I thought that I'd add some more information to the discussion of
the LS2, and LS7.
I just got a copy of "Pushrods for economical power:
The V16 engine of Cadillac's Sixteen concept car previews
future technology from General Motors that could see production
in upcoming vehicles such as the 2005 Chevrolet Corvette."
http://www.sae.org/servlets/productD...CD=1-111-9-117

It describes the XV16 in detail and clearly suggests that there
is a lot of the XV16 in the 2005 Corvette engine. Here are some
bullets of (some) things that may be new to people:

1) Bore and stroke = 105mm x 98mm
2) Bore to bore (centerline) = 111.8mm = 4.40in
3) Head design is very similar to LS6 (2V) - combustion chamber
design is unchanged but intake ports are a new (2004) "swirl design."
4) Crankshaft is billet 4340 steel.
5) Cylinder liners are cast iron (the block is aluminum).
6) Pistons are 4032 forged aluminum.
7) Connecting rods are forged 4340 steel.
8) Valves, retainers, and springs are titanium reducing weight 25%
permitting more aggressive and higher RPM valve operation.

OK, what does that say about the LS2? I bet 1) through 8) apply to the LS2
except the stroke. From the table below (columns are stroke, rows are bore,
and entries are total displacement. The LS1 and LS6 are bore = 99mm, stroke = 92mm),
I'd say bore = 105mm, stroke = 87mm. The LS7 may be 105 x 91, I still wonder
if the rods will be titanium.

Stroke|96mm | 97mm| 98mm| 99mm|100mm|101mm|102mm|103mm|104mm|105mm|106mm|107 mm => Bore
================================================== =======================================
86mm | 4979 | 5084 | 5189 | 5296 | 5403 | 5512 | 5621 | 5732 | 5844 | 5957 | 6071 | 6186
87mm | 5037 | 5143 | 5249 | 5357 | 5466 | 5576 | 5687 | 5799 | 5912 | 6026 | 6142 | 6258
88mm | 5095 | 5202 | 5310 | 5419 | 5529 | 5640 | 5752 | 5865 | 5980 | 6095 | 6212 | 6330
89mm | 5153 | 5261 | 5370 | 5480 | 5592 | 5704 | 5817 | 5932 | 6048 | 6165 | 6283 | 6402
90mm | 5211 | 5320 | 5430 | 5542 | 5654 | 5768 | 5883 | 5999 | 6116 | 6234 | 6353 | 6474
91mm | 5269 | 5379 | 5491 | 5603 | 5717 | 5832 | 5948 | 6065 | 6184 | 6303 | 6424 | 6546
92mm | 5327 | 5438 | 5551 | 5665 | 5780 | 5896 | 6014 | 6132 | 6252 | 6373 | 6495 | 6618
93mm | 5385 | 5498 | 5611 | 5727 | 5843 | 5960 | 6079 | 6199 | 6320 | 6442 | 6565 | 6690
94mm | 5443 | 5557 | 5672 | 5788 | 5906 | 6024 | 6144 | 6265 | 6388 | 6511 | 6636 | 6762
95mm | 5501 | 5616 | 5732 | 5850 | 5969 | 6089 | 6210 | 6332 | 6456 | 6580 | 6706 | 6833
96mm | 5558 | 5675 | 5793 | 5911 | 6031 | 6153 | 6275 | 6399 | 6524 | 6650 | 6777 | 6905
97mm | 5616 | 5734 | 5853 | 5973 | 6094 | 6217 | 6340 | 6465 | 6592 | 6719 | 6847 | 6977
98mm | 5674 | 5793 | 5913 | 6034 | 6157 | 6281 | 6406 | 6532 | 6659 | 6788 | 6918 | 7049

Gasoline (Spark-Ignition) Direct Injection
==========================================

If you want to bone up on direct-injection for spark
ignition gasoline engine, here are some things to look
at. I mention this because both patent drawings of GM,
3V engines appear to be direct injection engines.
Here's a slide show done by the Australian company
ORBITAL.
http://www.orbeng.com.au/orbital/orb...DF/00_HAMB.PDF

Here's a more technical version of the slideshow.
http://www.orbeng.com.au/orbital/orb...02-01-0705.pdf

This paper describes the application of direct injection into
both a GM DOHC 2.2L, 4V engine as well as a GM GenIII, 5.3L, 2V, V8.
There are some nice pictures of the combustion chambers of
both engines. What is not included is any discussion of the
GM 4.3L, dual camshaft, 3V, V8 called the XV8.
http://www.orbeng.com.au/orbital/orbitalTechnology/PDF/aachen01.pdf`

That (XV8) is contained in
http://www.sae.org/servlets/productD...D=2003-01-0545

It has a nice picture of the XV8 combustion chamber layout and
I think that this is essentially what the LS7 combustion chamber
looks like although probably scaled up a bit. The recent GM slide
http://www.media.holden.com.au/divis..._injection.pdf

seems to be based on some of these papers.

Quick comment. If you want to get the SAE papers, call up your
local large university and see if the engineering library has
a "subscription" to SAE for their papers. If so, just download
them for free (except paper costs).

I'm not going to venture much in the way of analysis on all
of this except these few things. The true potential of gasoline
direct injection is intimately tied to the sulphur content of
gasoline, I think that at least California will be at 30 parts
per million by 2005. These GM papers want less than 10 ppm to
meet future emissions requirements. The second thing is that the
XV8 and the GenIV, 3V engines seem like direct injection is a
fundamental part of their design. Although DI gasoline seems marginally
ready to meet emissions requirements, it sure looks like the LS7
is a DI engine.

 

Nice research...You've got a calling as a para-legal

 

I believe that if GM wants the combustion chamber to maintain high swirl and tumble they will need to keep the bore size near its current level. That is assuming swirl will stay at the level of the current design. If they have been able to up swirl considerably they may decide to move to a larger bore. I am interested in finding out.

I'd be willing to bet 4,7,and 8 will not apply to the LS2.

This is what I think:

4)The billet crank was almost certainly used because of the tremendous length of the V-16 crank. This would not be neccessary for durability or feasible from a financial stand point for a production V-8

7)Powdered metal connecting are cheaper to produce than traditional forged rods and have near the same strength. I think powdered is what they will use mainly due to cost.

8)Ti parts were almost certainly used to offset the weight of the additional 16 valves over a V-8. I believe GM will choose ovate wire "beehive" springs along with steel retainers and valves.


As for Ti rods. I do not think this will happen anytime soon at GM. Due to Ti's extreme notch sensitivity it is NOT well suited for use on an assembly line. I believe the NSX motors built by Honda are assembled in a niche line of sorts similar to the Cobra motors for this very reason.
Other factors that I can think of are cost and decreased strength.

Sulfur content in our fuels is a major reason we do not see performance diesels in the states. I suspect when the content drops we will begin to see more performance diesels and D.I. gasoline engines.

Thank you for the informationn J-Rod.If you see any faults in my ideas or have additional information please reply.

 

Will be interesting to see how DFI works out with these new engines!

 

J-rod didn't write that thread!! He ripped it off from the Corvette Forum.
I wrote it. That's pretty classless J-rod. Any more threads here that I
might recognize ???

 

Usually that is how information spreads through car forums of the same interests/platform. Get over it

 

Thanks for the information J rod..

Very cool..

JB

 

I never claimed to have written that thread. I think my only comments in the thread are:

I thought that I'd add some more information to the discussion of
the LS2, and LS7.

Then I pasted in the information from your thread. In some cases when I post I put in a line =======================================, and then post in the quotation, and in some cases I post a link to the thread. It all depends on if I feel like going back and copying the link, etc... I'll admit that sometimes I'm just lazy and don't feel like messing with it. So, shoot me...


I"m sorry you consider it "classless" to have cut and pasted a thread I found on another site. I never claimed it as some sort of original work like "yeah it took me a long time to find all that stuff". Even if there was a citation I don't think it would work any more since CF since changed software. If you have a good link to the thread, post it up...

Additionally, why are you dragging up a thread that is 10 months old and that no one has looking at since 2003???

Look, I appreciate all the information that you have posted in the C6 section. You obviously spend a lot of time researching patent stuff. I find threads all the time that I post from one site to the other. I posted one yesterday that I found about LS2 part numbers.

If its going to get your shorts all in a knot I will ensure that any time I cite anything remotely connected to you with your name and a link to your thread if it will make you feel better.

I do find it humorous that you registered on here just to post that. But, since you are here, feel free to post any more info like that oon this site yourself. I think everyone would appreciate your valuable technical input. You certainly have a knack for finding interesting technical documents and information. I think folks on this site would appreciate your efforts.

 

 

According to John Meaney, developer of "Big Stuff 3", he and his brothers forward engineered Big Stuff to work with the LS2 platform.

 

Thats cool to know...