car craft had a 91 formula project car (350tpi) and they installed an slp intake, aftermarket runners and base, full exhaust (headers, cats, catback), torque converter, and 3.73 gears. they ran a low 14. with a 100 shot of juice it went a 12.9.
with a 305 u would have to do a lot to get it into the 13's. u would probably have to get 410 gears, a good converter, plus a ton of bolt ons and u may need to spray it.
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2000 Chevy Blazer ZR2
Performance Mods: Numerous
Suspension Mods: Some, but not enough
Exterior Mods: Just Right
1987 Buick Turbo T Dark Red
Low 11 sec sleeper
.030 4.1 block, PT6262E, & other odds and ends....
My Cardomain