Difference between GM engines.

[Teardrop]

I see them get talked about in terms of L36, L32, L67, etc...

I know them better as say 3800 (and the series II), 3100, 3.1, 3.4 etc...

So just to keep on the up-and-up, what are all the series of V6 GM engines and how they correlate to the specific size? Like is an L67 is series II SC, etc?
And where do these terms like L67 and such come from? Something in the VIN or where?

Most specifically, with my 94 GTP having the 3.4 NA, what one do I have exactly in the "L" sense?

Just curious here, trying to be more educated about the engines.

Thanks.

[Jonpro03]

Your 3.4 DOHC is the LQ1. I believe these are the RPO codes. In my car, the RPOs are listed on the spare tire cover in the trunk. It's has lots of RPO's on it like BE3 for suspension..

Engine RPO's that I know are

LH0 3.1 MPFI
LG5 3.1 Turbo
LQ1 3.4 DOHC
L82 3100 small port
LG8 3100 large port
LA1 3400
LX9 3500
LZ4 3500 VVT
LZE 3500 VVT FLEXFUEL
LZ9 3900 VVT
LZ8 3900 VVT (DOD?)
LGD 3900 VVT FLEXFUEL

Sorry, I don't know a whole lot about the evil 90* motors but...
L27 3800 S1
L67 3800 S/C S1-2
L26 3800 S3
L32 3800 S/C S3
The 90* motors are dead now, thank god. They were killed by the far superior 60*

[[ChaosweaveR]]

Exactly, the RPO codes GM uses to classify which motor is which, same for suspension and brake systems among other things.

Of course, there's the newer 60*V6 DOHC motors too

LY7 - 3.6L DOHC
LLT - 3.6L VVT DOHC

I know there are a few other variants of the 3.6L DOHC V6, but I'm not 100% sure on the RPO codes.

[pocket-rocket]

I wish my 92 had an LSx, more specifically an LS9 >.>