The age-old debate about the superiority of the Chevrolet big-block when compared to the small-block, and vice versa, has been raging since the distinction between the “Mouse” and “Rat” motor was first coined. After all, the old adage goes that there’s no replacement for displacement, right? If you subscribe to that theory, then it makes sense that a big-block would be your weapon of choice. But what if you could have it all? Big cubes in a little package. Enter the LS and Golen Engine Service.
While the LS isn’t the first to cram large quantities of displacement into a small package, it has become somewhat commonplace to find an LS, which is in every way a small-block, to be packing more than 400 cubic inches. LS fanatics the world over, and specifically the guys at Golen Engine, have taken the adage we mentioned earlier to heart and created some behemoth-sized small-blocks. In fact, 500+ cubic inch LS engines have become fairly common, with some mills — typically built using specialized blocks — seeing displacements as high as 510 cubic inches.
In the age of forced induction, however, high-horsepower, big-cube, naturally-aspirated builds seem to have lost their luster. That is, until you produce enough power to destroy anything with an external huffer or even nitrous without the aid of atmospheric modifiers — that’s where Golen Engines comes in. They’ve been building some of the biggest, baddest mills on the planet ranging from big-block to small-block and of course LS for years, and they still believe in a big-cube brute. That’s not to say they don’t have plenty of experience with power adders, but they still believe in the draw of a naturally aspirated mill.
Bigger Isn’t Always Better….But It Usually Is
Chad Golen, the owner and proprietor of Golen Engines, is no stranger to big-cube builds. He’s built just about everything you could think of and has developed a winning formula for extracting good power from just about any combination. When a customer approached Golen about building a 502 cubic inch LS for a C10 project, the first question Chad had for him was about his power goals. The customer wanted to make big power, at least 750 at the crank without any assistance, but wanted to keep everything nice and drivable — though some laughing gas may be used down the line. With his marching orders in front of him, Golen knew exactly where to start.
He kicked things off with an RHS tall deck block. Golen knew he would need enough room to stroke and poke the powerplant to the appropriate size and the RHS block is a great starting point for a build of this magnitude. The newly acquired block was machined and prepared to receive its massive 4.600-inch throw crank.
“The RHS block is all set up for a 502, so their crankcase doesn’t need clearancing, the crank literally just drops right in,” Golen said. “So we did a little line honing and blueprinted the oiling clearances. The block comes in, technically, unmachined, so we’ll hone the mainline and cross-check the bearing and crank to make sure we’ve got our clearances where we need them to be. Then, from there, we are bolting torque plates to it and giving it a light hone to give it its finished 4.165-inch bore. We also decked the block to make sure we were at zero deck after the rotating assembly is in. But, that’s the good thing with that block, there wasn’t a whole lot of specialty machine work. It’s more just the finish work since, as I mentioned, it comes in without the final machine work done which is how we want it.”
To keep a rotating assembly of this scale together, a Callies Ultra Billet crankshaft was selected and is connected to custom forged Wiseco slugs via a set of Callies Ultra H-beam connecting rods. The Ultra Billet crankshaft from Callies is constructed of 4330 alloy steel and features a myriad of journal sizing options as well as aerodynamic counterweights and coating to keep windage at a minimum.
The custom slugs from Wiseco, measuring in at 4.165-inches, are constructed from forged 2618 aluminum and feature a hard anodized coating, tool steel wrist pins, and stainless steel ring pack in a 1.5, 1.5, 3.0mm configuration for the compression ring, wiper ring, and oil ring respectively. All said and done, the 502 cubic-inch mill’s compression ratio sits right at a pump-gas friendly 11.5:1. Golen tells us that at 11.5:1, the 502 is right at the edge of what they typically view as safe for pump gas but will also work well with race fuel and leaves very little on the table.
“Even though it was a pretty straightforward build, it’s still going to be a pretty hard-hitting engine, so you’ve got to make sure everything on it is right,” Golen said. “To make this level of power, you can’t take any of it for granted. You’ve got to make sure you have the valve-to-piston clearances right, the rings have to be gapped just right. You just can’t leave anything to chance when it’s making the kind of power we are with it, so it’s definitely built right.”
Even though it was a pretty straightforward build, it’s still going to be a pretty hard-hitting engine, so you’ve got to make sure everything on it is right. — Chad Golen
With the rotating assembly squared away, Golen shifted his attention to the cylinder heads that would top off the mill. With the desired power numbers in the back of his mind, the choice of cylinder heads would be of pivotal importance to just how much power the 502 could make. Without compressed atmosphere or chemical boosters, Golen knew the mill would have to be able to gulp down massive amounts of air with as little trouble possible. This meant that a high-flowing cylinder head could possibly make or break the build.
With his airflow requirements in mind, Golen turned to the guys at Mast Motorsports for a set of their rectangular port LS7 315cc large-bore canted valve cylinder heads. With a massive 320cc intake runner, canted valves, and 6-bolt design, the heads were just what the doctor ordered. The massive 2.250-inch intake and 1.600-inch exhaust valve sit at a 10-degree angle and 7-degree angle respectively. This allows the set of heads to exceed 400 cfm of airflow at over .900-inch of lift.
Naturally, to keep the valve geometry under control, the heads utilize a Jesel shaft-mounted rocker assembly to tickle the valves. And speaking of tickling the valves, a massive COMP Cams custom ground bumpstick issues the marching orders to the valves and transmits them via Morel Ultra Pro solid roller lifters. Golen tells us that “the cam is large but still decently streetable.” While a solid-roller lifter setup may or may not be the most streetable, depending on what your definition of the word is, with the customer’s power goals in mind, Golen felt that it was a solid combination that the owner won’t have to worry about too much.
“The big issue with these things, any of these LSs, when you get big cubes, big heads that kind of thing, is the intake you’re using,” Golen said. “They are very sensitive to that kind of restriction. So you could have a great intake on it, but if it’s a stock-style intake, they’re probably going to struggle to keep up at this power level. So, that’s really the deciding factor in power production on one of these.”
Hitting The Dyno
And as if to confirm Golen’s statement, once they got the 502 on the engine dyno the engine made great power but just a little shy of what they typically see. “We ran it with the Hogan intake on there and it made 786 horsepower, which was OK, we were hoping to make more,” Golen lamented. “And now he has decided to purchase a single-plane intake with a big four-barrel throttle body. That should easily take us into the 800-horsepower range.”
Now, to us, 786 naturally aspirated ponies and a whopping 708 lb-ft of torque is nothing to sneeze at. But, understandably, when you’re that tantalizingly close to the 800-horsepower range, you’ll do just about anything to break into it. Also, let that power number sink in for a while. This is a naturally aspirated small-block that is making power levels that would make any turbo LS guy think twice. Not only that, but there is no lag time or special consideration to take into account with a mill like this — unless you mean the massive, overwhelming amount of torque this thing makes.
Though a naturally-aspirated build might not be in vogue these days, to us, they harken back to the early days of hot rodding when bigger was almost always better. Plus, who doesn’t love big-block power in a small-block package? And, if 800 isn’t enough, Golen equipped the mill with a little extra insurance via a Nitrous Express direct port system. Either way, we think this is one build small-block and big-block (Mouse and Rat) fans can all agree is one killer combination.