ss67

hello i am getting ready to take on a 5.3 swap into a 63 buick rivera.the guy has a complete engine and trans,harness,fuse box,ecm and a box load of other stuff.i need help figuring out what "gen" the engine is.im reading certain ones are not worth the swap cause of gas pedal and ecm.but i dont know thats why i am here. online this looked like the best place for ls info.i took some pictures of engine and trans.but the #s i have dont match what im finding on the internet.on the back of the cast iron block is a # 12578181 behind left cyl head looking at the engine from the front. on the cylinder head is a #7109025610 .the transmission has a tag on it 8DCA 24226651 below that YTO 7159 below that 618DCAHB343428 .just trying to figure out what im working with and if its worth doing with the engine and parts.we already have .thank you very much and i appreciate your time

G Atsma

See if the block is actually 12576181. That comes back to Gen IV 6.0 truck engine. I didn't see a 12578181, but I might not have caught it
Upon further investigation, all iron truck blocks starting with 125 continue to 125761-- . None with 125781--.

ss67

ok thank you i will try to get a better look at it.it could be a 6 .thats a 6.0? he was told a 5.3 .would that be a good swap and is it difficult to tap/power the harness and will i need a gas pedal or have to program/immobilizer .or do you think i would be better getting a aftermarket harness.sorry to ask so many questions.my friends father passed away. it was his dads dream he wants to finish it for memorys and to keep.so the LS swap is new to me.i have done other engine swaps so i know what can be involved would like to make as painless as possible and reliable.please tell me what you think is my best attack plan.and let me know if i can provide any info or picks.thank you very much your time and knowledge is appreciated

Project GatTagO

iTrader: (7)

Just look at the location of the knock sensors. gen 3 has them in the valley cover and gen 4 on the sides of the block.

Andrew

Haggar

Usually 6 liters have a big 6.0L cast into them, and smaller ones say 4.8L / 5.3L, right under the block number.

Look at the crank sensor on the passenger side rear, see what color is the plastic on it: Grey or Black?

As noted, the LY6 is 12576181, but many people misread it as 8181. If you have an LY6, it's a very good starting point.

Very likely you have a Gen IV engine. I believe the "8" in 8DCA means 2008 Model year, I believe. You might have a 6L80e transmission then. From this thread: https://ls1tech.com/forums/conversio...80e-6l90e.html
The other numbers on the trans look a lot like they relate to the transmission controller inside the trans.

ss67

thank you very much just got the engine and trans dropped off .getting the car this saturday .thank you for the info .i dont know much about the breakdown on ls engines .so LY6 is a good start for a conversion.

G Atsma

Are you ss67??