Future of LS series of Engines

[1981DFA]

Here is my thoughts with the LS series of engines. They (all LS engines) already get great fuel mileage for what they are. Please correct me if im wrong but generally speaking doesnt direct injection improve mpg's and power? From my experience the LS engines also like a small bump in compression, (1 maybe 2 tenths) which also improves power and MPG's correct? I dont think they need to leave the line of small block LS series engines just yet as i think they will have an upper hand in the maket if they could find a way to do the things i have stated and be able to keep the engines up to their testing standards. Upper hand meaning overall power and fuel economy. Just my .02. Please add your thoughts!!!

[slick rick]

What's this generation V engine I'm hearing about

[1981DFA]

Gen V engines? Is this what they are doing with the LS engines? If so i did not know that!!

[DGthe3]

The Gen III/Gen IV aka 'LS Series' is coming to an end soon. They are being replaced by the Gen V, which is said to be known as the 'LT Series'.

We have few hard facts, but from the sounds of things the engines will be all aluminum (including the truck engines), feature direct injection, and variable valve timing. Active Fuel Management will likely stick around and be improved upon. Additionally, its expected that they'll rev a bit higher than the LS engines typically did.

I would assume that the compression ratio is going up because you can use direct injection to cool the air charge, which then reduces the chance of pre-ignition. You can also use it to inject fuel just prior to when its supposed to ignite, eliminating the chance of preignition, but I don't think automakers are doing that just yet. Anyway, look at the V6 in the Camaro. It has an 11.5:1 CR and is tuned to run on regular, compared to the 10.7:1 for the LS3 (10.4 in the L99) which recommends premium. Imagine what they could bump it up to for an engine that is supposed to run on premium ...

[fielderLS3]

Originally Posted by DGthe3

The Gen III/Gen IV aka 'LS Series' is coming to an end soon. They are being replaced by the Gen V, which is said to be known as the 'LT Series'. ...

I've always assumed that the Gen Vs will just be a refresh of the current small blocks, with some of the more modern goodies added, and not an entirely new design. Is that right or wrong?

[DGthe3]

Originally Posted by fielderLS3

I've always assumed that the Gen Vs will just be a refresh of the current small blocks, with some of the more modern goodies added, and not an entirely new design. Is that right or wrong?

I don't know. I think its going to be more involved than the changes made from the Gen III's to the Gen IV's. Thats based on a few of the rumours that I've heard. They might be changing the position of the cam shaft, moving it up a bit higher, for reasons that I don't remember. I think it might have to do with helping them run at higher rpms easier. They're also rumoured to be capable of supporting a 3 valve cam-in block design, something which was proposed for the gen IV's (namely the LS7) but never came to fruition. Time will tell if its been abandoned again or not. But the point is, if they are working on those sorts of things (and who knows what else) then I'd say that the Gen V is a ground up redesign and not just a small update like the Gen IV's were.

[Mr. Wyndham]

Originally Posted by DGthe3

I don't know. I think its going to be more involved than the changes made from the Gen III's to the Gen IV's. Thats based on a few of the rumours that I've heard. They might be changing the position of the cam shaft, moving it up a bit higher, for reasons that I don't remember. I think it might have to do with helping them run at higher rpms easier. They're also rumoured to be capable of supporting a 3 valve cam-in block design, something which was proposed for the gen IV's (namely the LS7) but never came to fruition. Time will tell if its been abandoned again or not. But the point is, if they are working on those sorts of things (and who knows what else) then I'd say that the Gen V is a ground up redesign and not just a small update like the Gen IV's were.

They've already invested nearly a billion dollars into the program, including plant retooling at multiple locations. It's real enough...they keep referring to a "revolutionary new combustion process".

And they intend to maintain the same bore-center spacing dating back to the very first Chevy Small Block. GM has several interesting press releases out on the engines that are decent reads.

You *may* need to agree to media terms and conditions to get into here. But it shouldn't require a password or anything like that:

http://media.gm.com/100Msmallblock

[meissen]

Originally Posted by DGthe3

The Gen III/Gen IV aka 'LS Series' is coming to an end soon. They are being replaced by the Gen V, which is said to be known as the 'LT Series'.

We have few hard facts, but from the sounds of things the engines will be all aluminum (including the truck engines), feature direct injection, and variable valve timing. Active Fuel Management will likely stick around and be improved upon. Additionally, its expected that they'll rev a bit higher than the LS engines typically did.

Absolutely cracks me up that we're going to have an LT1 engine in a Camaro again...

[SC2150]

The future is direct injection on the v8's for sure. The current LS block design is not strong enough for the higher compression the DI can run and for economy & power DI allows CR's over 11:1 without the issues of detonation. This is because the fuel is not introduced unitl just before the pistion reaches TDC on the compression stroke so there is no early fuel air mixture to ignite prematurely. I'm pretty sure the single cam push-rod design will go away as well as overhead cam designs are mor efficcient and stable at higher RPM's.

Displacement will of course continue to shrink as the small engines produce more power and weight savings are always a goal.

The LS motors have been amazing, and will be for years to come but DI and overhead cams are the future.

[Mr. Wyndham]

Originally Posted by SC2150

The future is direct injection on the v8's for sure. The current LS block design is not strong enough for the higher compression the DI can run and for economy & power DI allows CR's over 11:1 without the issues of detonation. This is because the fuel is not introduced unitl just before the pistion reaches TDC on the compression stroke so there is no early fuel air mixture to ignite prematurely. I'm pretty sure the single cam push-rod design will go away as well as overhead cam designs are mor efficcient and stable at higher RPM's.

Displacement will of course continue to shrink as the small engines produce more power and weight savings are always a goal.

The LS motors have been amazing, and will be for years to come but DI and overhead cams are the future.

Much of what I've read has suggested the engine will remain pushrod due to superior weight and packaging. Though some are speculating it could feature an innovative cam-in-cam system to achieve comparable levels of VVT as seen in DOHC engines.

I wish we knew more!!!

[kencam]

They should bring the LT5 back!

[fielderLS3]

Originally Posted by Dragoneye

They've already invested nearly a billion dollars into the program, including plant retooling at multiple locations. It's real enough...they keep referring to a "revolutionary new combustion process".

That kind of investment is good news. That means they are planning on using small block V8s in large numbers for years to come, which to me suggests the V8 will still power the mainstream SS trim of the 6th gen Camaro, not just an expensive specialty trim like the ZL1.

[SC2150]

Originally Posted by Dragoneye

Much of what I've read has suggested the engine will remain pushrod due to superior weight and packaging. Though some are speculating it could feature an innovative cam-in-cam system to achieve comparable levels of VVT as seen in DOHC engines.

I wish we knew more!!!

That may be correct.....we need to see. The proof of how well the LS pushrod based engine can be is in how the corvette racing teams do so well against OHC based cars.

[DGthe3]

Originally Posted by meissen

Absolutely cracks me up that we're going to have an LT1 engine in a Camaro again...

That would make it the 3rd one, right? Early 70's, early/mid 90's, then mid/late 10's