Exotic American V8! 99% of People Have Never Seen this Engine (Wilkins Racing Engines' RY45)

If you think the only interesting engine builds are super low buck junkyard scrounges, then you may want to hide your eyes from this one, because as far as cam-in-block American V8 engines go, this is about as exotic as it is. After the success of Ford's first purpose-built race engine for NASCAR, the FR9, which came out in 2009, Doug Yates, who is president and CEO of Roushates Engines, saw that many of the qualities that made the FR9 a great engine for NASCAR cup competition could also benefit racers in other disciplines. And he should know, as the only engine builder for Ford-supported NASCAR teams in the Cup Series, Roushates Engines played a huge role in the development of the FR9. So they took the blueprints for the engine, ditched the aspects baked into the design specifically around NASCAR rules, made some changes to help make it more affordable to race teams that aren't racing on NASCAR cup budgets, which, let's be honest, is practically all of us, and came up with the RY45. The RY in the moniker stands for Roush Yates, and the 45 stands for the block's 4.5-inch bore spacing, 120 thousandths larger than the 4.380 bore spacing of the 351 Windsor. So far, the major market for the RY45 has been dirt super late model racing in a carbureted format, but engine builder Sandy Wilkins of Wilkins Racing Engines in Mooresville, North Carolina, has been developing his own versions of the RY45 to do some amazing things in other forms of racing. Besides being a very successful engine builder, Wilkins is also a racer himself. In fact, he won the NHRA Top Sportsman Championship in 2019. But interestingly, he was also at Roush Yates Engines as part of the team that developed the RY45 before going off on his own a few years ago. Although a big part of his business is big block builds for some serious drag racing, he's also done some really cool builds using the RY45, including some top flight drift teams who you've probably heard of, and, as you can see here, for drag racing. This build, however, is going to be very different. This time, we're going off-road truck racing. Carlson Motorsports races in the Premier Pro 4 class in the AMSOIL Championship Off-Road Tour. These are short course off-road races, and they first started running a Wilkins Motorsports RY45 last year with great success. Wilkins said when he first began talks with Carlson Motorsports to build their engines, they told him they needed 890 to 900 horsepower to be competitive in the Pro 4 class. So, he recommended the RY45 and ended up exceeding expectations with a 925 horsepower build. Obviously, they were ecstatic with the results. And here is last year's truck doing a little testing. It sounds so glorious, I'm just going to shut up and let you listen for a minute. If you love the sound of an American V8 screaming at 8,500 RPM, then we can be friends. Anyhow, we're joining Wilkins as he's updating the Carlson race engine for the 2021 race season with ideas for making even more power. This is one of the few RY45 engines currently running in the series, and Wilkins does a lot with the engine that's totally his own creation. So, you'll notice, and hopefully you'll understand, that this video won't have a ton of specific detail to this engine like I normally do. Things like cam specs, even the boring stroke, and some other things. Wilkins has worked hard to develop this engine package that is very competitive, and he doesn't want to give it all away quite yet. But the gist of this video is to share all the many cool things built into the RY45, an engine that very few people have seen before. And we'll share as much as we can about this race engine, which honestly is very, very cool. Anyhow, enough talk, let's get started. Like I mentioned earlier, the RY45 is largely based on the NASCAR Cup Ford FR9 race engine. It's a modern casting with all the tricks. A wider 4.5-inch bore spacing allows for larger pistons and valves for better breathing. And the aluminum block casting is actually scalloped around the water jackets and head bolts to minimize weight. Maximum bore diameter for this block, which is now cast in aluminum, is 4.25 inches. One difference the RY45 has from the FR9 is the ability to handle more cubic inches. Cup engines are limited to 358 cubic inches and a 9-inch deck height. So they're basically built around a super short 3-inch 280,000 stroke. But the RY45 has a 9-200-inch deck height and a revised main webbing, so the stroke can be as long as 4 inches. And that means the engine size can be pumped up all the way to 460 cubic inches. Wilkins already has a camshaft installed in the block. He prefers to keep his cam specs to himself, but I can tell you that it's a solid roller cam cut from billet steel. The cam tunnel is raised an inch and accepts a big 60 millimeter diameter cam. The cool thing here is the block is cast so the cam tunnel is completely sealed. There are no openings to the cam except for the lifter bores and a single port in the lifter valley for the dry sump oil pump to suck out the excess oil. That means that all the oil bleeding off the lifters fills the cam tunnel and the cam and the rollers in the lifters operate in a complete oil bath. Up front, the cam seal and thrust bearing are both