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Just an FYI, the more pressure drop across the brick, the lower the IAT2’s will be.

So just because you get lower temps from one brick to another, you might not see more power.

Something to consider.


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By stating that there are other variables to quantify, I was
intentionally leaving out 'Pressure Drop' within my earlier
post as it is difficult to understand.

But since Steve / Karch is an expert on air flow
he of course opened up 'Pandora's Box'. .LOL

So I finished up my work for the day and decided to locate a good
article on Pressure Drop. I found one on the Buick GN site.

The thread on this site covers much more than Pressure Drop. . .
Here is the site => Intercooler Theory

Here is a cut and paste of the relevant info Steve mentioned.
While it deals with Turbo's, the applied physics are the same. . .

[TD]Pressure Drop[/TD]​
[TD]Another aspect of intercoolers to be considered is pressure drop. The pressure read by a boost gauge is the pressure in the intake manifold. It is not the same as the pressure that the turbocharger itself puts out. To get a fluid, such as air, to flow there must be a difference in pressure from one end to the other. Consider a straw that is sitting on the table. It doesn't having anything moving through it until you pick it up, stick it in your mouth, and change the pressure at one end (either by blowing or sucking). In the same way the turbo outlet pressure is higher than the intake manifold pressure, and will always be higher than the intake pressure, because there must be a pressure difference for the air to move.

The difference in pressure required for a given amount of air to move from turbo to intake manifold is an indication of the hydraulic restriction of the intercooler, the up pipe, and the throttle body. Let's say you are trying to move 255 gram/sec of air through a stock intercooler, up pipe, and throttle body and there is a 4 psi difference that is pushing it along (I'm just making up numbers here).

If your boost gauge reads 15 psi, that means the turbo is actually putting up 19 psi.

Now you buy a PT-70 and slap on some Champion heads. Now you are moving 450 gm/sec of air. At 15 psi boost in the intake manifold the turbo now has to put up 23 psi, because the pressure drop required to get the higher air flow is now 8 psi instead of the 4 that we had before.

More flow with the same equipment means higher pressure drop. So we put on a new front mount intercooler. It has a lower pressure drop, pressure drop is now 4 psi, so the turbo is putting up 19 psi again.[/TD]​

Cheers
 

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By stating that there are other variables to quantify, I was
intentionally leaving out 'Pressure Drop' within my earlier
post as it is difficult to understand.

But since Steve / Karch is an expert on air flow
he of course opened up 'Pandora's Box'. .LOL

So I finished up my work for the day and decided to locate a good
article on Pressure Drop. I found one on the Buick GN site.

The thread on this site covers much more than Pressure Drop. . .
Here is the site => Intercooler Theory

Here is a cut and paste of the relevant info Steve mentioned.
While it deals with Turbo's, the applied physics are the same. . .

[TD]Pressure Drop[/TD]​
[TD]Another aspect of intercoolers to be considered is pressure drop. The pressure read by a boost gauge is the pressure in the intake manifold. It is not the same as the pressure that the turbocharger itself puts out. To get a fluid, such as air, to flow there must be a difference in pressure from one end to the other. Consider a straw that is sitting on the table. It doesn't having anything moving through it until you pick it up, stick it in your mouth, and change the pressure at one end (either by blowing or sucking). In the same way the turbo outlet pressure is higher than the intake manifold pressure, and will always be higher than the intake pressure, because there must be a pressure difference for the air to move.

The difference in pressure required for a given amount of air to move from turbo to intake manifold is an indication of the hydraulic restriction of the intercooler, the up pipe, and the throttle body. Let's say you are trying to move 255 gram/sec of air through a stock intercooler, up pipe, and throttle body and there is a 4 psi difference that is pushing it along (I'm just making up numbers here).

If your boost gauge reads 15 psi, that means the turbo is actually putting up 19 psi.

