Turn your LS2/LS3 into a Stage 3 LS7-LSX

[Indydriver]

Well, if I blow up my soon-to-be unwarranted '14 LS3, it's nice to know options like this exist. Of course, we all want to see the output numbers. Looks like a five figure deal to me.

[SSeniorMoment]

What are the advantages of doing this vs getting a wet sump LS7?

[mikeyg36]

PMd with no response back.

[MikeOD]

Originally Posted by Livernois Motorsports

This allows absolute precision and ensures the block is held to within just +/- .0001 to the specification.

0.0001" true position of every bore??? Including parallelism of the bores to each other, perpendicularity of the bores in bank 1 to bank 2, perpendicularity of the bores to the crank shaft, deviation of the bore centerlines to the crank centerline, deviation of the bore centerlines in each bank to each other, distance between bore centerlines, offset between bore centerlines in opposing banks, squareness of the deck surfaces to the bore centerlines, flatness of the deck surfaces, parallelism of the deck surfaces to the crank centerline??? All relative to one "block" datum???

[Andy@Livernois]

Originally Posted by 62nalide

Sounds nice!
I am considering your mini stroker 390 short block next spring!

That's great! It's a great balance of durability, increased displacement, and value.

Originally Posted by Irnwkrkev

Do the LSX-LS7 heads have a better reputation for valve guide wear then the regular production castings? Are the intake valves still titanium?

Would also like some more info on your mini stroker. Is it an offset ground factory crank with honda rods? What kind of compression ratios are available with it? Thanks!

The LSX-LS7 heads are a better casting material, but since they are not nearly as common the sample rate is much lower. Also, most of the LSX head builds we do have upgraded valves, so this also skews the ability to answer this.

The mini stroker is a custom machined steel crank, but definitely not a Honda-rod journal, that would not be something we recommend, we still use a production (well, of course upgraded) chevy bearing for our builds.

Originally Posted by grocerygetter

So I could do this to a ls6 block?

We do ahve an option for an LS1 block, but we always prefer the LS2/LS3 blocks as they are much stronger.

Originally Posted by flashtech

What is the hp rating at the crank on this setup?

We rate these shortblocks to 1200hp

Originally Posted by Sapper12b

Curious to see the HP and TQ numbers on a build like this ?

We have had numerous builds with them already as we have been sleeving these engines for many years.

Originally Posted by Indydriver

Well, if I blow up my soon-to-be unwarranted '14 LS3, it's nice to know options like this exist. Of course, we all want to see the output numbers. Looks like a five figure deal to me.

This specific build shown here is a Naturdally aspirated setup built to mimic our stage 3 ZO6 package. That package makes over 700hp at the flywheel. He wanted to have it built to handle well over 300hp worth of nitrous as well.

Originally Posted by SSeniorMoment

What are the advantages of doing this vs getting a wet sump LS7?

The LS7 block is actually one of the weakest blocks made, making it not suitable for high HP builds.

Originally Posted by mikeyg36

PMd with no response back.

I apologize for that, look for my PM shortly

Originally Posted by MikeOD

0.0001" true position of every bore??? Including parallelism of the bores to each other, perpendicularity of the bores in bank 1 to bank 2, perpendicularity of the bores to the crank shaft, deviation of the bore centerlines to the crank centerline, deviation of the bore centerlines in each bank to each other, distance between bore centerlines, offset between bore centerlines in opposing banks, squareness of the deck surfaces to the bore centerlines, flatness of the deck surfaces, parallelism of the deck surfaces to the crank centerline??? All relative to one "block" datum???

I do not have all of the technical data, but I will get someone from our engine team to contact you with the information requested.

[MikeOD]

Originally Posted by Andy@Livernois

I do not have all of the technical data, but I will get someone from our engine team to contact you with the information requested.

Nobody needs to contact me. Please don't be offended, but I'm pointing out that you should not make a statement like this. Just because the control on the machine reads to that resolution does not mean it's that accurate. Without inspection equipment that can measure to one more zero after the decimal, which would cost a LOT of money, it's actually very bad practice to make a statement like that.

I'd bet, and it's not a bad thing, that your machined blocks overall hold +/-0.005"...if you have machinery and talent that can hold an entire block, all machined features, to 0.0001" tolerance (+/-0.00005"), they should be in a secret government facility...space station parts are not held to a number like that because it's next to impossible. Generally only the tightest tolerance bores and ground surfaces are/can be held that tight on a diameter, and maybe to 0.001" true position to the parts datum...and it takes some of the best machines Japan, Switzerland and Germany have to offer to get there.

[IMJ]

Originally Posted by Livernois Motorsports

Apparently Skynet and the T-1000 are being produced at Livernois. Color me curious. PM Sent!

[Joshua nuzzo]

Very nice work guys keep it up!!!

[Livernois Motorsports]

Sorry if there was any confusion in regards to the accuracy and tolerances held during the machining process. It probably makes more sense to expand much further on the above tolerances and specifications used, along with the machine tolerances as well as machining methodology.

The best starting point is probably the actual specifications themselves and how they come into play in regards to machine work and build tolerances.

