What's The Right Cam???

I have a 91 Lx with a 5.0 and recent upgrades have been unported gt40 heads,typhoon upper/lower intake with 75mm throttle body and 76 mm c&l maf with matching tube. For exhaust I have bbk shorty headers bassani off road x pipe and full bassani "catback" and 3.73 gears. I have heard that a cam with my setup might not make to big of a difference and just to keep my stock cam, I've also heard great things about crane cams 2031 cam and not good things about "alphabet" cams.i want to squeeze as many ponies as I can out of it with out having to pull heads off and port them, someday I want aluminum heads and a turbo but this is what I have to work with. Any input on cam and what valve train?
 
If I were you, I would just put 1.7 roller rockers and run the stock cam. That'll bring your lift up even more than what it's at now and you'll get a nice little bump in power. Also, you'll need to get different valve springs for the GT40 heads if they came off an Explorer/Mountaineer. Those engines weren't ever intended to spin the RPM's our Mustangs do so the stock junk valve springs have to go unless you like valve float.
 
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I ran the Crane 2031 cam with the 1.7 Crane Cobra roller rockers for many years with a 306 and trick flow TW heads. It was a really nice combo; ran high 12's, low 13's on street tires leaving the line just above idle, and still got 20 mpg around town. I agree with the valve spring comment....
 
Either way you are going to need better springs. Summit sells the TFS upgrade springs for about $150, which I have on my explorer heads. There is nothing really bad about the stock cam and 1.7's. It will give you some decent lift but maintain good driveability for less money than a new cam install. A new set of RR may set you back 2-3 hundred or so. I see used ones all day long for 100-200.

You can do the spring install with the heads on the car- buy the air chuck attachment that screws into the spark plug hole with both valves closed and rent or buy the valve spring compressor tool to swap out the springs and retainers. Might as well replace the valve seals while your at it.

Back in the day when I was a kid we used to take an old rope and stuff it in the spark plug hole to keep the valves from dropping...lol dont laugh it worked but I wouldnt advise that method now.
 
I put a alphabet cam in my car e cam. To be honest it runs great makes power but could have gotten a lot more with a better cam choice. I have stock springs on stock heads and I float badly around 5k and up... Go with springs either way.
 
all the fast naturally aspirated cars run stock cams with 1.7 rockers.......



or not. if the right cam doesn't pick one up you have other issues. those who say larger than stock cams don't help should also subscribe to the hypothesis that aftermarket heads don't do anything either because increasing lobe area has the same effect as increasing port cross section.