Maybe I can help as I've just been infusing a chair core which is a 7mm hit in one go (650 gms CF either side of several layers of quadaxial e-glass). Use a slow mesh and make sure you allow the resin to continue into the part for a while after it's reached the MTI hose. For me (on a 1.5 m2 360 degrees shape) the part wet's out in around 45 mins but isn't at a reasonable VF for a cosmetic part until about the 3 hour mark. This is with a very slow mesh/ silicone peel combination (Compoflex SB RF3). This seems to work every time now but the first time I was having issues like yourself.