I need some help. I am looking at a bbc that is supposed to be a LS5 it has the cowl induction air cleaner. but the intake is missing. The heads are supposed to have been replaced with somethin that was supposed to have been better that stock but who knows what his oppinion of better than stock was. Looking at moretech maybe I am missing somethin but how do you tell for sure i it a LS5 block. What would an ls5 motor be worth?? What would the air cleaner be worth? And does it being a ls5 make it worth more than a regular 454?? I suppose this question has been asked before but I couldn't find it so thanks for answering it again.

how do you tell for sure it's a LS-5 block ?

And does it being a LS-5 make it worth more than a regular 454 ?
A real LS-5 engine block will have the casting number [3963512], on top at the rear of the block.!!

Yes a #3963512 block is worth more, than most other 454 engine blocks ...

http://i24.ebayimg.com/05/i/001/0d/54/4dfd_3.JPG

A real LS-5 engine block will have the casting number [3963512], on top at the rear of the block.!!

Yes a #3963512 block is worth more, than most other 454 engine blocks ...

http://i24.ebayimg.com/05/i/001/0d/54/4dfd_3.JPG
Thanks for the info thats exactly what I needed to know.
Cool now I guess the other question would be does the ls5 have Steel Crank and good rods OR not??

Don't go by just the casting number alone as the 512 block was used for more applications than just the LS5 :
3963512....454.......70-76...2 or 4 bolt

Get the Engine ID Number (or all if you can) as shown in the pic ,if it's gone due to surfacing ,then you've no way to determine if it was an actual LS5.
http://www.yearone.com/updatedsinglepages/Id_info/gm_engine_id/gmidimages/endinedetail1.jpg

Post the year in question and I'll post the codes.

Don't go by just the casting number alone as the 512 block was used for more applications than just the LS5 :
3963512....454.......70-76...2 or 4 bolt

Get the Engine ID Number (or all if you can) as shown in the pic ,if it's gone due to surfacing ,then you've no way to determine if it was an actual LS5.
http://www.yearone.com/updatedsinglepages/Id_info/gm_engine_id/gmidimages/endinedetail1.jpg

Post the year in question and I'll post the codes.
Ok I will do that when I go and look at it a little closer. I don't want to act too overly excited I just want to pick it up if we can come to a reasonable price. I don't like buying somethin that I don't know for sure what it is.

remember , the 3999289 casting was also used for the LS5.
my #s matching LS5 is a 3999289 block.

Here too!

Post the letters at the end of the long VIN number string that should still be on the deck pad that's above the pass side top water pump bolt for starters so we can decode what it started life out as if it's not still a virgin.

Otherwise, tear her down.

pdq67

Here too!

Post the letters at the end of the long VIN number string that should still be on the deck pad that's above the pass side top water pump bolt for starters so we can decode what it started life out as if it's not still a virgin.

Otherwise, tear her down.

pdq67
I will post the numbers in the next day or 2. Its buried in the back of a friends garage he is supposed to unearth it in the next day or so

The LS-5 will have a steel crank
ALL the BBC rods are forged but the LS-5 did not get 'dimple' rods, the premium units.
Dreis454 Dan has a 72 454 and '289' block
The blocks used/dated for use in 1970 are worth more than others ONLY if the buyer is looking for a 'correct' engine.....
Most of the period blocks are bought-up by guys who re-stamp them and make 'new' LS-6 and LS-5 cars.

The "LETTERS", post back the letters at the end of the long VIN number string that should be on the deck pad.

Thanks and we will search away.

pdq67