Boost-Ready Stroker LS3

(Pat)>> You're watching Powernation!

(Pat)>> It's a busy day for Engine Power. We get started on an LS-3 stroker designed for big power on pump gas.

(Frankie)>> Plus, we get our hands on a state of the art crankshaft balancer. [ Music ]

(Pat)>> Today we have a very cool and exciting build on this engine, and like all projects this started out with some sort of budget. Well, something changed and then that affected this, and one thing led to another, and now the budget is blown, but for how much power this is gonna make and how good it's gonna run on 93 octane pump gas and who's actually gonna be hammering on it we have to put some very high quality parts in this bullet to make it last for the long run. It all starts with the parts we have laid out on the table, beginning with a Summit Pro LS 43-40 forged four inch stroke crankshaft, and we are holding everything together as usual with ARP fasteners. We also have a full compliment of Comp Cams valvetrain including one of their hydraulic roller cam shafts, their new Evolution lifters, and a bronze thrust plate with a billet timing set. For our pistons we went with DSS. They made us a custom set of pistons with a dish to our specifications, and they will be sealed up by a quality set of Total Seal AP Profile piston rings. Hooking those pistons to the crankshaft are a set of Eagle H-beam 43-40 forged rods with seven-sixteenths L-19 bolts with a 6.125 center to center length.

(Frankie)>> We've done our fair share of LS', and normally they are of the iron block persuasion because they're relatively cheap, easy to get, and they hold a great bit of power. But this time to save a little bit of weight and to do something a little bit different we are going true LS with an all aluminum LS-3. Now this one has a little bit of work to be done, but so far it's been bored and honed to a final bore size of 4.085. And with our four inch stroke crank that's gonna equal 419 cubic inches. Now with any stroker build the most important part is mockup. So that is what we're gonna tackle first. Make sure that we don't have anything that hits anything else.

(Pat)>> It's going to.

(Frankie)>> Probably. We'll temporarily install the King Racing main bearings in the rear, middle, and front saddles. The front and rear will support the crankshaft, and the thrust bearing will keep it located during mockup. These are used stock main fasteners torqued to 55-pound feet for now. [ Music ]

(Pat)>> I like! [ Music ]

(Frankie)>> It's just for mockup. Just enough to make the housing round good enough.

(Pat)>> But it has to have torque on it because otherwise the bearings won't have crush, therefore the bearings won't be running.

(Frankie)>> One of the rod and piston assemblies is dropped in without rings, and we rotate the engine to check for interference. [ Music ] If we're lucky. We're not lucky!

(Pat)>> Not gonna be lucky on this. We'll use a marker to trace where the rod hits the block on the number one and two cylinders. If you need to clearance the block at home you can use a carbide burr, but we're gonna put our block in the Vectrax mill to make quick work of it. To ensure the cuts are consistent and accurate the block must be precisely located in the mill. To do this we'll use our s-p-i dial indicator chucked into the quill. To get plenty of clearance we chose a three-quarter inch diameter four flute end mill. To make sure we don't overshoot things several light passes are made to get the correct clearance depth. [ compressed air hissing ]

(Pat)>> Once the first clearance notch is complete, we moved down to each cylinder following the engine's bore spacing.

(Frankie)>> To prep the block for deburring and cleaning we'll drive out the cam bearings. Next, we'll take a small hand file across any sharp edges. Just enough to round them off. This helps prevent stress risers and tearing of the skin or rags during assembly. On the less crucial areas of the block we'll use an 80-grit cartridge roll. Since this block is aluminum I'm using a light touch and letting the abrasive remove a small amount of material. [ Music ] Then the threaded oil gallery plugs come out. [ Music ] Finally, the block goes into the jet washer for initial cleaning. [ Music ]

(Pat)>> Up next, Randy Neal shows us how to balance our crankshaft to perfection.

(Frankie)>> Then it's back to work on the LS-3.

(Pat)>> How's that look?

(Frankie)>> It's pretty cool!