The specifications that are used for every engine job that Livernois works on are based on a combination of things. The starting point in most cases is always the reference data that comes from the OEM for that specific engine. This data is used as a reference point to base our specifications around.

As most of you are probably familiar with, modern day OEM engines are produced using a system of "select-fitting" parts. This system allows for best combination of cost vs. precision. Every block machined will have a code attached to that block. The same goes for the crankshaft, the pistons, the rods, etc. The bearings usually come in 3 grades, each being a different thickness, and sometimes the pistons come in grades as well.

These codes tell the assembler which bearing or part goes together by calling out the matching component on a chart. A matches A, etc. This system allows for the OEM to hold a decent tolerance for all the various components that fit together in the engine. While this system works very well at the OEM level, it's not the most desirable thing for a performance engine. Even with this select fit system the tolerance for a clearance can be something like +/- .0008, or a spread of .0016 across the range. That means a bearing as tight as .001 and as loose as .0026 clearance is considered within range.

While this is perfectly satisfactory for a stock engine, and will work even for most performance engines, we're trying to build the best possible engine for a given application. So we use much tighter tolerances than the factory does.With that said, the starting point in most cases for the specifications we use will almost always be derived from the OEM blueprint, as this is what the OEM targeted as the specification, and this is what the block/component will be machined too. So we base our starting point around that specification. As listed above in most cases that specification is going to have it's own tolerance from the OEM. We take that specification and then modify the tolerance that the OEM manufacturer used to better fall in line with the application requirements.

So as an example, +/- .0008 OEM tolerance would be changed to +/- .0002 to match the tolerance of the machine. Though we can somewhat cheat the machine tolerance a little tighter by utilizing two forms of measurement. The machine itself uses a Marposs probing system. The probe itself is accurate to around .00005 and is used for setting up and indicating the block in the fixture. Though the probe is highly accurate we also utilize a .0001 dial test indicator as a secondary form of measurement and verification. This allows better repeatability from known datum points on the machine in reference to the block.

The block is fixtured into the machine and then referenced against a couple of datum points on the block. The main reference is crankshaft centerline as well as block datum reference (usually located on the pan rail). From there we can reference and record the crankshaft centerline in relation to the camshaft position, and from there bore perpendicularity to the crankshaft, bore centerlines, bore offset, etc. These are all referenced as multiple x, y, z coordinates in relation to the reference. The deck can also be referenced and recorded, both in the form of probing, which records 6 points on the deck surface (front inner/outer, middle inner/outer and rear inner/outer), and also by using the test indicator to sweep the deck. This allows for reference of the deck for square, flatness, parallelism, etc.

All of these initial measurements are taken by the operator and recorded in the software of the controller. From there the operator can assess and verfiy all the measurements with a secondary form of measurement to ensure accuracy. Once all the data is in hand the machine work itself can start and then be checked following it's completion.

A critical component in this entire system working as it's supposed to is that all the gauges and tools as well as the machine are correctly calibrated and routinely checked. As most are probably aware, the output of the work is only as good as the operator and the tools that are used. Tools that are not checked regularly allows for deviations. This requires that every tool is checked. This means that the micrometers that are used to set the bore gauges are checked with standards, and that those standards are sent out to a metrology lab to be verified and inspected. The probing system has to be checked with a indicator as well to ensure that it's accurate. Every last tool must be checked throughout the sequence, otherwise you allow for error.

Another aspect that ties in with maintaining accuracy is the environmental controls in place to ensure everything being measured at the same relative temperature. The measurements are taken at a specified temp in a climate controlled environment to ensure that all measurements are being recorded at an equal temperature.

It requires a very high level of detail to maintain this criteria, but it also ensures that the engines we produce are built to very exacting tolerances. The application determines the specifications and tolerances. One of the most important area's in regards to machine tolerances for determining engine performance is bore geometry and cylinder finish. Ensuring that we're +/- .0001 for piston to wall clearance, taper, etc. takes extra work and a skilled operator with a machine he's very familiar with.

Overall the level of accuracy to which we hold ourselves in a lot of cases is probably overkill. Most engines will work with a +/- .0005 or even +/- .001 tolerance. That doesn't mean they will perform optimally though. Trying to be as precise as we can within the envelope we have to work helps to ensure the best possible product. The reality of the situation is that no measurement system can measure a component to accurately simulate the dynamic conditions that occur when the engine is running. While we may work to hold a +/- .0001 tolerance for certain applications, when the engine is running it could care less about that last .0001. At high speed pistons look like they're made of rubber and deflect beyond that .0001. Bores under load balloon and shift more than .0001. The block itself twists and distorts more than .0001 under higher load and power. Measuring all of these dimensions in a static condition is about as accurate as you can get. From there you add (or subtract) and modify clearances, dimensions, geometry to best account for the changes that will take place when the engine is running under load and at temperature. This is where an extensive knowledge-base of engines, testing, development come into play as it gives you a lot of information to utilize for making these adjustments.

Yes, we're probably over-killing it in regards to the measurements and level of accuracy we hold ourselves too. But we pride ourselves on striving for perfection.

[Irnwkrkev]

^ Well stated