Nearly three years ago, it was believed that excessively large inter coolers would actually hurt performance (more lag etc.)

However real world experience seems to strongly support the claim that bigger is better.

For example, at one time it was thought that 3.5 inchers would be perfect for a set up like my car (3076s, fuel system, etc.) Now, according to experts, a say massive 5 incher creates better ambient flow, decreases the pressure drop through the core, and of course has better temperature drop.

Please discuss.

 

i beleive thats true with high HP applications, big turbos lots of air flow.would make no sence to have monster coolers on a k24 car.

 

For an exact comparison, all variables accept for core size would be held constant. However, this doesn't make much sense to do or apply except within a narrow performance range. Sort of like the exhaust size/back pressure issue. It's probably more useful to decide which is better depending on intended use.

new to 996tts but in past experiences, smaller coolers are only "better" in the cases where the car is driven only in the street or autoX, where the value gained in response is greater than value gained in cooling.

 

The thing is, 3 years ago when people were extrapolating based upon mathematical hypothesis, everyone said bigger coolers cause lag, but the real world has proven different, bigger coolers on moderately large turbos (GT 30's, 24/20s) give significant performance increases.

 

I have heard by a reputable source that even with the 24/18's the 5" coolers will help with air flow & be less restrictive. I have been told that each deg. less of intake temp = ~ 1 HP more.

 

Without real world comparison testing this is all moot. We hear all this about one IC better than another, but until we see the same car running back to back with different IC's, it is all moot. There is a good chance that a thicker IC, prevents airflow through it and makes things worse. I see good tests for individual IC's but I don't see actual comparisons. We need Testing compared.

I would love to see comparative testing. Heck, IMO secan should sponsor the testing.

 

The only way to prove or disprove this would be to test all of the different setups. Pressure and temperature sensors would need to be mounted before and after the intercooler inlets and outlets measuring air temperature differences. There are so many other variables that in order to gain definitive information, the tests would have to be conducted in a controlled laboratory environment.

A thicker core is not always better. Thicker cores can have a difficult time dissipating heat especially if there is not an adequate amount of air passing through the core to cool it. Air ducting is extremely important and the air volume / velocity passing through the core can dramatically impact any size intercooler efficiency.

 

The question is how high does the intake temps reach & at what temp does it have effect on the HP? Put it simply what IAT is acceptable & what IAT is detrimental?

 

So what thickness do you think is the best for the 24/18 set-up and do you think a thicker core will hurt performance?

 

With a big blow through air intake system and Gt 30 and bigger turbos there is no doubt that the larger IC's are advantageous. But yes, I would like to see a direct befors and after comparo. The prob is, I am installing my new intake and it custom fits my IC's, there is no way to directly compare w/ the 3.5 inchers. My car ran a 5.79 w/ my somewhat restrictive intake and 3.5ers it had better run faster w/ my new set up.

 

how do you know that your scargo intake was restrictive? now you are adding IC's into the equation. How do you know which one is what gave you the better performance?

 

I am speculating, we can't really run the test until all is done....and 8 grand is spent

 

But look at the crazy 700 whp plus SPI/Proto/Mark-Bobby stock block cars...all are running full proto style intake and huge IC's

The anecdotal evidence is hard to refute. I remember when I ran my GT 30's everyone was waiting for my motor to blow so just call me Gin E Pig.

 

by significant performance increase, do you mean response or power? An interesting real world test would be to compare circuit lap/drag/trap times, changing only the cooler.

 

5" intercooler are old news! 6+ is the only way to go! jk