93 Sierra 1500 Engine needed

I need a New engine and the problem is that GM them self has told me they dont make the LB4 4.3L V6 anymore.:banghead: I was wondering if theres some sort of specilty retailer that deals in discontinued parts, also im told the reason that GM doesnt sell or make this type of engine anymore is because it was a limited edition. any help would be greatly appreciated.

Try a rebuildt. Jasper does a real good job.

Check out www.atk-engines.com

I beleave im going to go with ATK, but thank you both for your answers:)

I heard ATK was bought out from a Jasper rep.They were about to go out of buisness and were not doing good.Jasper has the better warranty and does upgrades and uses high quality parts

also some great complete crate motors here www.musclecarengines.com

I decided not to go the route of getting a new engine but with doing so i began to search the engine for the knocking issue and in doing so i messed up my Idle Air-Control. So I went and got a new one and installed it fine. but the issue now is the engine light is on, so i checked it and im getting a code 42 which says " The EST signal did not change when the ECM applied bypass voltage to the ignition module." which no one at the local auto-parts store seems to know what a EST is. Now a second issue arose, the TBI is surging at about 1500 rpms and goes away at about 1800-2000rpms but when i stop or slow down its ok but when it gets to 1500rpms again its starts surging again. Above or below 1500rpms it runs ok. once again guys thanks for any info possible.

EST is electronic spark timing Is part of the ignition module. Look for 4 wires coming out of the distributor and going to a small green box on the firewall. I have seen either the EST(small green box) bad or the module bad.

You may also want to make sure that your spark timing connector is not unplugged. This wire is usually a tan wire with a black stripe and has a black connector you disconnect to set the timing. This will also turn on the 'service engine soon' light when it is disconnected or if the wire is broken. It is located either under the hood behind the black relay/junction block cover on the passenger side of the firewall, or inside the cab in the wiring harness near the blower motor on the passenger side.

Wow thanks guys, i ended up taking it to the dealer because i could not figure it out and i needed it for work but what you guys described was the exact problem that the dealer fixed for me. Luck shined on me today cus the dealer didnt charge me but 25 bux. thanks alot guys.