Well heck, the increase from the base C6 to C7 was so much, this is pretty likely.
Oh wait... :rofl:
S.

That's all great but none of it invalidates the fact that the LS7 is not a true 427 in the technical sense, nor fits in the traditional big block set of guidelines. Getting big block displacement out of small block architecture means thin walls. This is quite easy to prove.

You have proven my point more than you can think. You bring in faith yet you lay your faith on a racing block and aftermarket companies. Not to long ago you were afraid your LS7 would blow up, now you seem to have godly love for the thing. :crazy:

I don't care what anyone says, the "427" will forevermore be a marketing ploy for Corvette/GM, in whatever engine form it takes. You can look at that as a bad thing or a good thing, depending on your perspective.

You can bet that the Z28, Chevy SS, etc, will have 427 badges somewhere from the factory or from the aftermarket. And they will bleed that moniker (like LT1, L88, Stingray, etc) for all it is worth. To think otherwise is just foolish.

What I don't get is how they plan to move forward with what is clearly a flawed engine. With all the LS7 Corvette owners so obviously POed, you'd think they wouldn't attempt to stick it into all these other cars. I, for one, am really glad they are apparently keeping it out of the C7. Who needs that negativity for a new generation of Corvette?

Can never fault a man for purchasing a nice car he likes. Enjoy the C6Z :)

-Alex

Ah, grasshopper, how you delight in being wrong. "It is not a true 427 in the technical sense." What does that mean, because it does not have a carb and points based distributor? :crazy2: It has a DISPLACEMENT of 427 plus a few decimal points. Is the new Boss 302 not really a 302 because it uses updated technology? Is the 392 Hemi not a Hemi because it is not a 426? Are you anti-technology? Are you the "Official Decider By Appointment" of such things? How special that must be for you. Have you writtne to these companies yet to correct their decisions concerning how they classify their products? :toetap:

Thin walls have not been a problem with the LS7, as I described how it was designed in conjunction with Katech, which I guess to you is just some run of the mill aftermarket company...:lol: I have a lot of that back-alley company's stuff in my car - God, what was I thinking? :crazy:

I am so surprised it took you so long to drag the "blow-up" thing out - getting a bit desparate, it seems.

So rather than telling me what I think, or why I did what I did, suppose we try this: some more facts, and my explanation of MY own actions.

GM has a long and not to glorious history when it comes to Vette engine issues. A small, partial list follows. Let's see:

1. Original LT1 - major problems with poor design and placement of Opti-Spark ignition, a well known problem that could easily strand the owner

2. 2001 Z06 - Significant problems with oil consumption, ring pack issues

3. C5 Z06's - Abnormally high occurence of valve spring breakage

4. C6 Z06's - Sporadic problems with quality of head manufacture (poor quality control) NOT design BTW, some ZR1's displaying same quality issues

I chose to upgrade my heads since I tend to exercise the car strenuously at times and I wanted to ensure that I headed off a possible GM quality problem before it had an opportunity to do more damage.

How sad for you that you can only think of detrimental things to say about the LS7, since it appears your low level of confidence seems to demand you attack it.

Now, as I said before, I have NOT said one negative thing about the LT1 in C7. But come closer, and I'll tell ya little secret. SSHHH! You see, the LT1 is bringing together a lot of new technology in this engine: DI, DoD, AFM, Variable Timing, etc. No amount of simulation can fully duplicate how people will use these engines in the real world over time. Given GM's long term recurring history of not quite getting it right right out of the door (and this is true for many manufacturers), I would not be surprised if "teething problems" crop up. Remember the Boeing "DreamLiner." Do you have any concept of how much engineering and super computer time went into that plane? And, in the real world, it didn't take long for some serious problems to crop up.

Think about it... And please write back soon, I so enjoy your curious logic!

Yes, of course you don't care - that makes it easy for you to forward a position that takes no research or logic to arrive at. And while we are on that subject, could it just possibly be that dragging the time-honored "Stingray" name out of the GM history vaults, where it was associated with some of the most famous Vettes in history was...was.... wait for it.... could be a MARKETING PLOY?

Thanks for making it so easy! :lol:

"That's all great but none of it invalidates the fact that the LS7 is not a true 427 in the technical sense, nor fits in the traditional big block set of guidelines. Getting big block displacement out of small block architecture means thin walls. This is quite easy to prove."

LOL wut? Not a true 427? So how much cubic inch displacement does an LS7 have?

-Alex

Excellent point!:thumbs: I mentioned retro once and got lambasted, but the famous "Stingray" name is being slighted IMO.

I think to be exact 427.7 CI

"I think to be exact 427.7 CI"

That looks like a true 427 to me then lol.

