i would say put the e-cam in. it shouldn't really hurt u. it won't work as good cause of the stock heads, but u said there ported so that might make a difference. i have a e-cam with stock un-ported heads, and have noticed more power above 3000 rpms. i also did a lot of other work to the motor at the same time, so it could have been from other things too. i went with the cam cause i plan on puttin on a good set of heads soon and since the engine was out it was a lot easier to do it then as compaired to later with the engine in and such. good luck
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89 GT AOD w/ shift kit, B&M rachet shifter, Trickflow intake, Crane (E-type) cam, 70Tb, 75MAF, 1.6 Rockers, Pulleys, MAC headers and H-pipe, Dynomax mufflers, K&N, 3 core radiator, white face gauges, custom interior, cobra R rims. 14.9 at 95.07mph with stock 2.73's.
89LX 2.3 Notch, daily beater!
MY89GT