housed in the cam retainer. Once it's bolted up, the camshaft is totally sealed off from the outside world. In this shot, you can also see the thickness of the block deck by the ridge in the outside of the block and how the casting actually bulges out for the head bolt holes. They're just signs that the engineers worked to eliminate any extra material possible to reduce unnecessary weight. The crankshaft is a polished billet steel unit from Bryant. Wilkins is keeping the bore and stroke a secret because he says he's using a combo that's not typical, at least in this series. I do know that the engine displacement will be 438 cubic inches, but that's because the rule book says that the engine displacement can't be greater than one cubic inch per 100 pounds of truck weight. In race trim, the Carlson Pro4 truck weighs 4,400 pounds and they don't want to add weight just to have a bigger engine. So that leaves two extra cubic inches as a margin for error in case the team makes changes to the truck during the season that somehow lightens it up. The main bearings are coated units from Clevite and the mains are sized at two inch 750 thousandths. If you're a fan of the old Cleveland designs, that's going to be a bit familiar to you. Wilkins also checks the clearances on the rod bearings which are coated Clevites as well. And these pads at the base of each cylinder bore are for piston squirters. Another cool feature of the RY45 is it has internal oil galleries for both the piston and the valve spring oilers. Ford used a one-piece seal design for both the front and the rear main seals. They slide onto the crankshaft before installation into the block. Then Wilkins applies a light coat of sealer. Since we're going to be pulling vacuum inside the crankcase, this is as much to keep outside air from getting into the engine as it is to keep oil from leaking out. Then the Bryant crank is ready to be lowered into place. The main caps are billet steel and all five use four fasteners each. We're actually using studs here but Wilkins slides them into place after the caps are tapped down and the centers are locked down at 70 foot pounds. As soon as that's done, he uses these giant c-clips that fit into a groove in the outer caps to lock the seals into position. Wilkins says there really isn't an issue with the seals working themselves loose, but since they don't have to be driven in like on a standard small block, the engineers just added a little bit of extra insurance. The crankshaft is cut to Wilkins specifications and has an extra large fillet at the edges of the rod journals. The fillet, which is the curve that transitions the crank journals to the throws, helps strengthen the crank. But to make room for the larger fillet, the rod bearings have to be manually chamfered so they won't rub. Wilkins actually has a fixture set up so he can do this quickly and cut the chamfers on a lathe. Here you can see the modified bearings at home in the rod caps. The rods we're using are a set of Carrillo forged H-beams. How long are they? I don't know because Wilkins wouldn't tell me, but that's okay. The rods are fitted to a set of MAHLE box-on-box design lightweight pistons. These pistons cut every gram of weight possible by minimizing the skirt area and also by moving the piston pin bosses inboard to shorten the pin length. And then the outside edge of the ringland area are reinforced by struts from the pin bosses. The pistons are flat tops with just enough material removed in the valve pockets to keep knocking the valves into the pistons. With the rods and pistons assembled, Wilkins sits down to install the rings. He says proper ring gap is critical and will often spend two hours gapping and thoroughly cleaning the rings, which can sometimes even include lapping them. As you can probably tell by the look of his assembly room, Wilkins is a stickler for cleanliness. But that's especially true when it comes to the piston rings. He says contaminants left on the rings is one of the leading causes of damaging microwelding between the ring and the land. The rings are sized at 43 thousandths for the top and second ring. That's not the thinnest out there these days, but the engine must live through at least 12 hours of full bore race time, which equates to a full season in a very dirty environment. So now we're ready to drop these rods and pistons into the block. Rich Gottfried sets about giving the cylinder boards a final cleaning while Wilkins lubes the rod bearings. By the way, can you believe this block has already seen a full season of dirt racing? It can be pretty difficult to get dirt out of porous aluminum, but there are no signs of dirt anywhere on this block. It's just another sign of the meticulous nature of the guys at Wilkins Racing Engines. Wilkins attaches the rod caps, but before tightening the 7-16th cap bolts, he measures every one with no torque on them. The rod stretch gauge has already been zeroed out against a machined metal block of a known length, which is just a little over an inch. Then he measures every single rod bolt and marks the length on the block at the oil pan rail. Next, he tightens each to an incredible 100 foot pounds and measures every bolt to check the new total length after it's been stretched. That too gets marked on the block. Total rod bolt length after tightening