A Look Inside The Most Powerful N/A Nissan VQ-Series Engine Ever

Perhaps the Nissan VQ-series engine doesn’t get the credit it deserves. While it’s not known for making dragster-levels of power as easily as a VR38DETT, it’s still a stout, light, and compact engine with plenty of potential. One brave privateer racer wanted to explore the limits of this oft-derided V6, and after a year of restricted running in Koni Challenge with his 350Z, he turned it into a sprint-race and time-attack car. No longer shackled by stringent rulebooks, he pushed the VQ engine to its limit.

With the handcuffs removed, Sasha Anis began to explore the VQ’s potential, somewhat conservatively. After reaching the limits of the VQ35DE, Sasha decided to install a VQ35HR — a rare version of the VQ with high-flow heads, among other improvements.

The first iteration of his HR engine used a VQ37 crankshaft, VQ35HR heads, JE Pistons high-compression pistons, 53.5mm intake trumpets, and Jim Wolf Technology cams. The package was enough for a reliable 413 horsepower at the rear wheels and a glorious bellow at its 9,000-rpm redline.

At those high engine speeds, it’s not surprising that a factory connecting rod eventually failed and punched a hole in the side of the block, which left the starter hanging by a wire. Believe it or not, the engine continued idling and had oil pressure, even with a windowed block! It was only due to the missing starter that the engine wouldn’t start again.

Anis considered his options. One professional team offered to sell him a race-proven, 410-whp VQ37 — the engine from the 370Z — for a fantastic deal, but Anis decided to take a different route. He and some of the bright minds at Jim Wolf Technology were talking about a prototype 4.2-liter race engine for almost three years, and Anis felt this was the right time to try.

The naked engine, only clothed in heat shielding and ducting, screams bonafide racing car.

The objectives weren’t set in stone, but Anis knew he wanted to avoid forced-induction. In a front-engine, front-heavy car, adding roughly 70 pounds with a turbocharger and the ancillary coolers wouldn’t jive with his vision for a well-balanced road racing car. “It would be too easy, it wouldn’t have the right powerband, and it would have heat issues,” Anis admits. This engine had to be pure, revvy, lightweight, powerful, and atmospheric.

Indeed, what Anis sought was something nearing a factory-built GT3-class engine. He knew he’d have to get creative to reach his goal with limited resources and a fraction of a big team’s budget.

Asking for Aid

Though Jim Wolf Technology doesn’t always focus on professional racing, they had a great deal of experience with race-spec VQ engines prior to stepping in with Anis’ build. Back in the heyday of Grand-Am racing, Nissan Motorsports requested Jim Wolf build camshafts for its 350Z race cars.

This gig led to JWT building engines for some of the 370Z racecars in IMSA Grand Sport from 2011 to 2015. Because Jim Wolf didn’t have the time to engineer a high-lift solution to suit the Variable Valve Event and Lift (VVEL) system in the VQ37, instead, they decided to build a VQ37 with heads from the non-VVEL VQ35HR. Some might see it as a step backward, but the relative simplicity of the VQ35HR heads meant greater reliability, less weight, and no loss of performance on the track.

Meanwhile, Clark Steppler and Jim Wolf were involved with Anis’ efforts for some time. Just after Anis retired the car from professional racing, Steppler stepped in and ground a custom set of cams for Anis’ VQ as part of a camshaft shootout for Modified Magazine more than a decade ago.

The JWT cams won handily, and a partnership was formed then and there. “We were given the information on the competitors’ cams and strove to do our best within the constraints. These weren’t race cams, but just S1 street cams, and we still made 400 horsepower,” said Jim Wolf proudly.

That auspicious outing encouraged them to push their partnership through the years. Eventually, they started to outline goals for an ideal VQ powerplant organically. The salient question in their conversations was, “How could we make Porsche GT3R-level power?” As one of the most impressive naturally-aspirated engines made, with a similar displacement, trying to match the Porsche’s 550-odd horsepower with their modest budget was an ambitious goal.

