What I wrote last for some reason didn't post, so I'll just do a bullet version.
·600 hp or power to weight ratio of 6 or less.
·A Tremec 5-spd will not hold up to this much hp. I couldn’t get the
tranny to go into the next gear unless I got out of the throttle. Try T56 6-spd
·Custom drive shaft
·3.73’s to tall, will probably need 4.30’s to 4.56’s
·13.5 or higher compression, (No av gas, because it will typically eat up the O2 sensors within a 100 miles. Try E85 with its 105 octane rating
·Bullet proof bottom end
·Remove as much weight as possible from the
stang, such as fiber glass hood, etc.
·Port and polished heads as well as intake
·High lift roller cam either hydraulic or mechanical. Most cam manufacturers will suggest a grind based on your setup.
·Customer ECM, such as Hypertech
·9” rearend
I also suggest that you go with a stroked 351. They have a lot more torque, which would provide faster launches as long as the power gets to the ground. Go to
http://www.race-cars.net, and select et calculator, which also have other variations. Hope this helps.
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‘88 LX Hatchback: 351 stroked to 408 w/4 bolt mains & steel crank, 12.5 :1 forged pistons, Cartech “Bread Box” upper/Edelbrock lower(ported and polished), BBK 75 mm Mass Air w/120 lb injectors, Dart II ported, polished O-ringed 2.02/1.60 heads, Custom Competition Cam hydraulic roller w/Roads lifters, Hypertech custom chip, 1100 hp Aeromotive Competition fuel kit, 9” w/ 4.86’s, Tremec T56 six speed, , Hotchkis performance suspension, 400 shot of nitrous. Passes emissions running E85.
what will it take to run 10.50s 
I'm not familiar with the heads but to run 10.50 they'll need to be a good set with a fairly radical cam. Larger injectors are a must as well as a larger TB and mass air. I don't know how much more you'll need to do to get to that time, but probably more than that.
