but back to what moehler said aboutt he boost response...

there's so much air moving through those pipes so fast that you're going to have to show me some serious evidence there's any NOTICABLE boost response differences... milliseconds don't count.

 

anybody with ARC products

 

anybody

 

I have seen many of the Japanese Super Taikyu and even some JGTC) cars running ARC radiators and oil coolers, but very few with ARC intercoolers - and most FDs with a V-Mount of sorts. Lots of the hard core endurance cars usee the ARC trans and diff coolers too. I've seen a lot of the ARC products first hand and they are top quality, but unfortunately - no hard data on the IC's

 

Do a back-to-back test of the stock IC and any large aftermarket IC (SM or FM). Drive the car, swap the IC, and drive it again. The difference in boosty-throttley-response is quite noticable. I discovered this after swapping my stock IC in to replace my ASP Medium IC for a SMOG test. The ASP Medium has about the best ratio of increased core size versus increased overall piping and IC volume possible (i.e. this is a best case scenario; big core, short pipes), so it's got to be worse with other ICs. I wish this wasn't true, but in my experience it is. Of course, even knowing that I had a FMIC made that has a significant amount of wasted volume.

-Max

 

The issue with the IAT/AIT (intake air temp; I don't care which acronym we use) is that the UIM and AIT sensor heat soaks. If you have a FMIC that hasn't heat soaked, you will get a big rush of cool air when you start moving and get on it. The actual intake air will be pretty cool, but the heat-soaked sensor (or maybe it's the heat-soaked UIM that is really the problem) will read much warmer than the air actually is. This could be dangerous since more oxygen molecules are entering the engine than the computer thinks there are. You might run lean as a result. This discrepancy is probably less of a problem with a SMIC, since both the IC and the manifold/sensor will be heat soaked.

I notice that the IAT heat soaks even when driving. I am almost sure my sensor reads hotter than the air really is a lot of the time. I can hop out of my car and feel that the IC out pipe is cool to the touch, and yet the IAT sensor will be reading 38C or something like that with the car moving.

I wish there was a good way to increase the accuracy of the IAT sensor, but I haven't heard any overwhelmingly positive results with relocating it to the elbow, etc. It does seem like it must be better to get it into something that is lower mass (and less likely to heat soak), but I'm not sure just how well that works. Perhaps some thermal barrier stuff (like aluminized hot water heater blanket stuff, for instance) to cover the bottom of the UIM would help. And some LIM and UIM gaskets that don't transfer heat as well as the stock ones might help, too. I know some people were looking at some alternate sensors for a while, but I am not sure how that worked out. If someone does have positive results with some solution, please share it.

-Max

 

put the iat in a rubber hose.