-Alex

:lolg:OMFG, what clowns we have here. Maybe you and Big oughta read my statement again before opening your yap. :lolg:

Wow, guess the you really have earned your rep for the cheap shots, going right to personal attacks when someone dares to present any logic...:lol: Just doesn't work for me, so please don't waste your time.

Ox boy, you and your ego have a nice holiday, ok? And try to calm down.....:crazy:

Oh, I see. Who jumped on me first?:toetap:

You are about as irritating as people get, truly fell sorry for everyone that is in your inner circle.

First of all don't afford yourself the comfort to call people names, just because we're on a public forum it doesn't mean it's not irritating.

Secondly, you need to cut the garbage in your posts. I don't care how much forum knowledge you have accumulated and frankly it's irrelevant to my posts and yours. Congrats, you are a 3rd rate bench racing historian. Now try to compose a concise statement for a change. So next time you feel like schooling someone on an off topic subject, skip it.

Third, everyone knows by now that you would jump off a bridge if Katech recommended it. Your logic and scientific responses are nothing more than hearsay. Buying expensive things does not make you an expert.

Point 1 427 technically means 427 cubic inches of displacement (CID). Judging by the stats released by GM the LS7 is a 428 cubic inch engine. As accurately stated by Car and Driver: "Much of the 427 convertible’s equipment is available on the mid-level Grand Sport roadster, but the one thing that defines the Z06—its 428-cubic-inch LS7 V-8—is the 427’s main draw. (Chevy fudges the displacement as an homage to the old big-block engine—feel free to call it, more accurately, the 428.) "

Point 2 It does matter that the 427/428 cubic inches of displacement are generated by boring out the block, not by designing new slightly larger block. Two problems with it, reduced block strength, reduced cooling capacity. Here is CD on that: "The engine has a new designation—LS9—but it shares the LS3 aluminum block used in the standard Corvette, with a 4.06-inch bore and a 3.62-inch stroke. Chevy chose the 6.2-liter rather than the 7.0-liter LS7 that powers the Z06 for durability reasons. The cylinder walls in the LS7 are too thin for comfort with forced induction. "

Point 3 Both the LS7 and the LS3 have identical specification in terms of sleeve materials and build techniques. Namely both blocks are made out of the same cast A356-T6 aluminum alloy and both are built by pressing in iron cylinder liners. There is no magic GM implemented on the LS7 to prevent the two problems stated in point 2 above. See for example Ford's patented plasma-transferred wire arc technology implemented in the GT500 and purchased by Nissan for the GTR: http://jalopnik.com/5467038/the-ford...he-nissan-gt+r. But GM DID do very well on the LT1 block strength wise, namely they have used the LS9 formula almost entirely on this "base" engine which to me signals that the LT1 is much more capable than the LS3, and certainly more capable than the LS7 in terms of block strength and cooling. From GM inside news: " Where the current model has the iron liners pressed into the block, allowing the top to protrude ever so slightly from the top of the deck, the new design superheats the liner and allows the aluminum to form around it, leaving a clean and flush surface to mount the heads to. This also solves the issue that GM was running into of not totally surrounding the iron sleeves with engine material. Now that the engine is cast around the iron sleeves, this helps strengthen the engine and allow it to take more abuse, as well as pressure."

In addition to the thicker block, and the better method for setting the sleeves in the block the LT1 is going to benefit from reduced temperatures due to the implementation of piston oil spray jets, direct injection, and will be more resistant to faults in general through advances in bearing materials.

Point 4 This is my last and can be an all inclusive point/explanation of why 427/428 CID doesn't mean ****. Imagine we have CID plotted on the horizontal axis and something relevant to engine performance on the vertical axis. If we were to observe a kink, hump, discontinuity, cliff what have you right at that value in a favorable direction then we could conclude, logically, that there is something special about that CID. I have personally implemented many models to capture this behavior in empirical distributions.

So here is a challenge for you:
Find me such an empirical anomaly where one, just ONE aspect of engine performance is unusually high at a CID of 427.

I'll use one of the leading statistical methodologies for quantifying, documenting, and testing for significance to verify your finding.

Good luck!

According to every source I found, GM or not, there is a consistant stating of 427.7cubic inches.

To me that means 427.7 which does not equal 428.

SBC and a stick, I am not going to start an e-battle with you but, just pointing out that you typed "it's not a true 427" when clearly it is. The displacement is not 428.0+. It's in between 426.99 and 428.00. Just sayin.

-Alex

The way we round off engine displacements has been heavily influenced by racing regulations and displacement based taxes throughout the world (but not in US). Car manufacturers are global producers so these rules are more or less binding for the entire fleet. If you look at the data, a car manufacturer cannot get away with a 2.999 liter engine claiming that it is a 2.0, but rather you'll find all of them are just under, and 1.95 or something of that sort.

