I assume that I will get whatever happens to be around. Is there any way to make sure that I get a 2009? Are they avilable?

It's important since there are suppose to be significant improvements in 2009.

Thanks

 

i assume you would get an 09 but like you im not sure. i would talk to someone at GM to see if they can make sure you get what you want.

 

and what were those improvements?

 

I would like to hear what changed also. I show the 2009 replacement engines as being a carryover from 2008. The bare blocks are only available through GMPP and they are not showing a number change at this time.

 

Improvements? I am also intirested in this... Are they making more power out of them? Or are they just fine tuning them?

 

I have heard of no changes to the LS3 since its introduction in 08. GM did change some parameters in the tune that could produce slightly more power than the 08's out of the box.

 

I believe the block casting is slightly different which they claim is significant:

GM version

 

Honestly, it seems like they are just rehashing the original changes that were made in the creation of the LS3, while noting that the new Camaro will get many of the upgrades the LS3 underwent in its transformation into the LS9.

 

I don't have the improvements that gm has claimed handy but they are using the same blocks for the LS9. Since it required improvements (strength and quality) to reliably handle 638 hp on their premier corvette, those improvements have been made to all LS3 blocks in 2009.

I had heard that the quality of the prior LS3 blocks have been suspect (the LS2's have been better).

 

I thought that was L92 blocks. While the casting is the same for the LS3, I "thought" I read they were produced at different foundries with different levels for QC.

 

There is a New or second generation LS3 block as used on the LS9.
It does have a temp part #xxxxx982 and is not yet available. There is a note that some of the previously compatible parts will not interchange so at this point you do not want the New version.

The info is as of 10/22/08

 

The LS3 heads have changed . and springs and valves more then 3 times, since the LS3 heads first came out.

 

The blocks were not exactly stiff enough. I have a source that says in the right conditions the block would twist enough to start side-loading pistons and cause failure. In his testing the LS3 would not last nearly as long as the LS2 for this very reason (testing was under extreme conditions). The difference was in the block and its rigidity. The LS9 block is being used in the LS3s in the future to prevent this problem. I'm not sure why GM let that one slip through the cracks.

 

What revision to the LS9 block would prevent twisting?

 

If the block changed, GM will have a new part number. Go to a parts guy when the new Camaro comes out and ask them for the replacement block specific for that car. It will have a different number if it changed.

-Geoff

 

The difference is in how the block is casted . GM is using a "rotocast" process which uses centrifugal force to create a denser casting . This process is supposed to be applied to all aluminum blocks .

 

The heads use the rotocasting method to reduce porosity, a very recent change. No evidence of blocks being rotocast yet. Took long enough to get the heads up and running with rotocasting.

The LS9 blocks are different in that they have oil jet feeds to spray the undersides of the piston crowns for cooling, as well as durability improvements.

The use of increased radii (from 3mm to 8mm) in the hone overtravel area started around the last quarter of 07, and then went to 10mm for LS9, as did the LS7 style radius on the bay to bay breathing slot edges: durability improvement as well as a stiffness improvement, as the increased radii improve fatigue strength as well as leave a little more material due to the inside radius increase in the hone overtravel area.

Cheers.

 

I've also seen the info. describing the structure of the block being more durable for factory supercharged use. We're going to see a gradual transistion to the LS9 block over the year as current LS3 block inventory runs out. Think 2002 F-bod with LS6 blocks and LS6 intakes, also, same scenario if you buy a set of LS1 lifters these days they are the same as the LS7s. When GM comes out with a better version, part numbers just supercede. I would think the only "safe" way to confirm that you have a LS9 block would be to grab a ZR1 vin and check the part number for a replacement block against a early 08 standard C6. GM part depts. can begin to have access to replacement parts as soon as month after the vehicles are introduced to market. Who knows if that will hold true with ZR1 parts, but if so I would imagine that you may have some luck soon. SDPC may be able to provide more info. here and may have quicker access than others.

 

Thanks, I called the tech line at SDPC and the guy claims over the last 90 days or so they have been seeing the improvements incorporated in the LS3 blocks. I don't know how reliable the information is. I wonder if parts gets their inventory (at least at the gm level) from the production inventory. I was just thinking that a lot of vettes have been produced in 2009 so they should be into the new stuff at least at GM's level.

 

FYI

From - http://www.corvetteactioncenter.com/..._pursuit1.html

The aluminum block, or "cylinder case", used in the LS9 is a relative of the unit used in the '08 Vette's LS3 and in the 6.2-liter, L92 GM puts in Cadillac Escalades and GMC Yukons, but it has some key differences.

First, there is a further strengthening of the main bearing webs by once again redesigning their windows. These windows allow the bay-to-bay breathing and oil windage control which helps lessen parasitic power loss and reduce crankcase oil windage.

GM Powertrain did a great deal of finite element analysis (FEA) work in search of a reliability/durability margin at the projected 620-hp similar to what the LS3 has with 430-hp. This research indicated that the windows in both the LS9 case's number-two and -four webs could be further strengthened by reshaping them in a manner that altered the stress concentration in each web. This reshaping, also, resulted in a slight increase in their areas. "Those windows are larger and have a non-symmetrical shape," Ron Meegan told the CAC. "When we made them larger, we were able to move the edge of the opening to a thicker portion of the bulkhead and that is where the strength improvement comes from. We were able to get to this sweet spot using finite element analysis. We incrementally increased the size of the window until we reached the maximum safety factor. If we go larger than this, the safety factor begins to decrease because the size of the hole overrides improvement from the increasing thickness of the bulkhead."

The window in #3, which, previously, was larger than those in the two and four webs, because the center web is the least stressed, was slightly reduced in area to match the profile and area of the other two. Testing proved that slight area decrease did not affect bay-to-bay breathing or crankcase windage.

The net result of this latest round of block window alterations was another, 18% increase in strength of the webs and a 36% increase, total, at the LS9's power level., beyond the first Gen 4 block, the LS2. This change is not specific to the LS9 and will be implemented for all V8 aluminum blocks starting in MY09.

Second, the main bearing caps are forged steel, like those those in the LS7, rather than sintered, powdered steel units in other Gen 3/4 engines, and they are aligned with dowel pins, another LS7/LS9 exclusive.

3) The crankcase is fitted with nozzles which aim an oil spray on the bottom of each piston for enhanced piston cooling and there is an interesting side benefit of them. "The oil squirters," Ron Meegan told the CAC, "are targeted to spray on the un-derside of the piston at TDC. As the piston moves up and down the bore, some of the oil gets deposited on the bore and the (acoustic insulating) effect of additional oil on the bore provides a noise benefit." These squirters screw into small passages drilled into the main bearing oil galley, 4) the block is threaded for larger, 12-mm head bolts and 5) it is bored and honed with deck plates bolted in place. Other aspects of the LS9 block carry over from the LS3, about which additional details can be found in the CAC's LS3 article.

Like all Gen 4 aluminum blocks, the units for the supercharged (SC) Small-Blocks are cast by Nemak in Monterey, Mexico, however, the LS9 case is finish-machined by Albert Weber GmbH. Initially the work was done in the company's plant in Germany, but that task is soon to be moved to its manufacturing facility in Charleston, South Carolina.