(Pat)>> Get out of there. A couple of weeks ago we received a piece of equipment that brings us one giant step closer to being a fully stocked machine shop. Just as important, it gives us the tools we need to show you the science behind one of the most critical parts of high performance high r-p-m engine building, crankshaft balancing. This is CWT Industries Multi-Bal 5,500. A 4,000-pound beast designed for precise, accurate crankshaft balancing and adjustment. Once we got the balancer into place and leveled, we outfitted it with everything we would need. To help us get going fast we had no less than the founder of CWT Industries, Randy Neal. Tell us a little bit about balancing. Balancing is one of those things that people think there's a lot of voodoo to it, and I don't know if I've ever heard anybody say it better, it's science.

(Randy)>> A lot of misnomers. Some people define it as voodoo. Well, the fact of the matter, all balancing is cored within the law of physics. Let's call it science. The problem that we have at Industries is that lack of knowledge generates false procedures, a-k-a voodoo. We really have done a deep dive to make sure that anybody with a reasonable amount of talent, you can run this machine.

(Pat)>> You're the designer of this machine. What makes this machine built different? When we moved it in here it was super heavy, and those things are 4,000 pounds.

(Randy)>> We've learned that rigid is a factor, but dampening is more of a factor. So, as we measure rotationally we generate energy. It's important that we find the energy here, not contributed or polluted by other inputs. We're very unique. Our algorithms, which are proprietary, they basically understand thermal growth. They also understand the vertical loads. They know all this stuff, and again it's doing it back here. You don't need to know this stuff. It does it. Let me just show you something. Let's see if we can do something real quick here. This is on the left stanchion over here. Now I'm gonna have you just touch that, Pat. That's you. Now in doing so every time we rotate it gives us what's called a sinusoidal wave. So as this rotates it's sensing that, but what's unique about that is the level of sensitivity. Now I want you to go ahead and touch the bottom. Go ahead, go ahead, nada. So, we have totally isolated all of the energy right here. This is all about measuring accurately and simply, and you'll find as we interface with this we build the bob weight card and this thing will hold over 20 million samples. You fill that up, I'll give you another computer no charge.

(Frankie)>> The first step and one of the most critical is to gather everything that will make up the rotating and reciprocating assembly. The Multi-Bal 5,500 has a really helpful feature. Once you've weighed a component you simply hit the print button on the scale and the computer builds the bob weight card for you as you go. After numbering the pistons, we weighed them along with the wrist pins, locks, ring pack, and bearings. By entering a description and part number for each component into the computer we'll have a permanent database of everything in our engine's rotating assembly.

(Pat)>> While Frankie finished up the bob weights, I attached the drive belt to the crankshaft and indexed it to the machine.

(Frankie)>> After spending several hours showing us the ropes, Randy had to hit the road but he gave us the tools and knowledge to get the job done. We spun up our crank for the first time and not only was imbalanced way above our tolerance, the location of the imbalance was not ideal.

(Pat)>> Because of those results this makes this crank a little bit more challenging to balance because where it wants weight removed is a place where we actually can't remove it. It's not on a counterweight. So, we have to chance where that imbalance is located.

(Frankie)>> The way we're gonna do that is actually add material. So, we've made some steel slugs. Both will be pressed in. One in the reluctor wheel here, and the other in the front counterweight. We'll get them pressed in place and then fully weld them for extra insurance. To make them a little bit easier to install we've had them sitting in the freezer for a while.

(Pat)>> Right next to my ice cream!

(Frankie)>> Grab two. [ Music ] These steel slugs have a one and a half thousandths press. To support the reluctor wheel and provide a stop for the slug we slid in a feeler gauge. [ hammer tapping - sped up ]

(Pat)>> Glorious!

(Frankie)>> For the front insert it is crucial that it be welded in place since centrifugal force will constantly be trying to turn the insert into a high speed projectile. [ Music ] For extra insurance the back slug is welded in as well.

(Frankie)>> Ready?

(Pat)>> Yeah, spin it. After spinning it again we're much happier with the results. So now we are on opposite sides. So, we go to the back here, roll this back and wait, and at 2.796 grams.

(Frankie)>> That's within six degrees of 180, which is just what we wanted, and the back is really close. The front, we overshot it a little bit but that was on purpose because it was in a place where we couldn't get to. So now we've overshot a little bit, and now we can just work it down from there.

