Owners of 416 stroked LS3's...

[Good2go]

Lots of informative posts, thanks for all the responses!

[FloMoCamaro]

What is a safe horsepower limit on an alum ls3 forged 416/418?

[jsharp]

Most ive read 700-900 crank is max so 700-800 should be good?

[JETG]

Originally Posted by Jason 98 TA

4.070" is a great option if you do not have the ability to check & correct machining issues within the block. In a typical machine shop your basically having to bore & hone whatever the block is & hope it's correctly machined from GM. I'm here to tell you often they are no where close from GM.

At TSP we use the cnc machine to properly digitize the block & then study the data to determine what that specific block is best suited for. In other words we might have 5-6 different LS3 blocks lined up of which some are needing to go 4.070" bore, and some need to be 4.080" bore. The first block might have sleeves that aren't aligned correctly & therefore might be better at 4.080". If the block isn't correctly machined from GM most machine shops can't measure this & just bore & hone in the same incorrect position. We use the cnc machine to correct these factory machining issues.

A perfect example is I'm currently machining a brand new LS7 block for a customers 427 stroker. This block in particular was mis-machined by approximately .003-.004" in the one direction & almost .010" in another direction. That far off might be in GM spec, but isn't correct to the blueprint. It all depends if you want a close enough engine or a completely blueprinted engine.

In other words thanks to the cnc machining center we are able to completely "blueprint" a engine block like no other LS company in the country.

Jason

What is the cost of your short blocks, 416 and 427 ??? LS3

[CC Performance]

Originally Posted by FloMoCamaro

What is a safe horsepower limit on an alum ls3 forged 416/418?

It's subjective really. There are so many variables. Are you taking about just the aluminum block or the short-block?
We've seen guys on here push the factory engines to 800+ rwhp so that thats like 900+ at the crank.. then you have longevity.. how long at that power level do you want it to last

Bottom line is you have aluminum which is a soft metal and it's own expansion rate mixed with steel which has its own expansion rate... then you have that crank swinging ... it all comes into play.

Wheel to Wheel used to have a 1200 hp LS2.. they offered using good internals...
If I was looking to make that or more I'd use and RHS block or more likely iron. And again its not to say that you cant get aluminum/LS3 to live past that... Its just my personal choice at those power levels

[Jason 98 TA]

No we do that on every block. We brought all our short-block machining in house & purchased the top of the line equipment to make sure we built the ultimate short-block for our customers. Go to any machine shop in the country & then come here for a tour. If your not sold 3 times over I'd be completely stunned!

[Jason 98 TA]

Here's what makes a TSP short-block different from other engines on the market.

We use a complete CNC machine to digitize & machine the blocks. This way, we can closely inspect a block & put it on factory blueprint specs. A typical machine shop can only setup & machine a block. They have no way of properly digitizing a block & inspecting the data. In other words, most machine shops machine what's there, & if it's incorrect from GM it stays incorrect. It's not the machine shops fault, necessarily. They just don't have the ability to check the block & put it on proper blueprint specs. Now you're probably thinking how far off can a GM block really be? I can tell you it will really surprise you to see what we have to do to correct some of these LS blocks. Obviously, the engines will run with the block machined incorrectly, but if it's possible to correct these issues why not do so? Most shops aren't willing to spend in the $500,000 range to build a state-of-the-art machine shop specifically for LS engines. We ONLY machine LS-based engines! It's what we love to do, and as a result we felt our best option was to invest the money to make the best possible product available.

We didn't change the pricing on our short-blocks when we invested that money. Our goal was to bring the production in-house so we have better control over the product & can make sure we build the best possible short-block every time.

With a TSP short-block you get the following:

* CNC Digitize blocks every time
* CNC blueprinting
* CNC Stroker Clearancing (same clearance every time rather than some $5 a hour guy hacking too much out of a sleeve)
* CNC cylinder chamfers (rather than having 8 different chamfers changing every cylinders compression)
* Every block is precision-honed with a brand new Sunnen hone using two torque plates & various covers installed & torqued on the block (to replicate the blocks operating environment as closely as we can)
* Precision balanced using the industry-leader CWT balancer with properly trained technicians that treat every rotating assembly like a race engine. You would be surprised how much power you can lose when a rotating assembly is not balanced perfectly!


These are just a few of the advantages. I could go into a LOT more detail if so desired.

To put it simply, we could have built an average short-block & been comparable to other short-blocks available, but good enough just isn't good enough for our customer.

[1up5dn]

So for a guy (like myself) that doesn't want to go FI, how much gains would I expect to see to stroke my LS3? I currently have a Luniati custom ground cam, Kooks lt headers, etc.

I assume that stroking would be my next logical step. I just don't know if the cost versus gain is worth it, but don't know what to expect.


Chris....

[Jason 98 TA]

We actually do just as much 416-418 & 427 LS3 N/A engines as we do boost stuff. The power depends a lot on the components around the short-block. We ship 675 flywheel horsepower 418 short-blocks using the PRC 237 cathedral heads, and will be putting together a 427 LS3 with the all new PRC aftermarket casting LS3 heads very very shortly!

[CC Performance]

Originally Posted by 1up5dn

So for a guy (like myself) that doesn't want to go FI, how much gains would I expect to see to stroke my LS3? I currently have a Luniati custom ground cam, Kooks lt headers, etc.

I assume that stroking would be my next logical step. I just don't know if the cost versus gain is worth it, but don't know what to expect.


Chris....

The power is made in the heads and valve-train. Here is an example of a so called state of the art build we corrected... A $13,500 LS7 427 build...
Complete long block customer only made 525 to the rear wheels in a Corvette. These are pathetic results... The heads and cam choice were that of someone who had never been to school to build an engine and it showed horribly. This was a shop with state of the art equipment, their own line of heads.. etc..... There is a lot more to an engine than just a few components...

So when you ask is it worth it? It all depends on who you get together with to build your combination. We've seen 600+ rwhp vs that 525 rwhp with the same 427 cubic inches by using proper heads and a cam and setting up the valve-train correctly.


I keep saying this and will again... The power is made in the heads cam and valvetrain... You can have 454 cubic inches and still make just 525 to the wheels.. Its the proper combination that gets the job done

[1up5dn]

I was afraid you were going to say that. I think I will be forever gun-shy to pull the trigger. I wish all you guys were closer, then I would feel more confident to move forward!

Thanks for the information guys, I really appreciate learning this stuff.



Chris....

[CC Performance]

Originally Posted by 1up5dn

I was afraid you were going to say that. I think I will be forever gun-shy to pull the trigger. I wish all you guys were closer, then I would feel more confident to move forward!

Thanks for the information guys, I really appreciate learning this stuff.



Chris....

Its really subjective.. We can get you 535 to the rear wheels or 575, it all depends on you budget. Its not guess work at all, it's science and experience.