05 OTR on 04 GTO
 

What's the difference that an 05 Vararam OTR intake won't work on a 04 GTO? Can it work?

The Vararam is not an OTR CAI, it works with the 05/06 hood scoops. 04 radiator is different as is the radiator cover

I picked up a 05 Radiator and overflow tank. I already have the 05 hood installed on my car. The guy was gonna give me his radiator cover too since he doesn't need it. Will it work with all that? Is the Vararam more like a ram air intake then too?

All of that will work on an 04, I have an 05/06 radiator, overflow tank and cover on my 04.
Don't know how much ram air effect is, but it should help at higher speeds.

Get an X-air or find a used svede they will hands down outperform the Vararam and help keep IAT's a little cooler.

The vararam is shoddy built. the other two mentioned are built much nicer. The x air is the one i had. my buddy has a vararam. I had two different vararams on my 5th gen camaro. In my humble opinion, they are built like shit. The plastic is cheesy. the bolt holes strip easy. the thread inserts come out. the air filter didnt seal well. But its your money.