Head Cam combo

[jonnyk]

Converting backwards from the J4J1 to an A9L wouldn't be easily achieved since the electric fans are driven by the computer also. Look towards a custom chip burnt for your combo, or if you feel like doing a lot of learning and reading, an EEC Tuner or TwEECer.
I would recommend a set of AFR 165cc heads or Twisted Wedges also, the TFS really can't be beat for the money. Both make great power and the AFR's also have a nitrous/blower exhaust port option so that takes away a lot of the TFS advantage with a power adder, if you get this upgrade.
Your ported Cobra intake will flow great and match up nicely to aftermarket heads, and IMHO will NOT limit your power capability at all. It may be limiting on your RPM range, but most street setups rarely spin past 6000 revs.
TFS makes excellent cams to match their heads, which a lot of people I know have been using with the AFR's with good success as well. Comp Cams makes a more aggressive off the shelf cam, but they cost almost as much as a custom cam (which you might consider if you're sure on what you will be doing with the car). My $0.02..