Rounding numbers in general dictates rounding up. Imagine for a second that 427 and 428 are not CID but distances. Say Paris is 427 units away from something and New York is 428 units away from that same something. If you had to say which city you would most likely be a resident of, assuming concentric equal radius cities, 427.7 is closer to New York by exactly .2 units. Why claim Paris in this case?

In that technical since, I can see your point. In my literal since, I will just continue calling it a 427. So I guess we can respectfully agree to disagree :)

-Alex

No offense, but you really need to bone up on engine history and modern technology. 427 does not automatically mean big-block. If you are looking for traditional naming, GM has offered an aluminum small-block racing engine since at least the 70's, the SBC, so there is your traditional o-fficial precedent. Second, the 427 label applies as long as the motor displaces at least that amount, which it does. Third, the displacement is not achieved by thinner walls, nor is an LS-7 "bored out" to get there. The block is cast and a liner added. Most of the additional displacement is achieved with a longer stroke. Yes, the material is a bit thinner, but that is not an issue with modern alloys (unlike iron blocks, where it was indeed a concern). There has never been a failure of the LS7 block that I am aware of, and the same can be said of the Katech racing engine. Finally, the thinner the material, the more effective the heat transfer and cooling, not the other way around.

The LS7 is far more than a gimmick and we are many decades beyond the iron blocks of yesteryear. We even have electronic ignition nowadays...

The wicked COPO Camaro uses a stock block 427 7L LS7 with 13.5:1 CR and a 7500 RPM redline and a very hot cam. Aluminum, not cast iron. GM seems to feel that the stock 427 block is pretty strong. Not to mention that the C6R uses the LS7 block with a slightly smaller bore and very short stroke for 5.5L.

The other two engines are cast iron block LSX 5.3L engines with a short stroke and a blower on top. They didn't use an aluminum block LS3/LS9 for those applications.

Before I begin to address your string of azzumptions, first a big shout out to Forum Member "Dominic" who gets it. Unfortunately, as he and others have learned with dealing with your bunch, you don't. Congrats on being the latest embodiment of that old saying regarding those who make azzumptions, and what that makes them.

And, oh, don't worry too much about my social life, I shared your juvenile nonsense with some of our friends who were over to the house yesterday for our holiday cook-out, and we had a good laugh. My wife (the lady having dinner with me in my avatar) asked me if you were a little "mongolito." English is her second language...

Also, do you really want to cast aspersions on someone because they may seek some advice from highly respected Forum Vendor, KATECH? Perhaps yet another indication of your judgement?

Azzumption Number 1 - 3rd rate bench racing history knowledge. Hmm, well I have OWNED and competed with several of the cars on my original list, including: '92 LT1, '02 Z06, and '10 Z06, among the 9 vettes I have owned. I have been competing in track events since the 90's, so I speak from first hand experience.

Azzumption Number 2 - Everyone knows I would jump off of a bridge for Katech. Actually, no. You see, in my latest build, I do have some Katech parts such as their Torquer 110 cam, but I had a disagreement over their approach to the heads. I worked directly with Richard, the owner of WCCH, to come up with the specs for the heads that are now on my car. I worked with Randy over at DRM re suspension bits, Jim Hall re my cold air intake and DRED hood. My longtime friends over at ECS did the final work and tune. You truly are a putz...:lol:

Azzumption Number 3- Your rather bizarre fixation with 427 or 428. Mostly already been previously addressed, but you really need to write to the manufacturer of the engine and demand that they re-name their own product. And don't forget those other letters to Ford, Chrysler, etc. While you are at it, perhaps you should chastise them for re-utilizing "StingRay" for the C7, since the new car has absolutely zero connection with the original. Hmm, but something tells me you won't write that letter. :lol: Yes, how special you are to see this and to ensure they fix their mistakes....:crazy2:

Azzumption Number 4 - Thanks for copying a bunch of easily obtained tech specs - not sure they have anything to do with LS7 cooling issues. Amazing, simply amazing that this engine served as the basis for C6R power to win ALMs Class championships year after year. Even more amazing that neither I with the two C6 Zs I had, or many people I know who track their Zs have had cylinder wall problems or overheating. These are not inherent flaws, and of course why you bring in the totally irrelevant reference to supercharging an engine designed as N/A is of course another example of your nebulous thought procesess.

Again, all this spewed effluvia from you and I have not said one negative thing about the LT1. There is nothing to say. It has not been released to the consumer and therefore has zero real world track record. It has not been used in competition, therefore has a zero track record. After it has been around for a while, we will know how the LT1 measures up.

How sad for you that you feel driven to denigrate the LS7 in a pitiful attempt to defend something else.

On the positive side, thanks yet again, for making this so easy!! :yesnod:

Well said.:iagree: