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Well, considering no one on LS1Tech wanted to give me any advice on my idea, I went ahead and did my 85/85 intake mod. I recently purchased a 78MM fast from a friend for a really good price but as everyone knows, a 90/90 is better. I don't know about most people here, but I am on a tight budget and $1100 for an intake and throttle body is a bit much. My solution? I bought a polished 85MM Professional Products TB from Byunspeed for $185 shipped. At first I was going to use the adapter plate that came with it, but I realized it would be pointless considering the intake opening was only 78MM and would restrict flow. I then took a set of calipers and measured the FAST intake to find that the inside diameter of the outer O-ring retaining rib was approximately 85MM. I was concerned about sealing the TB to the intake at first, but lucky for me, the 85MM TB comes with a nice gasket to seal the TB to the adapter plate I was not going to be using. It would work perfect to seal the TB to the ported intake. So I started grinding. Took me about 4 hours to actually get it completely shaped right using a carbide burr - I found that sanding drums just melted the plastic and didn't provide a good finish. It came out nicely and I'll have 99% of the performance of a 90/90 for about half the price. I also ported the TB while I had the time, so it should flow pretty close to a 90MM . What do you all think?
357ci LT1, cammed, stalled, and driven. 
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