400
bigbob
05-07-2004, 12:03 PM
can any one tell me how much power a chevy 400 sml blck can handel before it crakes
MagicRat
05-07-2004, 08:50 PM
It depends on how its built. As I recall, there were no stock forged crankshafts for a 400. You either used a cast one or spent huge $$$ modifying a 350 forged crank to fit. (requires building up the bearings with welding then machining them.)
Main bearing caps make a difference, most have only 2 bolts.
So, without a forged crank, say 450 HP and 6000 rpm, reliably.
With a steel crank and 4 bolt mains (or cap girdles) it will take 600 hp to blow it up.
BTW its not just big HP that ruins things, the really high revs or massive detonation (nitrous and too lean or a blower and too much compression) grenades most engines.
Main bearing caps make a difference, most have only 2 bolts.
So, without a forged crank, say 450 HP and 6000 rpm, reliably.
With a steel crank and 4 bolt mains (or cap girdles) it will take 600 hp to blow it up.
BTW its not just big HP that ruins things, the really high revs or massive detonation (nitrous and too lean or a blower and too much compression) grenades most engines.
bigbob
05-07-2004, 09:18 PM
it has a 4 bolt main and a steel crank shaft. its bored 30 over and soon to be decked before she goes in the car. 10.5/1 compression pistons 2 holley 4 barrels and the intake manifold was stolen off of it . not sure on the heads/headers or what not. it was a short block that was built up so its all good aftermarket parts what is ur guess on what kinda power itll have. were gunna put it in a nova and put nitrous on it. big slicks, and a race trany. any idea on the 1/4 mile time
macktoschool
05-12-2004, 01:00 PM
it has a 4 bolt main and a steel crank shaft. its bored 30 over and soon to be decked before she goes in the car. 10.5/1 compression pistons 2 holley 4 barrels and the intake manifold was stolen off of it . not sure on the heads/headers or what not. it was a short block that was built up so its all good aftermarket parts what is ur guess on what kinda power itll have. were gunna put it in a nova and put nitrous on it. big slicks, and a race trany. any idea on the 1/4 mile time
Are you sure it's a 400? I don't recall any 400 4 bolts. Anyway be very careful with the decking, as this changes the relationship between a lot of things ie: Intake to heads, Valve train height... I would opt for using head studs instead of bolts since already minimal cylinder wall to steam pocket thickness is now less due to the boring. As for power, depends on so much not listed. Stock, or Dart heads, Ignition, single or dual stage fogger, it really depends on how much money you have. Good luck at the track.
Are you sure it's a 400? I don't recall any 400 4 bolts. Anyway be very careful with the decking, as this changes the relationship between a lot of things ie: Intake to heads, Valve train height... I would opt for using head studs instead of bolts since already minimal cylinder wall to steam pocket thickness is now less due to the boring. As for power, depends on so much not listed. Stock, or Dart heads, Ignition, single or dual stage fogger, it really depends on how much money you have. Good luck at the track.
Murray B.
05-19-2004, 03:57 PM
[QUOTE=macktoschool] I don't recall any 400 4 bolts. /QUOTE]
Maybe it had one of those conversions. Shanons Engineering, Inc. used to do that sort of thing.
Maybe it had one of those conversions. Shanons Engineering, Inc. used to do that sort of thing.
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