(Pat)>> We started grinding on the heavier end, which was 27 grams over. We worked on the counterweight to remove about half of the excess mass. After several times grinding and re-spinning we are able to get the crank dialed in just right. Yeah baby, look at that!

(Frankie)>> That's perfect!

(Pat)>> That was totally not by accident but kinda by accident because it's so close. Point one ounce inch and point one-zero eight. Eight thousandths of an ounce of an inch away, and our balance tolerance quarter ounce inch.

(Frankie)>> They're almost directly 180 degrees apart from each other. In terms of forces on the center of the crank that really minimizes it down to point one-four-seven grams. So that's really nice. This is either side here, but this is what we started with. And even at seven thousand that's probably the most this crank will ever see. 122 pounds of force on the left side and 124 on the right before we started. Now we've minimized that down to eight pounds and nine points. That progressively gets larger with r-p-m. The more we can minimize that the better it's gonna be for the engine in terms of bearing wear, and life, and things like that.

(Pat)>> It makes everything look better. That's pretty happy, and the best part is no holes. We actually profiled after we were done. We knew what our weight was gonna do for the most part, and then the less holes you can have in the crank the better it is for windage and a couple of other things.

(Frankie)>> Not only does it look nice, it actually performs a little bit nicer too.

(Pat)>> That is pretty spiffy for our first crank on our machine.

(Frankie)>> Print these right out and then we can get this sucker off of here.

(Pat)>> This is just the tip of the iceberg. We'll explain a lot more balancing tech in the future. Up next, to build a high performance engine it takes planning and the right parts.

(Pat)>> Before we continue on with our project, I'd like to clear up something you may be confused about in crankshaft balancing, and that is the difference between external and internal balancing. External balancing considers it needs everything hooked to the crankshaft to get the shaft to balance. The counterweight itself is not large enough to counteract the bob weight's total. So, we need extra weight on the crankshaft. So, it moves that weight for removal back onto the counterweight, and that can be accomplished by using a combination of the flywheel and balancer, or maybe one or the other depending on the application. Now internal is totally different. It doesn't depend on anything like the balancer or flywheel for balancing. Everything is contained on the shaft. The crankshaft counterweights have enough mass and material to counteract the bob weights' total without the need to add external weight via the flywheel or balancer. There is a lot more information concerning balancing, and if you have any questions about what would be right for your application you can always consult the experts at Summit Racing Equipment. Now that it's been balanced it's always a good idea to run a polishing belt over the journals of the crankshaft. We're using the Goodson crank polishing tool and a cork polishing belt to get a better than factory finish. This is a task that is usually handled by the machine shop after the shaft has been balanced. Looking good!

(Frankie)>> Next is a crucial part of any high performance engine build. It's something we don't always show you but we always do it. We're talking about wrist pin vertical oil clearance. This is very similar to measuring main bearing and rod bearing clearance. After measuring the wrist pin, we'll use the micrometer to zero out a small dial bore gauge. This instrument measures to ten thousandths of an inch, and we're looking for between eight-tenths and one thousandths of clearance for this application.

(Pat)>> Before the rods and pistons go through the final cleaning process, we'll engrave the cylinder number in each one so they are permanently marked. The rods and freshly polished crank go into the jet washer for 30 minutes at 150 degrees. Once the pieces are clean we'll let them cool off to ambient temperature. This is important because all of the components and measuring tools have to be the same temperature for accurate measurements. For this application we're using a set of King Racing XP bearings from Summit Racing Equipment. Because the bearings are narrowed, they must be installed in the correct location so the bearing's offset clears the radius on the crankshaft.

