Which intake manifold for an E cam 306?

[9A Pilot]

The car is a full weight 92 LX hatch..
Heads are 58 cc AFR 165's.
It made good power to 5300...then nosed over pretty bad on the dyno graph.
It's got good driveability..No issues..
Walbro 255 pump with 24lb injectors.
It made 283 rwhp/328 tq

Shorty headers /Off road H/Flowmaster 2 chambers

The current manifold is an UNPORTED FRPP GT-40..
Keeping this manifold appeals to me..I think its a cool looking unit.
But the heads seem to want more than what it can give..
Is it worth porting ?
Or should I ditch it for something better.
Please limit the discussion to the manifold..Because the E cam/FRPP 1.7s stay put.

 

[bigwill306]

i voted for the rpm II, but i have used a TFS street heat and loved it. but not even similar to your set-up. i have seen ported gt-40's on limited street cars and they ran crazy numbers. some of the Pro. Products intakes are good, just have to take the flash off them. they are chaep and work well. might also be chaper to just work with what you got, depands on what you get charged to port the intake you got.