how I know which new crate engine is which if engines stand side by side? maybe seller want to cheat and sell ls3 but make billing for ls376/525? labels with barcodes is easy to make. sorry, maybe is this funny question but in my country many sellers is cheaters.

thanks

 

I agree. How can you physically see any differences from an LS376/525 HP and a LS376/430 HP?
This is frustrating as no one seems to know the difference unless you pull the cam or pop the valve cover to see the springs are different(heavy duty) from the 430HP ?
Does GM stamp on the heads or block that the cam is ASA and or this motor is a 525HP?
Thanks much, -Matt
Yes, the dyno would tell all but that's really far down the install process to be finding this out.

 

The only clear indication is a sticker on the block, behind the driver's side head. The LS376/525 sucks by the way. The cam lope, and unburned hydrocarbons are terrible - as in the smell reeks. It makes only modest power for what it is, and the bucking and surging below 2000 rpm make it hard to live with on the street - to say the least.



You'd be better off getting a stock LS3 and putting a cam in that. All LS heads and blocks are stamped and indicate what they are.

You can find the casting numbers at the back of the block, again by the driver's side head.
LS3 Block (cstg) 12584724
12560626 1998-00 346 345 crossbolted block, Gen.III, "LS1"
12559378 1998-00 346 345 crossbolted block, Gen.III, "LS1"
12561168 2001-04 346 350-405 crossbolted block, Gen.III, "LS1/LS6"

The passenger side head will have the casting number at the front. (241, 853 are LS1 heads, 243 is an LS6 head).

More info here: https://ls1tech.com/forums/generatio...ory-heads.html

 

Get a stock LS3 with 430HP and put a GOOD cam in it.
Anything out there is better than the cams in the 480 or 525 HP crate engines.
And that is the ONLY difference between these engines. The cam. That's IT.