Relatively compact, the custom VQ engine helps Anis near his ideal weight distribution of 52-percent, front, 48-percent, rear.

Fortunately, there weren’t any regulations to limit development, which had all parties losing sleep over the possibilities. As Wolf elaborates, “Most interesting was that we were given a blank canvas on an aging motor. We could push it to the limits, and we had an intelligent, determined, talented driver/client who could see things through. Profits be damned!”

They started by addressing the weak points of the engine. Through their years of racing the engine, JWT discovered that the production crankshafts eventually crack. So, they called in the experts at Bryant Racing to design a Chromoly steel crankshaft for their VQ37VHR block. Steppler also made a special version: one which increased the stroke to 96mm and the displacement to about 4.2 liters — 4,160cc to be exact. The crank sat on the shelf for years, begging to become the centerpiece of an extraordinary engine.

Adding Slipperiness

With only a moderate amount of displacement, they had to try everything in their power to achieve those numbers. One objective was minimizing friction, as it appeared to be a significant limiting factor in previous builds, showing itself in the form of high oil temperatures and poor BSFC at high-RPM.

With help from JE Pistons, they designed a custom two-ring piston for this purpose. By lacking the typical middle ring, this design came with its share of drawbacks. “There’s only so much of the bottom of the piston skirt you can pull out of the bottom of the bore before you start having issues,” says Steppler. They got around this problem with the two-ring design, which has its skirt begin just underneath the ring groove. With real estate at a premium, these were the types of considerations in component design they had to make to reach their goal.

One downside to this two-ring design is the loss of the oil-scraping function usually performed by the middle ring. Since the engine already had a Dailey Engineering scavenge pump mounted directly to a Dailey oil pan — which causes lower-than-atmospheric pressure in the crankcase — Anis and Steppler were confident the two-ring solution had a good chance of working.

“This setup has the effect of raising the pressure differential downward across the piston rings in an off-throttle situation, which is when the oil transfer is most likely,” notes Steppler. On top of all that, they used Total-Seal Gapless low-tension piston rings and coated the skirts in Swain Tech‘s PC9 polymer coating. Pretty slippery stuff.

King Engine Bearings provided the main and rod bearings for this project — both coated in their XPC material.  Though King didn’t produce bearings for the VQ, covered in the low-friction XPC material before, these custom bearings suit the custom internals. In fact, the main and rod bearings are the same sizes as those from a Nissan VR38DETT and a Honda K20, respectively, so they were able to get the XPC-coated versions.

A Tight Squeeze

“We were lucky to make it all fit within the stock dimensions,” says Anis. The massive crank made packaging a bit challenging. Everything, from the oil squirters to the block itself, had to be massaged to fit the oversized crank. The valve reliefs in the pistons are extremely deep to accommodate the variable intake cam timing, and the ring grooves in the piston are up as high as they can be relative to those big pockets.

The pistons come down right to the oil squirters. They actually required some small notches to avoid hitting them. The crank and rod bolts come dangerously close to the dry-sump pan, and it’s just good fortune that Bill Dailey designs his dry-sump pans with large-stroke cranks in mind.

Aiming for maximum cylinder sealing, they performed the valve job with the head bolted to a jig to ensure less deformation and valve leakage once the engine was fully assembled.

The head wasn’t straightforward, either. The team at JWT planned for a prototype intake camshaft, but it required larger custom valve buckets to prevent the camshaft from running off the edge of the bucket. Aside from the aforementioned avoidance of VVEL, the nice part of sticking with the VQ35HR head is it features a Direct-Action Mechanical Bucket (DAMB) design and no rocker arm system.

“That means, even at high revs, there’s no chance of rockers going flying. Plus, the system is quite lightweight and allows for high-revs, without excessively large valve springs,” says Anis.

