Is it true OEM intercooler is better below 600bhp?

[narface]

Group A GT-Rs back in the days used the same stock intercoolers for racing. Group A BNR32 race cars were producing 600bhp, so the stock intercoolers are adequate.

[Bossman]

Is a question of velocity or better yet flow rate (Q=VA). I don't really have time to explain the science but this is the reason why there is variable valve timing and variable exhaust (AKA Ferrari). In short, if you are making less Hp then you want a smaller cross sectional area (smaller intercooler) to keep the velocity up (thus better response). Perhaps Frankiman can explain it to you.

[gezed]

How much power are you pushing? I guess its really hard to say if there is a loss or gain in response considering that people who run thicker intercoolers usually have bigger turbos as well

I think it is because the larger intercoolers cause too much of a pressure loss at lower power levels. That being said I run a 100mm thick Greddy intercooler and don't notice any significant pressure loss.

[Sharkus29]

I heard the stock intercooler is only recommended up to 400hp. But then again I could be wrong!

[Phastwon]

I think it is because the larger intercoolers cause too much of a pressure loss at lower power levels. That being said I run a 100mm thick Greddy intercooler and don't notice any significant pressure loss.

[gezed]

I saw this statement in the tyndago's website here:

https://sites.google.com/site/tyndago/rb26dett

is this because the flow of air at these power levels do not utilize the full surface area of a thicker intercooler?