I have a 1986 Chevy Monte Carlo SS t-top.The 305 orignal is just to tired and weak.With well over 400,000 miles.I want a motor to put out 450 to 500hp and also drive on the street.Can I do it with the computer still installed?If not what can I build.350 or 383 I saw the article with the new AFR 195 heads.Can I get it on a little cheaper budget?Are there any other heads I can use.I want to keep the air conditioner on, and will the 200r transmission hold up to that kind of power.I want to put a 12 bolt in it will one off a chevelle bolt right in? I'm not worried about gas mileage if I use the 12 bolt I want to use some 4.33 gears.About 10.1 compression.I love the 383 I call it a big block killer.Should I go with a th350 transmission.Please help me out.  

(I want a motor to put out 450 to 500hp and also drive on the street.)
No problem...
(Can I do it with the computer still installed?)
No...not with that ECM
(If not what can I build,350 or 383)
The 383 is the better choice for your goal of 450-500hp
(I saw the article with the new AFR 195 heads.)
Me too, nice heads...great choice for a street-driven 383 or pro-street 350.
(Can I get it on a little cheaper budget?Are there any other heads I can use.)
Dart Iron Eagle.
(I want to keep the air conditioner on,)
I don't blame ya.
(and will the 200r transmission hold up to that kind of power.)
Uh...no
(I want to put a 12 bolt in it, will one off a chevelle bolt right in?)
Uh...no, it's not a bolt-in and the 9" Ford is a better choice IMHO
(About 10.1 compression.)
Your gonna want Aluminum heads with that CR to run pump-gas
(I love the 383 I call it a big block killer.)
Cool, I love the ZZ427, i call it the small-block killer.
(Should I go with a th350 transmission.Please help me out.)
TH350 built right will do fine.
There's several different paths that all lead to a 383 stroker, i prefer a long-rod (6.0") motor with a hydraulic-roller and 200cc intake runners, set the rev-limiter at 5,500 and let er eat.  

Thank you! I really appreciate it.Everything you told me I will use.Are the Lunati vodoo cams work just fine or a comp cams.Also I have a 1969 Chevy Nova with a 383ci all drag.I have killed plenty of big blocks 468s on motor or the juice.Thanks! I will let you know how everything turns out.  

gm performance parts 383 short block,a pair of new bowtie vortec heads,comp cams hydraulic roller (520,540,236 242 @.050)performer rpm intake 750 demon=approx 460 hp and almost 500 ft lbs of torque on pump gas with only 9.7:1 compression.freind has this combo in a 86 monte,with a 2800 stall,373 gear,200r4 tranny,runs low 12's with the air conditioning on.