Hi: I am new (referred by another member) to this forum, but it really looks great from the little I have viewed already.
Anyway, a friend has just bought a '93 that usually reliable sources report now has a rod permanently residing in the oil pan. We suspect the topend is OK (hoping to open it up this next week) and we're now trying to determine our options.
The salvage yard tells us the ONLY totally interchangable LT-1 motor is from a '92 'vette, and a '93-94 Camaro/Firebird. Anyone know if this is true? Why is a mid-90s LT-1 (like a '96 LT-1 motor) not interchangable?
If we're right and the topend is OK, does anyone know what varieties of "LT-1" short-block assemblies we can use to get back up and running (on the cheap- money is a little tight)? Or are we better off buying a "complete" LT-1 motor (got a quote from a yard @ $800 for a running LT-1), and selling off the remaining good parts of the broken LT-1??
Thanks! jj

 

Well if you buy a complete bottom end you can use the heads and intake on it.The opti on the 95 on are vented so if you buy a 95 or newer block you will have to get a vented opti.I think that should be it.If I missed something I am sure someone will let us know.

Rob.

 

The way the optispark is driven off the front of the cam changed in '95, that is why the guy is telling you that.

But as long as you got a COMPLETE engine it is irrelevant. However, the blocks are the same through all years.

 

Personally dude... I would take it apart and check the internals and see how extensive the damage is. I personally would not buy a used motor from a junkyard. If he's gonna sell it to you for 800, I think its better to spend another 200 and have your motor redone. Cast crank....300, rods...200, machine work and rings....300.....run you about 1000. Will definately last longer, not to mention the warranty

 

The big difference on the 93 F-Body LT1 is the speed-density prgramming, and the batch-fire injetors. As a result of the batch-fire injectors, the 93 intake manifold is different, along with the fuel connections and the fuel rails. The harness is setup to fire each bank of injectors simultaneously. The EGR and AIR connections to the exhaust manifolds are also different, and the AIR pump is mounted to the body, rather than the front of the engine as it is in 94 and up.

No reason you couldn't buy an engine from virtually any year F-Body, and swap your 93 intake manifold onto it. If you get a Y-body engine, you will need to swap the accesory brackets on the front, the exhaust manifolds and the intake manifold as well, since the Y-body is set up to supply fuel from the opposite side. Crank pulley/damper will also be different on a Y-body engine.

And, 93 and 94 F-Body LT1's are not the same. All the differences I mentioned above would apply only to the 93. 94 has sequential injection, MAF, engine mounted AIR pump, etc.

If you are talking "short block", there will be very few differences, and nothing that can't be accomodated. 96/97 F-Body have a crank position sensor that you can just leave unconnected. The Y-body block will have two knock sensors, one of which you will remove and replace with a plug.

Here's a link to a thread that discusses all the "differences" in the 93 F-Bodys.

 

As long as the engine is toast anyway, then before buying another LT-1 shortblock to bolt your heads to, ask yourself one question; "Is this a good time to go to a Gen I (LT-1 is Gen II and LS-x is Gen III) type block from Motown, so that I can have a 454 smallblock?"

You'll probably decide to stay with the LT-1, for a variety of reasons, but you should CONSIDER it now, before you begin spending money.