What mods to get?!??

Hey all, I currently have the following mods, But I am wondering with 400$ what I should invest in? I was thinking maybe about a intake or pulleys, But maybe you guys think I should do traction stuff (traction bars, new differential, etc..) Let me know, and thanks in advance.
Also, Please include links to where I could buy the best version of your suggested item, if you are so kind :)

Mods:
New 308 bored block, 1.72 cran RR's, Competition cams 280, Forged rods and pistons, Hpipe, Flowmasters, K&N intake, Trick Flow Twisted wedge heads, Hooker long tube headers, Centerforce clutch, Metal quadrant, hurst Shifter, New top, HMrgasket engine set, 3:55 gears, Chrome valve covers, Alluminum driveshaft, Race Pro Aluminum Radiator
 
I would say the intake end of things needs attention but since you dont have enough for a good aftermarket intake and TB why not try something like a tmoss lower, then you should have enough left over for a larger tb.

edit:
I just realized your sig says "new top", do you have a convertable? $400 would probably be well spent stiffining up the chassis some or maybe even a roll bar if you can afford it.
 
Intake for sure - pm tmoss for more info. The verts are heavy too - do you have gears? That'd probably make the biggest difference. But the single biggest bottleneck to flow on the engine is the stock intake - who put the heads on with the stock intake? Guess they didn't know....
 
I'd get an intake on it if it were me - can't believe all the other mods were done, and it's all being strangled through the stock intake. Your claim of over 300 rwhp - you've had it dyno'd?

The convertibles are ESPECIALLY flexible in the unibody with the top cut off. Even though there are reinforcements, they're not nearly enough to stiffen up the unibody -- the subframe connectors will help with that. You gotta decide which you want next. I'd get the engine breathing correctly, then focus on tightening up the unibody.
 
The Typhoon is a good intake, but without changing heads it won't make much if any better average power in the 2k-5.5k rpm power band. Below 2k where we do lots of stop-and-go it's not even close - the stock or ported stock lower is the winner hands down. The aftermarket intakes offer advantages in power with better heads and at higher end of the usable rpm on a E7 head motor.