Now you buy a PT-70 and slap on some Champion heads. Now you are moving 450 gm/sec of air. At 15 psi boost in the intake manifold the turbo now has to put up 23 psi, because the pressure drop required to get the higher air flow is now 8 psi instead of the 4 that we had before.

More flow with the same equipment means higher pressure drop. So we put on a new front mount intercooler. It has a lower pressure drop, pressure drop is now 4 psi, so the turbo is putting up 19 psi again.[/TD]​

Cheers
This is a noob question but Where is the stock boost pressure sensor in the LSA blower? It’s post intercooler right?
So we don’t know actual boost pressure the blower is putting out or pressure drop through the intercooler but we do know if the boost and temp going into the motor is so a decrease in IAT and increase in boost should mean increase in mass flow correct?


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This is a noob question but Where is the stock boost pressure sensor in the LSA blower? It’s post intercooler right?
So we don’t know actual boost pressure the blower is putting out or pressure drop through the intercooler but we do know if the boost and temp going into the motor is so a decrease in IAT and increase in boost should mean increase in mass flow correct?


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Subi,
Could you please rewrite that last paragraph, breaking it down with a
bit more detail so we can completely understand what you’re stating.

Thanks,
Bruce
 

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C&R brick in a ZL1 lid is what I would use on max effort CTSV/ZL1 builds
I'll probably go that direction then.
 
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FYI - I emailed C&R on their bricks to see if they had any data on IATs. Here's their response.

"We have got some recent studies. We are better than OEM. Temperature differentials are lower on average.
The CTS-V version of the LSA did perform better than the ZL1 but that is most likely due to lid design. Both were though, only marginally better than OEM.
The benefits of a lighter brick that is much stronger than the OEM is the main upgraded over OEM. Possibly opening up the water side some may work better but the test was also done using another company’s supercharger heat exchanger. Both paired together would yield better results.

Stock ZL1 Lid and Brick: IAT 2 Temp Differential Average was 44.66deg
Stock lid with PWR Brick: IAT 2 Temp Differential Average was 38.33deg

Stock CTS-V Lid and Brick: IAT 2 Temp Differential Average was 32.33deg
Stock CTS-V Lid and PWR Brick : IAT 2 Temp Differential Average was 29.66deg

Both lids and bricks were test on a 12 CTS-V, Stock bottom end, Ported Heads, Cam, headers, Pulleys. Car average boost is between 14-15psi."
 

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I feel like this is turning into another one of those "our testing showed a 20 HP increase with these new ignition coils!" kind of scenario... what the Old Timers used to call "too good to be true." :D

BUT, with that said, I'm glad that they have some testing to show it's better; I'd just like to know HOW they tested it. Average temps on a street car, dyno, steady state or quarter mile run?
 

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I feel like this is turning into another one of those "our testing showed a 20 HP increase with these new ignition coils!" kind of scenario... what the Old Timers used to call "too good to be true." :D

BUT, with that said, I'm glad that they have some testing to show it's better; I'd just like to know HOW they tested it. Average temps on a street car, dyno, steady state or quarter mile run?
2 different dyno pulls over a month apart in KY, where it does get cooler as Sept turns to Nov.. Dont see correction on the print out. But hey, better flow has to help, I don't doubt that.
 
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2 different dyno pulls over a month apart in KY, where it does get cooler as Sept turns to Nov.. Dont see correction on the print out. But hey, better flow has to help, I don't doubt that.
Oh yeah, good point - I actually know Nick Skaats (the dyno owner of that graph) and yeah... there's a bit of a weather difference between Sept and November in these parts. Usually 20-30 degrees depending on the day. This was actually the dyno that I first used when my numbers were really low on the AllPro build, so even accounting for the weather changes there's probably a decent gain (as Nick seems to take pride on having a "heartbreaker" dyno).

And I believe I know the shop when this dyno was done, it is... not temperature controlled. Think large metal building with no insulation and garage doors for entry/exit.

But if Matt says he's seen good results with them, I'd take that over a dyno print out any day.,
 
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