minus the loose bolt length is the amount of stretch, and the target is six to six and a half thousandths. Then, of course, everything gets transferred over to the build sheet. This method ensures he knows every single rod bolt is correctly stretched, which is a big deal when your redline is going to be 8,500 rpm. And here is a look at the top of the Molle pistons sitting pretty in their bores. Notice that these are flat tops, even though we'll be running a pretty extreme compression ratio of just under 15 to 1, because a dome can reduce the speed of flame front during ignition and hurt power. Earlier, I pointed out the machine paths on the inside of the block to provide pressurized oil to the piston squirters. Here are the billet squirters that bolt up to them. You can see the jets on the ends to meter out the amount of oil coming out. They just bolt right up to the block and o-rings provide a leak-free seal. But you do have to be careful with the stroke and type of connecting rods you use. As you can see from our build, the squirters can get pretty close to the rods. And that's the rotating assembly. The oil pan is a piece of automotive jewelry cut from a few pieces of aluminum billet. The inside of the pan is machined so that dams fit up against each of the main caps and create four discrete segments inside the block. That's so the external oil pump can scavenge both oil and air. Notice also that the pan has a reusable oil ring to seal against the block instead of the usual gasket. Instead of having a bunch of external lines, the bottom section of the pan is hollow and includes ports. The oil pump bolts directly to this flange and pulls from the ports for very efficient scavenging. And once again, we're using o-rings and no gaskets or silicone to seal things up. And here you will see the only time silicone is used in the entire build. Wilkins applies a bead to the flange on the front and rear main caps until they bump up against the o-ring. And just like that, the pan is ready to be lowered into position and bolted tight. Notice the bolt holes on the crank flange. The crank snout also lacks a keyway and isn't even threaded for a crank bolt. Usually, the next step on an engine build is to bolt up the timing set, but the RY45 switches things up a bit here. To help move the engine's center of mass closer to the rear of the engine, the harmonic damper goes on before the timing set, and it's located with this dowel on the inside of the hub. It slides on with zero press against the crank snout, and then the lower timing pulley also goes into place. The dowel pins are just there to locate the crank and pulley, and then several ARP bolts are used to secure everything so they won't move. Then the upper pulley and the cog timing belt can go on. The can retainer is keyed so that the upper pulley can only go on one way. And now comes a test I can honestly say I've never seen in any engine shop before. The tension on the timing belt is critical so that the cam timing is as stable as possible without causing the belt to be so tight that it creates excess drag. Wilkins tests the timing belt tightness with this little gadget called a Hertz meter. It actually measures the sound frequency created when he flicks the belt, and it lets him know if it's properly tight. The target is 135 Hertz, and if it's off, he has very slightly shorter and longer belts in stock to swap out until it's perfect. Once the timing belt is on, Wilkins can degree in the cam. I always geek out over the gear the former NASCAR cup engine builders usually seem to have on hand, and Wilkins is no different. But before you send me an email asking where you can buy this trick timing pointer, I'm pretty sure it's all custom. The lifters are keyed rollers from Jezzled. Keyed rollers don't have a link bar like you might be used to seeing. Instead, they have a key or a little bump on the body of the lifter, and it fits into a machine slot in the bronze lifter bore bushing. This method of holding the lifter steady eliminates the link bar, which means that the lifter can be shorter, which cuts valve train mass. They're also helpful in applications like this because there's no link bar to get in the way of extra large push rods. These particular lifters are pretty big at 937 thousandths of an inch in diameter. Stock Windsor size for comparison is 874 thousandths. Plus, they have a diamond hard DLC coating on the body to minimize wear against the lifter bore, even with super aggressive cam lobes. A lot of science obviously went into cylinder sealing. There are a ton of head studs, they also come in three different sizes. One thing that's cool is that the hex on top, which allows you to use an allen key to thread the studs all the way in, is the same size no matter the size of the stud, so you don't have to keep swapping out tools. The head gasket is a multi-layer steel piece from Cometic, except this isn't standard for the RY45. Wilkins has the engine run its coolant under pressure, which helps eliminate hot spots, and he's also modified the head gasket to have the coolant flow meet his specs. The gasket even carries his name, and obviously, you can only get these from Wilkins Racing Engines. And now that we've got the head studs and gaskets in place, we're ready to take a closer look at the cylinder heads, which, seriously, are works of art. These RY45 heads have a combustion chamber that's just 37 cc's, which, as we've already mentioned, will bring the compression ratio to just under 15 to 1. The intake valves are 2 inches 170 thousandths in diameter, while the exhausts are an inch 650 thousandths. Both are titanium, and both use a valve stem that's just 7 millimeters in diameter to minimize valve train weight. I love how the engineer sculpted it so that the head is exactly the size it needs to be, and not one square inch larger. Here, you can see the intake face of the heads. The small ports underneath the intake ports are for coolant to exit the heads. Both the intake and exhaust ports have a large cross-sectional area design that's the same as the cup teams use on the FR9. Dirt late model teams typically like a smaller port package to increase torque down low, but Pro4 trucks use a 6-speed sequential transmission that allows the driver to keep the RPMs right in the sweet spot all the way around the track, so Wilkes prefers to tune towards a higher RPM power. When I asked about the port volume, I was told simply that they're big enough to go fast. So there you go. Up top, the valve spring package is also a secret. You can tell that it's a double-nested spring setup, and both locks and retainers are titanium. And from this angle, you can sort of tell that the valves are cannoned to point them away from the cylinder walls and improve airflow into the chambers. The heads also have built-in internal oil galleries that feed these spring sprayer towers. You can also see the jets in the towers to tune the amount sprayed onto the valve springs. The Chevrolet equivalent engine for NASCAR, and they call theirs the R07, puts the sprayers in the valve covers. It's always interesting to see the different ways the two manufacturers chose to make power. And if you're interested in seeing a video on that engine, I did a fun build with the R07 recently, and we'll include a link to that video in the description below. Wilkes torques down the cylinder head bolts. With three different stud sizes, torquing down the heads isn't the simplest task. Although if you use an RY45 specific stud set, the nuts for the two largest stud sizes take the same socket, which is pretty cool. Interestingly, the spec sheet provided by Roush Yates spelling out all the torque specs and lubrication requirements for assembly is nine pages long. So there's that. To protect the titanium valve stems and provide more surface area for the rocker tips to roll across, Wilkes installs lash caps on all the valve stems. The rocker arm setup is from Jessel, and it has a really aggressive 2.15 to 1 rocker ratio. The steel rocker base bolts to a thick pad machined on top of the cylinder heads with eight fasteners to hold it down. You can get the rockers with adjusters or without if you want to cut a few additional ounces for the valve train weight. But for this build, Wilkes went with the rockers with built-in adjusters because the race team will be handling some of their own maintenance. Here, you can see the lightweight water manifold that goes in place just below the intake. It routes water from the cylinder heads back to the radiator. This allows the intake to be removed without cracking open the coolant system, and it also keeps hot coolant away from the incoming air and fuel. The valves are given a cold lash of two thousandths for the intakes and six for the exhaust. They will get reset once the engine is nice and hot on the dyno, but that cold lash setting should at least get as close to Wilkes' hot lash target of 16 and 18 thousandths. And then Wilkes broke out yet another cool tool I've never seen used before. This ridiculously awesome fixture centers a dial indicator over each of the rocker arms so he can measure actual valve movement after the engine has been assembled. The main thing Wilkes checks with this tool is how close the valve springs get the coil bind at maximum valve lift. He takes each valve to full lift and then uses this tool to continue compressing the valve spring until it reaches coil bind. Running a valve spring close to coil bind without actually binding up the spring can help limit damaging harmonics. Ideally, he says he wants each spring to be within 50 thousandths of an inch of coil bind at maximum lift. For this specific build, Wilkes found he still had too much travel. So to bring the springs closer to coil bind at full lift, he removed each valve spring and changed to a slightly thicker shim underneath the spring. Then he repeated the process and confirmed that everything was dead nuts correct. The motor plate is one of the most complex I've ever seen. It's anodized aluminum and CNC cut with ribs for extra strength. All the accessory drive components mount directly to it, so there's not a lot of brackets and stuff to fool with. Oh, and of course, it also has an integrated timing pointer. The RY45 was originally designed to use a carburetor and a conventional distributor. Wilkes is setting this one up with port fuel injection, so he needs a crank trigger and cam position sensor. So for the cam sensor, he modified the front cover. He's also got a modified crank trigger that mounts up like this. The original distributor hole in the block will be capped off. This oil line will run from the port to the cam tunnel and connect to the oil pump so it can scavenge oil right from the top of the cam tunnel. Another unique feature is the water pump doesn't just push coolant straight into the block. Instead, it uses a pair of hard lines like you see here, and they put coolant in at the very bottom of the water jackets in the block to reduce the chance of developing hot spots. The hard lines connect up with quickly removable Wiggins clamps. The intake manifold is a billet single-plane unit from Mike's Racing Heads that's been modified for fuel injection. And obviously, it's got some pretty big runners to match the intake ports in the cylinder head. But before we drop it in place, check this out. Notice the big dowel pins on either side of the intake gasket. One of the goals of the RY45 was to eliminate the use of silicone wherever possible. So holes in the intake gaskets slot over the dowel pins to position the gaskets perfectly until the intake manifold can be bolted down, and then the dowel pins are removed. Since we've seen it last, Rich has finished setting up the intake manifold with the fuel rails and crossovers, all the wiring connectors for the fuel injectors, and the spacer. The spacer is a four-hole tapered unit that helps direct more air through the throttle body, and every additional bit will help here. That's because so far, everything in the engine has been wide open, but the throttle body is a spec unit required by the rulebook, and it's the big choke point in the whole system. It's a unit made by Braswell, and although it's a nice piece, it's only capable of flowing a thousand CFM. That may sound like a lot, but with these high revving motors, it's definitely going to be a restriction on power. The multi-stage external oil pump bolts directly to this flange on the billet oil pan. Once again, we're all about eliminating external lines that create complexity and potential leaks. Plus, the oil pump is also more protected as it's tucked in nice and tight to the side of the engine. And with that, we're ready to move our RY45 build to the dyno room. This is Shawn Ray, the engine tuner for Carlson Motorsports, who will follow the engine to the track. At first glance, when everything is hooked up, the engine may look like a mess of wires, and there is definitely a lot going on with the engine management system. But there are also some very cool organizational tricks to make engine packaging simpler. Namely, this bracket that bolts across the front of the engine that brings oil, coolant, and fuel to one easy-to-reach spot so you can hook up the pressure sensors. This is especially important because weight distribution in this class is critical. That's why the engine in a Pro-4 truck is moved from underneath the hood, where you'd expect it to be, to right beside the driver. It can be a little difficult to tell in this photo, but that's the driver's seat just to the left of the engine. This helps keep the trucks balanced as they're flying through the air, but it can also make getting complex engines into and out of the chassis a pain. So anything you can do to simplify the process is a must. All of the engine controls are handled by an ECU from Motec. This is actually the spec system required by the rules, but Ray says the Motec ECU does allow a tremendous amount of control over the engine. It however isn't as user-friendly as some other popular systems like Holley's Terminator ECU, so a specialized tuner with significant training like Ray is usually needed. The fuel injectors and the coils are also spec units according to the rules. The Motec will be firing a set of 1,000cc fuel injectors, and the coils are basic units from the Gen 4 LS. So after Wilkins spins up the external oil pump to prime the system, and Ray makes a few last-second checks to the crank trigger pickup and other things, we're finally ready to fire this engine up. So let's see what Wilkins has been able to come up with. The engine dyno doesn't have crossover pipes, so while this engine revving to 8,500 rpm sounds incredible, it doesn't have that same ridiculous tone that you hear in the practice video. As you can see, Wilkins ran the pull from 6,500 to 8,500 rpm. That's because the Pro 4 trucks, like we already mentioned, will run a six-speed sequential transmission, so they can keep the engine up in the power band all the way around the track. So what did we get? How about 657.8 foot-pounds of torque at 6,600 rpm and an amazing 958.4 horsepower at 8,500. Wilkins was definitely happy because that's 25 more than he was able to give Carlson Racing last year, and they were already excited about what they had before. With the spec throttle body, Wilkins says this is about all the peak power this engine combo will be able to make, but he and Ray spent a lot of time tuning the engine to make as much power as possible under the curve. Usually, engines that make power so high in the rpm range are very temperamental and peaky, but this RY45 had averages of 637.5 foot-pounds of torque and 908 horsepower between 65 and 8,500. That should be plenty to keep a Pro 4 truck up front at any race they want to go to. Now, if you've enjoyed this video, please like and subscribe and tell us in the comments what you think of this exotic American V8. Thanks for watching, and we'll see you next time with another great engine build.