[GTJimbO]

So, I've been collecting some workshop books on the Gen III/IV V8's, and I'm still learning, coming from the world of Swedish turbo cars (Saab -- made in Trollhattan, Sweden, so Goats and Trolls. There's a theme there somewhere!).

LS1/LS6 I'm gathering are Gen III, but what makes the LS2 Gen IV -- what differences are there -- what makes an LS2 an LS2, and what makes an LS1 an LS1?

I suspect that the LS6 was iron block 6 liter only, whereas the LS2 is simply the LS6 with an aluminum block? Or am I way off base here?

Thanks, guys.

Jim Miller

'06 GTO, M6, 18", Phantom Black, just a hair under 3 weeks old
'02 Saab 9-5 Aero, Remus exhaust, Forge bypass valve
'97 Saab 900 Talladega Edition, Abbott Motorsports ECU, springs, etc. Selling
'93 Saab 900 Commemorative Edition, JSP Motorsports ECU, springs, much more...
'91 Saab 900 Special Edition, stock

Saabs (Trolls) are fun, but in this case, Goats eat them, not like the fairytale!

 

[muohio]

So, I've been collecting some workshop books on the Gen III/IV V8's, and I'm still learning, coming from the world of Swedish turbo cars (Saab -- made in Trollhattan, Sweden, so Goats and Trolls. There's a theme there somewhere!).

LS1/LS6 I'm gathering are Gen III, but what makes the LS2 Gen IV -- what differences are there -- what makes an LS2 an LS2, and what makes an LS1 an LS1?

I suspect that the LS6 was iron block 6 liter only, whereas the LS2 is simply the LS6 with an aluminum block? Or am I way off base here?

Thanks, guys.

Jim Miller

'06 GTO, M6, 18", Phantom Black, just a hair under 3 weeks old
'02 Saab 9-5 Aero, Remus exhaust, Forge bypass valve
'97 Saab 900 Talladega Edition, Abbott Motorsports ECU, springs, etc. Selling
'93 Saab 900 Commemorative Edition, JSP Motorsports ECU, springs, much more...
'91 Saab 900 Special Edition, stock

Saabs (Trolls) are fun, but in this case, Goats eat them, not like the fairytale!

The LS1 and LS6 share the same aluminum block. Both are 5.7L where the LS6 had different heads, cam, and intake. The intake was later shared with the LS1. The LS2 is a 6L aluminum block that has changes not only in size but offers DoD, throttle by wire, and so on. The LT1 was the iron block 5.7L that was offered in earlier F-bodies and Vettes.

 

[Clueless]

I have a question that may be related to what Jim was asking, so I'll tack it on here. It is just a mild curiousity thing, and ya'll have to forgive that I'm not that great with engine specs.

Is the 6.0L an engine that is newish for GM and designed from scratch as a 6.0? Or is a 5.7 that was bored out?

I'll throw my math below, which seems to support a bored-out 5.7 theory. IIRC, the conversion factor for liters-to-cubic inches is 61. And, the common bore sizes people used to talk about back in carburetor days were .3 and .6.

So, .3 * 61 = 18.3 addition cubic inches.
5.7 * 61 = 347.7 cubic inches

347.7 + 18.3 (additional for a .3 bore) = 366 cubic inches

6.0 * 61 = 366 cubic inches

Car manufacturers--at least American manufacturers of V8s--seem to keep reusing the same engine blocks, as it is probably more monetarily efficient, and why make something new from scratch when you can modify an existing design, or just use an existing design? Therefore, given that there are still engine sizes today that were used over 20 years ago and GM likes to reuse the same general designs, and given that the math adds up from what my rusty mind remembers, I would think we just basically have a 0.3 over bored 350 (as the 5.7 used to be called when I guess they were doing a bit of inflation math).

Does this sound right or am I totally off base?

 

[baron_iv]

Your figures seem to be correct, but they're not the same block. The casting is different. I don't know if it's 100% *new* engineering, because it shares some of the LS1's features, but also adds new things like Displacement on Demand (which wasn't activated on the GTO for some oddball reason).

 

[Clueless]

Interesting. I didn't know there were LS2s with DoD. I know that was in the Camaro Concept, but thought it was something they either worked in just for the concept, or were proposing for the future.

 

[baron_iv]

I suspect that it would just take a computer change/upgrade to make it work. I'm not sure about that though, so don't quote me on that. I do know that the LS2 is DoD-ready though.
If there was anyone who could turn it on, I'd get it turned on in a heartbeat, I'd love to get 30+ mpg!

 

[gto_lady04]

Here's great article on GM's DoD, it includes an interview with Chris Meagher, assistant chief engineer of small-block truck engines at GM.

http://www.popularhotrodding.com/features/0405phr_gmdod/