe the MTM thing is a coding trait... not advertizing for anyone, just stating what I've seen and observed.
On a flakey N75 it would do it at will, thought my boost gauge was the culprit last year... there is no ramp issue I've found on these DPs yet, running K04s of course. Maybe the MTM thing is a coding trait... not advertizing for anyone, just stating what I've seen and observed.
03-18-2007, 04:23 PM
#12
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All I am saying is that same code, ASP DP vs. Other DP's will..
100% percent yield a diff ramp up and peak curve.
Clearing Memory Fault does not affect N75 Maps. N75 duty is not learned it's programmed.
Clearing Memory Fault does not affect N75 Maps. N75 duty is not learned it's programmed.
03-18-2007, 05:19 PM
#15
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Sent it last Tues. to info@autospeedperformance.com
I believe you meant to say less of a pressure drop.
Your website doesn't specify that this occurrence is just with K04's, you might want to clarify that point so people with K03's aren't misled into thinking they're going to see the same improvements.
Your website doesn't specify that this occurrence is just with K04's, you might want to clarify that point so people with K03's aren't misled into thinking they're going to see the same improvements.
03-18-2007, 05:29 PM
#16
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So how much more HP are your DP's going to make compared to the 'others'? If
there's that much of a difference in pressure loss at less than 100 g/s of airflow, the pressure loss difference will be approximately 10x as great at 350 g/s. One would think that much of a difference would produce some substantial HP gains versus the 'others'.
I'd like to see some real numbers to prove the DP's are that much better, because it's a bit of a stretch to think they make that much difference compared to the alternatives that are available.
I'd like to see some real numbers to prove the DP's are that much better, because it's a bit of a stretch to think they make that much difference compared to the alternatives that are available.
03-19-2007, 09:05 AM
#18
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Since I'm pinging on your DP claims, about that engineering
you're using to explain why they work better on the web page.
<i>2.) Use larger tubing to gain volume carrying capacity by lowering air pressure. Remember air is compressible, if we can make the air less dense, than it becomes lighter. The lighter it becomes the faster it moves.</i>
<i>3.) Use a material that has a low thermal transfer coefficient so that heat is retained in the tubing.
The hotter the air, the lighter it is. The lighter it is, the faster it can move.</i>
Sketchy stuff.
<i>2.) Use larger tubing to gain volume carrying capacity by lowering air pressure. Remember air is compressible, if we can make the air less dense, than it becomes lighter. The lighter it becomes the faster it moves.</i>
<i>3.) Use a material that has a low thermal transfer coefficient so that heat is retained in the tubing.
The hotter the air, the lighter it is. The lighter it is, the faster it can move.</i>
Sketchy stuff.
03-19-2007, 12:54 PM
#20
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Well, regarding the first quote,
<i> 2.) Use larger tubing to gain volume carrying capacity by lowering air pressure.</i>
When the exhaust gasses exit the turbo and enter the larger area of the DP the velocity will slow and pressure will rise.
<i>Remember air is compressible, if we can make the air less dense, than it becomes lighter. The lighter it becomes the faster it moves.</i>
If you make the air less dense, it is because you are increasing the volume. If the air travels through a fixed volume like the exhaust system and the volume of the air is increased, the velocity of the air exiting the system may increase, but the mass flow rate remains the same, so the same quantity of gasses are leaving the pipe either way. But pressure drop from friction and minor losses increase with the gas velocity. Low density air is good, but calling it lighter is not an accurate statement without qualifying if you're referring to the mass occupying a specific volume.
<i> 3.) Use a material that has a low thermal transfer coefficient so that heat is retained in the tubing.
The hotter the air, the lighter it is. The lighter it is, the faster it can move.</i>
For a given number of molecules of air, how hot they are doesn't change their mass. This is getting back to air density. Less dense air will decrease pressure losses, but the impact of temperature on density and the subesquent pressure losses isn't dramtic over the temperature ranges the exhaust gasses cover.
When the exhaust gasses exit the turbo and enter the larger area of the DP the velocity will slow and pressure will rise.
<i>Remember air is compressible, if we can make the air less dense, than it becomes lighter. The lighter it becomes the faster it moves.</i>
If you make the air less dense, it is because you are increasing the volume. If the air travels through a fixed volume like the exhaust system and the volume of the air is increased, the velocity of the air exiting the system may increase, but the mass flow rate remains the same, so the same quantity of gasses are leaving the pipe either way. But pressure drop from friction and minor losses increase with the gas velocity. Low density air is good, but calling it lighter is not an accurate statement without qualifying if you're referring to the mass occupying a specific volume.
<i> 3.) Use a material that has a low thermal transfer coefficient so that heat is retained in the tubing.
The hotter the air, the lighter it is. The lighter it is, the faster it can move.</i>
For a given number of molecules of air, how hot they are doesn't change their mass. This is getting back to air density. Less dense air will decrease pressure losses, but the impact of temperature on density and the subesquent pressure losses isn't dramtic over the temperature ranges the exhaust gasses cover.