I'm swapping heads to vortecs but not sure what manifold will suit my set up, everyone is saying RPM air gap but I don't spin my motor over 5500 so I'm not convinced. I was swaying towards performer again.


Current set up
355 9.2 to 1CR
Cam
Intake Duration at 050 inch Lift: 214
Exhaust Duration at 050 inch Lift: 214
Valve Lift with Factory Rocker Arm Ratio: 0.442 int./0.442 exh. lift
882 heads
edelbrock performer intake
600CFM carb

Stock hood? Clearance? Those intakes get some taller than the Performer and stock intakes. .

I've got a stock hood and 3" cowl hood so clearance shouldn't be an issue.

You are fine with a Performer. That's where I'd lean towards as well.

Look into the Performer EPS Vortec. It's the updated version of the old Performer but with computer modeled runners and such- technology borrowed from the RPM line. It's optimized for the idle-5500 RPM range. Look here about 1/3 way down the page at part number 2716:

http://www.edelbrock.com/automotive_new/mc/manifolds/chevy/performer-sb.shtml

Weiand also has a new line of idle-5500 intakes with similar computer-optimized runners and such. Here's a link to the version that is designed for Vortec heads:

http://www.holley.com/8121.asp

What ever intake you decide on, get one designed specificallu for VORTEC heads.