To accommodate the cams’ larger lobes, they machined grooves in the head and valve covers to offer more clearance. The 14.8:1 compression ratio and tendency to run pump fuel meant they had to choose their cams wisely. “You can pair long duration with high compression,” adds Steppler. “With Canadian 94-octane fuel and a race gas octane booster, there’s still good knock resistance.”

Maximizing Airflow

Continuing the theme of “bigger is better” into the cylinder head, oversized Supertech 38mm lifters on the intake side mean more airflow capacity for aggressive cam profiles, while the DLC coating means less friction. On the exhaust side, they didn’t need to generate as much lift, as the stock 34mm lifters produce peak flow at lower lift.

All said and done, this monstrous engine makes a whopping 537 horsepower and 410 lb-ft of torque — making it the most powerful naturally-aspirated VQ engine in the world. Designed for road racing, the engine makes a usable 350 lb-ft of torque at just 3,500 rpm — and it’s planned to be even torquier with the usage of new and exciting technology.

Anis deliberated between different trumpet sizes for the engine’s individual throttle bodies and eventually decided on the 57mm trumpets for the best top-end power.

Going Greener

There are plenty of qualities distinguishing Anis from the typical engine tuner. Not many professional tuners can wheel a racecar quite like Anis can, and even fewer have a vested interest in developing EV technology. In addition to running OnPoint Dyno, Anis recently started another business catering to the modification of Teslas and other EVs. It’s a niche market, without a doubt, but Mountain Pass Performance keeps the hot rodder’s dreams alive in a rapidly changing world.

In an attempt to use the skills honed in both businesses while pushing the VQ further than anyone, he’s taken on another Herculean task. Much like with the VQ build, he’s brought in some very capable people to help him forward.

Two companies are assisting in the build, the first of which is MoTeC. Through his tuning business, Anis is well-versed with the MoTeC ECUs and motorsports electronics — so much so, that MoTeC elected him to be its Canadian distributor. He plans to use his MoTeC expertise to control an electric motor, which he’ll fit to the VQ.

The motor will come from a Swiss company called PhiPower, which produces the compact powerplants for Formula E. In addition to adding roughly 200 horsepower, the motor’s additional 45 pounds shouldn’t upset the car’s weight distribution. In fact, Anis plans on mounting it in the center of the car, right in the transmission bellhousing, then removing the alternator, starter, and clutch to offset the weight added.

The batteries, sourced from a BMW i8, are some of the few light enough to fit Anis’ goals. Six of them will be used to provide the extra 200 horsepower he’s after. The electric motor will take the place of the old clutch and flywheel, accept the combustion engine’s power, and send it back through the Xtrac sequential transmission.

To keep the weight distribution ideal, Anis will mount the heat exchanger and batteries at the rear of the car. The inverter is an item from Cascadia Motion, who builds inverters for modified hybrid hypercars and even Formula 1. As with everything on the combustion side of things, he’s only using motorsport-grade products with this unique powerplant.

Uncompromised and stretched to its limit, this barking V6 demonstrates what an ambitious and ingenious privateer team can do when it’s free from regulations. They are driven by a bit of underdog enthusiasm, and keen on getting every iota of performance out of the stout and capable powerplant. With performance that rivals some of Porsche’s best, this singular creation is an inspiration to us all.

“The motor is like artwork. I’m almost sad to hide it in the bellhousing,” said Anis.

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About the author

Tommy Parry

Tommy Parry has been racing and writing about racing cars for the past seven years. As an automotive enthusiast from a young age, he worked jobs revolving around cars throughout high school, and tried his hand on the race track on his 20th birthday. After winning his first outdoor kart race, Tommy began working as an apprentice mechanic to amateur racers in the Bay Area to sharpen his mechanical understanding. He has worked as a track day instructor and automotive writer since 2012, and continues to race karts, formula cars, sedans, and rally cars in the San Francisco region.
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