I was kinda hoping you'd jump in on this AA, you always have good advice and ideas. I'll give you the story. I'm looking to put a cia in my 97 gtp which would require relocating my overflow bottle to fit. I have the option of switching to the 99+ factory bottle (very ugly) or going aftermarket. The 99+ bottle would mount on the passenger side strut tower and makes it more difficult to work on anything in that area (plus its damn ugly!). Most aftermarket offerings seem to be in the 18-24 oz range, which sounds tiny but may be big enough. The stocker is bigger than it has to be to give a safety margin. Those of us that check fluids regularly don't need as big a safety net but it still needs to meet a minimum size. I was looking at a weapon r catch can which is pretty, afordably priced, works in the factory vented style, has a sight glass, and has a fill cap, but the largest they offer is 24oz. I've seen others from canton at one qt, which is definitely big enough but may be more difficult to find space to mount. My intention was to mount it on the radiator support but there's no a huge amount of room. I will of course take measurements before buying anything but I was hoping someone might have some ideas or suggestions. Since the question was just general knowledge and not grand prix specific I thought I'd ask here, since many on the gp boards are know-it-all jerks. If I have to I will pull the bottle off my riv (both engines are l67's so it should be very similar I would think)and measure how much fluid it takes to go from cold fill to hot fill. Thanks in advance for any info. Oh and AA I just realized I'm not sure I posted this in the correct section, its hard to know where its gonna go from an old cell, so feel free to move as necessary.