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the way I was always told to pick a intake was that dual plane are for lower RPM power and single plane was for higher RPM power.
one of the things you also have to work with is if it is an auto or manual. if it is an auto then you will want to go for more lower RPM power so you don't have to change the converter on the tranny. with a manual it really makes no difference because you pick when to shift.
bottom line, if you look threw all the power gain RPM's on what you are buying this will give you a pretty good guide. but just like I did...if you have any questions post up. rumblefish360 helped me quite a bit when I chose what to buy and mine is probably going to be on the road this week.
I got my aluminum intake from summit for $169 to my door. cam/lifters/timing chain was $279.00 from ebay and that set was new(260H). thiming chain tensioner was $35 from mancini racing. then I had the typical gaskets, fluids and hoses from autozone and it cost me $100 to mill my heads down .010 and clean them. that brought my compression up over 9:1. oh, and a new oil pump for some cheap insurence. I already had the 4bbl holley with vacume secondaries and had already put better plug wires, coil, and recurved the distributor so I am just about done with the motor for now anyway....