355 LT4 short block FS
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From: STL MO METRO EAST
355 LT4 short block FS
(Local pick up only located short distance from Saint Louis MO/Metro East IL area. Absolutely will not ship this) $1000
For sale 355 LT4 short block (started out as an actual Corvette 4 bolt main LT4 engine). I have a copy of the official Salvage Certificate that has proof of what car it was removed from and actual milage. Was gone through and rebuilt to the 355 set up when the engine only had approx 30,800 miles. Work was professionally done and was balanced and blue printed too. I have the blue print records/receipt as proof of what the specs, clearances and parts are:
(overview from the shop invoice receipt)
block was thermo'd, bore and hone with plates, decked, balanced crank, recon rods, R&R cam bearings, R&R freeze plugs, regrind crank, forged pistons, moly rings, HV oil pump, and ARP bolts
I have since put only 4K miles on this since. Cylinders still have great looking cross-hatching that you would want to see since this has almost no miles on it. Carbon that is visible on pistons and cylinder walls comes off very easy when cleaning. Still has cam bearings, flexplate installed along with the a stock F-body oil pan and aftermarket quality oil pump too. It is assembled with the following:
Speed Pro forged pistons flat top 30 over with DUROSHIELD antifriction skirt coating, which reduces friction and scuffing and delivers improved performance and longer life. Also has moly ring sets
LT4 Connecting rods
LT4 roller timing set (GM item made by Cloyes specifically for LT4): Stock LT1 has powdered metal butt link chain drive for the camshaft and water Pump. LT4 has smaller but stronger steel roller chain. Although it seems that the new chain and sprockets would reduce mass, The cam sprocket was left solid, rather than webbed, specifically for additional mass. Increased inertia in the system reduces the tendency for cam torsion
Real LT4 crank The crank itself was improved via something called undercutting and rolling. Undercutting is the machining of a groove into the corner of a journal. Though this would seem to weaken the crank at that point, it actually makes it stronger where tensile stress is most likely to cause sudden failure. Rolling the undercut introduces compressive stress to the area. This makes it more durable, because potentially catastrophic tensile stress generated during high RPM operation must first overcome the compressive stress before that area of the crank is subjected to tension. Undercutting, a groove cut into the corner of a journal, looks counterintuitive, but makes a crankshaft stronger where tensile stress is most likely to cause failure. By undercutting and then rolling it, compressive stress is introduced. Tensile stress during high-speed operation first has to overcome the compressive stress before there's any tension on the joint. And as tensile stress is what breaks crankshafts, undercutting and rolling make the crankshaft stronger
Nodular iron main caps : These LT4 components are considerably stronger than their LT1 counterparts and resist failure at higher RPM's.
Teflon rear seal: Offers improved durability over the standard LT1 crank seal.
For sale 355 LT4 short block (started out as an actual Corvette 4 bolt main LT4 engine). I have a copy of the official Salvage Certificate that has proof of what car it was removed from and actual milage. Was gone through and rebuilt to the 355 set up when the engine only had approx 30,800 miles. Work was professionally done and was balanced and blue printed too. I have the blue print records/receipt as proof of what the specs, clearances and parts are:
(overview from the shop invoice receipt)
block was thermo'd, bore and hone with plates, decked, balanced crank, recon rods, R&R cam bearings, R&R freeze plugs, regrind crank, forged pistons, moly rings, HV oil pump, and ARP bolts
I have since put only 4K miles on this since. Cylinders still have great looking cross-hatching that you would want to see since this has almost no miles on it. Carbon that is visible on pistons and cylinder walls comes off very easy when cleaning. Still has cam bearings, flexplate installed along with the a stock F-body oil pan and aftermarket quality oil pump too. It is assembled with the following:
Speed Pro forged pistons flat top 30 over with DUROSHIELD antifriction skirt coating, which reduces friction and scuffing and delivers improved performance and longer life. Also has moly ring sets
LT4 Connecting rods
LT4 roller timing set (GM item made by Cloyes specifically for LT4): Stock LT1 has powdered metal butt link chain drive for the camshaft and water Pump. LT4 has smaller but stronger steel roller chain. Although it seems that the new chain and sprockets would reduce mass, The cam sprocket was left solid, rather than webbed, specifically for additional mass. Increased inertia in the system reduces the tendency for cam torsion
Real LT4 crank The crank itself was improved via something called undercutting and rolling. Undercutting is the machining of a groove into the corner of a journal. Though this would seem to weaken the crank at that point, it actually makes it stronger where tensile stress is most likely to cause sudden failure. Rolling the undercut introduces compressive stress to the area. This makes it more durable, because potentially catastrophic tensile stress generated during high RPM operation must first overcome the compressive stress before that area of the crank is subjected to tension. Undercutting, a groove cut into the corner of a journal, looks counterintuitive, but makes a crankshaft stronger where tensile stress is most likely to cause failure. By undercutting and then rolling it, compressive stress is introduced. Tensile stress during high-speed operation first has to overcome the compressive stress before there's any tension on the joint. And as tensile stress is what breaks crankshafts, undercutting and rolling make the crankshaft stronger
Nodular iron main caps : These LT4 components are considerably stronger than their LT1 counterparts and resist failure at higher RPM's.
Teflon rear seal: Offers improved durability over the standard LT1 crank seal.
Last edited by JACLT1S; Dec 31, 2010 at 09:22 PM. Reason: found more info to provide
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