cg303

Can someone tell me if having a large intercooler has a disadvantage in the sense that theres a greater risk of boost 'lag' as the air will probably take longer to work its way through the intercooler or is that one of those turbo myths that have no warrant when boosting a car?

majik

Seems to make sense for me. I believe it's true. The larger pipes and i/c require more air to fill up and to reach the same amount of pressure.



Blow into a 1" hose and then blow into a coffee stirrer. One takes more pressure than the other. Your turbo is only pushing a limited amount of pressure - now blow through the stirrer straw into the regular straw - the limitations of the turbo are represented in the stirrer straw, as it would take much more pressure to fill up the regular straw with air and your turbo may not be big enough to do so. Upgrade to a bigger stirrer straw (turbo) to get more air flow and pressure through the regular straw (intercooler).



- I know very little about turbo systems, I just wrote that based on common sense. Feel free to correct me -

turbosocks

there will be more lag, how significant will depend on the size of the cooler.. you should always get a cooler thats appropriately sized (i'd go a bit bigger) to what you are wanting to do with it.



below are just really rough examples but you can get the pic...



say a 250ci intercooler is efficient at cooling 2X of air and spools @ 2000rpm.



if you have 2.5X or air, it will still spool very quick, but the air will be hotter, thus less power.





if you have a 700ci intercooler that can cool 10X of air with only 2X of air going through it, the air will be cool but with the upped volume of the IC, increase the lag.





taking lag only into consideration and not the thermal efficiency its pretty simple... a large room takes longer to fill with air than say a small bathroom, no matter the source and/or pressure of the air.

koreancorvette01

I agree with you guys as far as lag goes , however same example large straw to small straw, large straw takes longer to fill up but the amount of measured air in the straw is more at the same pressure then a smaller straw air volume, both have the same pressure . I have been curious as to what there would be to gain from running bigger piping and a larger intercooler. Again you will add lag but more air volume at the same PSI should result in more power at a lower psi. My theory anyhow.