i've been working on this car for 3 years, and have put less than 200 miles on it. the only reason i've gone that far is because i live 30 miles from civilization.
it started out as a 91 rs 305/t5 roller.
i completely redid the suspension: sfc, lca, panhard bar, 9bolt 3:73 posi(paid 300 for a shop to install full rebuild kit, now it leaks at the axle seal), z28 kmember+springs+steering box, poly bushings all around, wonder bar, 4 piston brakes, new rear springs+shocks+front struts.
t56 with centerforce df clutch, spohn trans xmember, aluminum driveshaft with spicer ujoints.
383 sbc with edel perf rpm heads 11:1 compression, dual plane intake, holley 750 dp, ran best of 13.55@107. too much compression, put dart iron eagle 215 cc runner 72 cc heads, single plane intake and the biggest voodoo hydraulic cam they make 284/292, 525/546. didnt get it to the track, but seat of the pants it was way faster. then lo and behold, a 3 inch crack in the block below the #5 cylinder. if it wasn't for bad luck with this car i wouldnt have any!!!!!!!!!!!!!!!!!!!!!!!!!!!!!

 

First off, where did you get your 383? I have run faster than 13.55 with a 350...
A cracked block also makes me suspect who you got the engine from...

I've never heard of too much compression at 11 to 1...

You need to re-tighten your pinion nut on the rear axle; that's usually why they leak.

 

i got the short block from rpm performance machine(eagle rods, sealed power pistons, eagle crank). too much compression= dcr=8.94, too much compression to run on pump gas. after the cam and heads= 8.22. but that is besides the point. i finally got the motor running and the block had a crack in it! i was tempted to put some ak rounds through the car!!!

 

I'd be more tempted to put rounds through the office of rpm performance machine. Sounds like you got a repaired or junk block with your kit...