The Indy EZ's will raise the intake slightly higher than the stock heads due to their design. The Shaker still works on my '70 E-Body though. It is snug though.

Those old sixpack intakes surprise a lot of people with how well they can be made to work. The 493" motor I was running dynoed at 684hp below 5500 RPM. There's a write up on it on Hughes website. It's all about the combination. That was with a hydraulic roller. I dropped the compression 2 points and am converting to a slightly larger solid roller cam. The motor won't get on an engine dyno, but I'll eventually run it on a chassis dyno one of these days.

I've since learned that even ported sixpack intakes do significantly hinder the flow of my ported Indy EZ's, which flow around 345cfm at .600 lift. I had Hughes port my intake to the limit of their current knowledge, but they are digging deeper into them to find more flow as of this writing. This could get interesting real soon.

I'm going to installing a set of 3 modified 2300 series mechanical secondary carbs (the old Direct Connection Mechanical secondary Race carbs) that flow more than they did stock. Just how much more I won't know for a few weeks. The center 350cfm carb is being replaced with a 500CFM outboard mechanical carb, which didn't have idle circuits in them stock. This is being addressed so it can be used as a center carb. The boosters and barrels are being removed and the carbs are being converted to aerosol booster style by C&S Specialties. They build a lot of race two barrels for the roundy round guys.