would LT1 parts fit on my 69-80 sbc 350 block??? what year parts would fit?? thanks alot guys I'm sort of new at this stuff thanks
kmnracer10

 

GM's generation II engine, the LT1, was introduced in '92 in the corvette and was rated at 300hp. In 93 the new 4th gen F-body arrived with the LT1 rated at 275hp. There are some significant differences between the new engine and earlier small blocks. Among them are the opti-spark distributor located on the front of the engine behind the gear driven water pump and crank balancer. The block, heads, timing cover, water pump, intake manifold and accessory brackets are not interchangeable with the earlier smallblocks. Engine mounts and the bellhousing pattern remain the same. There were early and later versions of the aluminum head. The early head had a casting number of 10128374 and the later head had a casting number of 10128649.
The LT1 is reverse flow cooled meaning the water flows through the heads first then the block, instead of through the block and then the heads as is standard. Reverse flow cooling is a function of engine design and does not require a special radiator. An overflow tank is necessary to ensure there is no air in the system.
There are some differences between LT1's. The Corvette got 4 bolt mains and Aluminum heads. The F-body cars got 2 bolt mains and aluminum heads. The '94 - '96 Buick Roadmaster, Cadillac Fleetwood, Chevrolet Caprice, police cars and the Impala SS got the 5.7L with 2 bolt mains and cast iron heads and was rated at 265hp. There was also a 4.3L LT1 available in the big cars which is indistinguishable from the 5.7L, except for the different casting number and 4.3 cast into the top of the block just ahead of the bellhousing flange.


In short, NO

 

so how would i be able to tell if the parts i have will fit the block???

 

The crank will not fit since the later LT1 is a one piece rear seal. The pistons would work but there are better ones available. The rods will fit but, there are better available. The heads will bolt on but the reverse cooling scheme would negate the function. As you can tell; there is little value in trying to use any parts from a late LT1 in an early block. Cam does not work since there is no cam drive gear for the distributor. Intake will not work since there are no cooling provisions for earlier style heads. I hope that answers your quesions.

 

ok well i have 5.7L votec heads, GM performer intake, and a melling performance cam, all which are brand new, would any of this stuff work??? how could i tell if it would work?? basically im backed in a corner what would you do???

 

In the off chance they do fit, they wont work. What kind of car are you planing to put these in? You can buy plenty of parts for an old smallblock that will give you plenty of HP. My advice would be either get a new block for your new parts or get old parts for you old block.

 

vortec heads require vortec intakes, cam is a cam, make sure it's for a sbc and it's got a distributor drive gear, performer intake (assuming it isnt a vortec one) would bolt right up to your stock heads and give a nice increase in torque and power over bonestock

 

alright thanks alot guys im glad i found this out before i bored and cleaned the engine block and started to put it all back together, thanks again
kyle

 

I remember they called the HI-PO 350's of the 70's LT1's also


Wade

 

vortec heads will work great, they are 64cc so use that to check your compression ratio, the intake ports and flow are better than camel hump heads or any others made for your year block, and there are all kinds of vortec intake manifolds, I use the edelbrock Vortec Performer RPM, the stock springs are not very good you can only use a cam with under .480 lift so get some beehive springs, unless you want to mill the spring pockets in the head to allow taller springs that wont bind past .480 lift, and you have to use self centering rocker arms. But they will make a lot of power especially for $500 a pair assembled! best ho for the money on an older engine!