Viprklr

Hi all,

I was wondering if there was a quick way to identify the LS1 & LS6 by just looking in the engine bay. Now don't go saying "Just look at the fuel rail covers!?!? Duh!". I've already thought about that. Any help would be appreciated.


Matt

427Z

yep. there is a 243 stamped on the heads. i forget what the # is for an ls1 but its not 243.

standing on the passenger side, you can see it toward the front of the head

the 243 is on the block too but not shure where

Viprklr

Thanks for the reply. I have aftermarket heads...so you think that 243 is on the block somewhere? Anyone know where that might be?

Thanks,
Matt

427Z

i know its on there, it wont be hard to find. just look. if you find a 3 number stamp and its not 243, then its the ls1 block.

Viprklr

Anyone else have specifics?

Thanks,
Matt

Last C5

The engine ID number is on the block just behind the driver side head.
(not the easiest thing to see) If the eighth digit is an S its an LS6 if its a G its an LS1.

Lancer033

wouldn't the block #s be the same on LS1s and LS6s since they started using the same blocks in mid 2001?

Scott04Z

There is usually an LS6 sticker on the top of the throttle body. If you just have the block then it is identified in the numbered code stamped on the block.

Viprklr

Thanks for all the help, but a picture or a more detailed description of the location of the stamp would be appreciated. My engine compartment is fairly dirty and may be obscuring the number. I couldn't find it when I was looking earlier.

Thanks for any help.

Matt

Mike94ZLT1

Early LS1's have the bullseye stamped on the top edge of the block, above the timing cover. LS6 blocks do not. This was true until 02. My best friend just bought an 04 GTO and it does not have ther bullseyes, and I don't believe it came with the LS6 block. The intakes are easy to tell apart, in 01 when they started using them there were brass inserts on the passenger side for the throttle cable bracket to go on f-bodies. GM made them all this way to save $$$. 00 and earlier cars look the same as they dont have EGR like f-bodies do, but they also lack the brass inserts.

Viprklr

I have an aftermarket intake. Anybody else?

Matt

dragon84

There is???

Stock Man

I am going to have to start looking for numbers. I have an '02 which is supposed to have the LS-6 block and intake manifold but like the above I don't know how to check this. Great thread. I hope we get more info from the people in the know.

Last C5

The blocks probably are the same, the ID number identifies which motor it is.

SteveDoten

how to tell if you have an ls6 block w/ pics
http://www.ls1tech.com/forums/showpo...86&postcount=8

Red C6 Z06

I've got an LS1 sticker on my throttle body, so it wouldn't surprise me to see an LS6 sticker on an LS6.

SteveDoten

i believe the only t/b stickers were in 04 on the lemans z06

Gonzo

Just a thought, can't you identify the LS6 via the Vin #. As long as its the original engine the Vin should have a digit the identifys the engine

SteveDoten

8th digit is S=ls6, from post #6

Tino

I have an 04 LS1 vert and the heads are stamped 241