Well, I spent most of early this morning researching this very topic. I'm trying to decide which intake to go with, as well.
I must say this first: if all you're planning on doing is changing the intakes, you won't see squat for a power increase. Maybe 5hp if the Ford gods are generous.
On the TrickFlow street, they're designed to reinforce your low end torque more than others (read: long runners, good airflow distribution). I've heard a lot of complaints about them up top, though. If you stick with the stock cam, you'll never know the true 'top end' anyway.
Depending on what mods you make in the
future should influence your choice. The GT-40 and Cobra flow nearly identical numbers (gee, they use the same lower, wonder why?), but at least you can extrude hone and/or port the Cobra later. Plus the Cobra will stand a nitrous backfire a little better. I'm going with the Cobra or mebbe the Edelbrock, but it's up to you.
Spend your $$$ is better places, that's my recommendation. Gears & Mass Air conversion: you can't go wrong. Good luck.
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Capri306, Moderator, The Mustang Works Online
1979 Mercury Capri, 5.0L -- C4 -- 2.73
1987 Mustang LX Notch 
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