The LS engine thread:

[Stewart G Griffin]

2) But anyways, could we get back to the actual description/history/segments of the LS engines?

What do you want to know?

Basically a general overview of the whole LS series.  For example is the LS 2 the same engine as the LS 1?  For example if talking about 305's and 350's, i know that they are basically the same engine except different bore size and heads.  Really, all the sbc engines (except the 400) are basically the same engine;  i'm familiar with the history, size progressions, interchangablility of the SBC.

However, when it comes to LS engines, i'm lost.  i do know that they first started in 97 with the corvette and camaro.  Other than that, i'm lost;  i mean is the 700hp motor found in the corvette zr-1 really the same engine as in an impala/grand prix?

2) i somewhat agree that the LS engines are not exactly an earth-shattering "improvement" over the sbc, but they are lighter.  i'm mainly interested because the cars i'm looking at have this engine and i want to know more about them.

[joesgarage71]

 go to my earlier post and click on that link and read.
 Steve

[Captkaos]

The original LS motors are the Gen III, they were updated in 2004 to handle Displacement on Demand and were know as Gen IV, they all share the same basic architecture, but most people generalize like is done on the GEN I and Gen II calling them SBC.

LS1 is a 5.7L motor, LS2 is a 6.0L motor, otherwise they are identical in architecture.
The LS9 is 7.0L based on the LS3 which is based on the LS2, but still same architecture.

Simplifying it this way, there are basically 4 versions of the LS:  LS1, LS2, LS3 and LS4.  The LS4 is similar to the others but was redesigned from FWD use.  The 1,2,3 are udated versions allowing more displacement with the same longevity.

FYI The 99-up pickups use the same LS architecture.

I just read over Joes link and it pretty much says the same.

[eventhorizon66]

Hey Capt I think you meant the LS7 is a 7.0L.  The LS9 is a 6.2L like the LS3.

It should also be noted that the LS3, L92, LS7, and LS9 all have larger rectangular intake ports.  The LS1, LS2, LS6, and all 4.8, 5.3, and 6.0L truck engines have the cathedral shape port.  And the cathedral shape is not for the purpose of increased flow or swirl but rather is an effort to have the injectors fire at the back of the intake valve.  Clearly, since the later higher performing engines feature rectangular port entry shape, this injector positioning was deemed unnecessary.

[Stewart G Griffin]

So basically all LS engines are basically the same and the number after is just a displacement difference?

Also, it seems as thought the ls4 is also the same but just a slightly shorter crankshaft to fit FWD applications?


2) Upon further research, the impala ss cannot outrun a hemi challenger--it is a about a second slower 1/4 mile.   But who cares, i just like the car.

[DnStClr]

http://www.gmperformanceparts.com/Parts/showcase_detail.jsp?engine=2

[Captkaos]

Hey Capt I think you meant the LS7 is a 7.0L.  The LS9 is a 6.2L like the LS3.

Oops, typo, sorry, I was thinking to far ahead while I was typing....

[team39763]

I love these engines.  Most efficient smallblock ever built in my mind.  They are very modular and the variations provide a ton of factory choices when wanting to build one.  They are compact, can be really light, they get better than decent mpg's, can be used as a supercar engine, can run down the drag strip, can tow in a truck, or cruise.  The only real problems I have dealt with so far are rings and stuck valves.  The factory heads and intake are top notch, the low riding fuel injection setup is versatile. 

 ;DI'm a fan.

What problems have you had with the rings?  I think I may have had a problem with stuck valves at one time.

[jimbo]

I love these engines.  Most efficient smallblock ever built in my mind.  They are very modular and the variations provide a ton of factory choices when wanting to build one.  They are compact, can be really light, they get better than decent mpg's, can be used as a supercar engine, can run down the drag strip, can tow in a truck, or cruise.  The only real problems I have dealt with so far are rings and stuck valves.  The factory heads and intake are top notch, the low riding fuel injection setup is versatile. 

 ;DI'm a fan.

What problems have you had with the rings?  I think I may have had a problem with stuck valves at one time.

Just a few friends with nitrous had problems with the ring lands.  The worst valve problem I had with valves, I think was due to dry gas, my 5.3 bent all but 5 pushrods and just as many valves on startup.  I put it back together with just a valve job and not a problem since.

[Stewart G Griffin]

Well, it looks like the new position at work will not come thru.  So, for all practical purposes, i /we can assume no promotion for the next forseeable future;  This also means lesser income which means i probably won't be getting a more recent LS powered car---which also means more time to work on pre-existing but less current rides.  Plan now is to work on the truck--get it more "commuter ready." 

i have also thought that, even with the increased income (80K), it still would not really make financial sense to buy a 20K ride, when i have a pre-existing truck which would probably only take $100-200 to get "commuter ready."   

a) my concerns were mostly of the time/low-expertise factor, thinking it would be less hassle to get a more current car i could bring to the dealer for service;  i would have to fix the truck myself---which as we know in my case takes too long.

b) it would just be nice and exciting to have an impala SS.



But, we can still discuss the LS engines for when things change.

1) i think one of the advantages of an LS motor is that there are aftermarket turbo kits which are really compatable with the LS's EFI setup.  i don't think there are any commercially available turbo kits for carbed small blocks.  i believe there is a kit available from banks which will utilizes EFI for a SBC, but that's megabuck.

2) Has anyone swapped in an LS with the displacement on demand system?  It would be interesting to see the MPG results.

[eventhorizon66]

b) it would just be nice and exciting to have an impala SS.

Doesn't sound too exicting to me.

http://www.caranddriver.com/reviews/car/06q2/2006_chevrolet_impala_ss-road_test

1) i think one of the advantages of an LS motor is that there are aftermarket turbo kits which are really compatable with the LS's EFI setup.  i don't think there are any commercially available turbo kits for carbed small blocks.  i believe there is a kit available from banks which will utilizes EFI for a SBC, but that's megabuck.

Everything from Banks is megabuck.  Capt is working on turbocharging a TPI 350 using a "remote mounted" STS turbo system.  So there are practical ways to turbocharge Gen 1 SBC's.

[Captkaos]

We have turbo'd a couple of LS motors with STS kits with great results.  Easily 100hp with 5lbs of boost.
I don't think they have a app for the Impala, but anything can be fabbed.

[SUX2BU99]

Generally speaking, carbs and turbos don't often make for a nicely compatible pair. Blow-through and draw-through designs each have their own disadvantages. A blow-through design is probably better, as long as you get a carb designed for positive pressures. Again though, other opinions may vary on the subject.

IMO, while the LS motor architecture may not be entirely thrilling technically-wise, it's a big improvement over the SBC. It's like they put into the LS what they learned over the years that could improve the SBC and made it a very impressive pushrod motor. Compared with say the 505 HP LS7, I'm not sure how docile and streetable an equally-performing SBC could be. Perhaps with enough computer programming and a fancy enough EFI system, this could be done.

[eventhorizon66]

Compared with say the 505 HP LS7, I'm not sure how docile and streetable an equally-performing SBC could be.

Not trying to downplay what you said, I agree wholeheartedly, but if it were a 500hp 427 SBC, it could be very docile, would produce much more than 470 ft-lbs, and would only need to rev to less than 6000.  Oh, and it could be built for MUCH less than the LS7 crate's price.

[jimbo]

I really dislike the sts rear mount kits. 99% of the sts cars I have seen run are turds from a stop.