(Frankie)>> Connecting rod bolts are the most critical fastener in an engine because of the environment and stress that the have to endure. This makes picking the material they're made out of very critical. ARP is the leader in quality connecting rod bolts, and they have a couple of different choices when it comes to the material for your build. You've commonly seen us use 87-40 and ARP 2,000 materials. 87-40 has a tensile strength of around 180,000 p-s-i, which makes it a great upgrade over an o-e-m fastener for stock or mild applications. ARP 2,000 is much stronger with a tensile strength of around 220,000 p-s-i, and this makes it a great choice for rod bolts, main fasteners, and head fasteners in high performance high r-p-m builds that are well maintained. For our application, because we're looking for extreme durability and longevity, we picked L-19 fasteners. Now these are much stronger. They have a tensile strength of around 260,000 p-s-i, but they do take some extra care. Because the material is really susceptible to stress corrosion and hydrogen brittlement, it's really important that when the material is clean and dry you don't actually touch it with your bar hands because the acids can help induce that corrosion. It's also important that they're not cleaned with any chlorinated cleaners like Brakleen. We've gone ahead and cleaned ours with lacquer thinner, and you can if you're careful get away with touching the bolts if they're covered in oil and your hands are covered in oil because it gives a protective layer between your skin and the material, but a lot easier and much better way is just to use some gloves. [ Music ] ARP Ultra Torque Assembly Lube goes on the threads and under the head of the fastener. To prep the rod for checking oil clearance the bolts are torque per the manufacturers' guidelines to achieve the appropriate rod bolt stretch. Checking the vertical oil clearance is the same as the process for the wrist pins. Once the mic is set to the journal the dial bore gauge is zeroed out and we can get a direct oil clearance measurement. They all come in between 24 and 26 ten thousandths. Exactly what we wanted.

(Pat)>> Once the rods, wrist pins, and pistons are thoroughly lubed the wrist pin slides into place and the rod is worked back and forth making sure the assembly lube is properly distributed. The wrist pins are retained with dual spiral locks, which gives a little extra insurance and are relatively easy to install with some care and patience.

(Frankie)>> Up next, we finish up the short the block with a forged rotating assembly.

(Frankie)>> We needed a set of piston rings for our DSS pistons. So, we reached out to the guys at Total Seal, told them the specifications on our piston and the application that the engine will be used in. They specifically recommended a set of their conventional AP steel rings in a 1.2, 1.2, 3-millimeter ring pack. The top ring is made of 440-B stainless steel, which is gonna be stronger and have a much longer lifespan. It has a C-33 face coating, which is gonna prevent dirt and debris from penetrating the coating, which could affect ring seal. It also goes through their advanced profiling, or a-p, ring process, which allows Total Seal to hold a much tighter tolerance, which means the ring is gonna be dimensionally much more accurate. The second ring is a Napier design, which is gonna help oil control on the cylinder walls, and our oil control ring pack is a standard tension at 11 pounds, which is gonna work great on the street. The set comes with great instructions on how to properly file your ring and tips on proper installation. For our application we're gonna set the top ring gap at 22 thousandths and the second at 24. One of the most crucial steps of ring filing is to properly deburr the ring after filing so it does not damage the cylinder wall or piston. There's several ways to do it but we use a fine grit India stone. We'll slowly make a few passes to get our desired gap. It's always easy to remove material but hard to put it back. After the rings are fully cleaned they are installed on the pistons. [ Music ]

(Pat)>> We equipped this block with a set of ARP main studs, which get threaded in only hand tight. This required the block to be align honed, which was performed by our favorite local machine shop, Shacklett Automotive Machine. Align honing ensures that the main housing bore is round and straight so the main bearing oil clearances are correct. We've already checked clearances and they look great. [ Music ] After truing up the thrust faces of the bearings we'll install the caps and torque them following ARP's specifications. 60-pound feet on the inner studs, 50-pound feet on the outer studs, and 20-pound feet on the cross bolts. We're using a Comp Cams camshaft with durations at 50 thousandths lift of 239 degrees on the intake and 255 degrees on the exhaust. Lift at the valve is 624 thousandths. Lobe separation angle is 114 degrees. A Comp four tooth billet double roller timing set goes on along with the factory chain tensioner. [ drill humming ] [ Music ]

(Frankie)>> With the number one piston installed, we degreed the cam and set the intake centerline at 109.75 degrees for good street manners. With total seal assembly lube coating the cylinder walls and ring packs the rest of the rod and piston assemblies slide in. [ Music ]

After torquing the rod bolts to the proper stretch our 419 cubic inch LS-3 has achieved short block status. There's plenty more to go on this engine but if you want to see any more of our builds you can go check out our website. [ Music ]