Our Castrol Syntec Top Shop Challenge Near-Winner Spits Our 867 Horses. Here's How:
Ahh, the perks of working at a car magazine: getting paid to do what we love, right? If that means sitting in front of a computer 12 hours a day, 6 days a week for half the month trying to meet deadline - whilst filtering through email barrages of "fantasy rod" pill offers (hint: not an engine part) or queries from kids in Alabama named Toby regarding H22-to-Tercel swaps... then yes, this is a job to die for. And by "die", we mean spending the remaining two weeks of the month wrenching into the nights on cars that aren't yours, driving seven hours across the desert, to stand in the sun for 13 hours because the plane ticket you were promised "fell through". But at least there're plenty of models to kick it with, right? Sure - for the freelancers; we're too busy rolling around on the ground, shooting feature cars to snap them. Remember that hot desert sun? Chances are we were lugging around a camera and/or loads of equipment in it. Don't think you'd be getting and hottie's number after 13 hours of that.
So, please, take our word for it when we say that anyone who breaks our daily routine quickly becomes a good friend. And for the last six months, the Castrol Syntec guys have straight-up been our homies, because the monster SR20DET laid out on the pages in front of you is resultant of their Top Shop Challenge - a competition inviting yours truly, along with six other automotive publications, to try our hand at commissioning the build of the best streetable engine ever built. Complimentary parts, full access to the best engine building and tuning shops in the industry, and a genuine budget of both time and money to use toward building something that could break records, and garner fame, fortune ($25,000 plus bonuses to the winning team) and maybe a few hotties all at once? We'd do it twice, if we could.
Joining forces with renowned speed shop G-Dimension, of City of Industry, Calif., Nissan's SR20DET was designated our weapon of choice, honed into the monster you see, and sent into battle against six of the world's most powerful RB-, VG-, F-, 4G-, 7A-, and, um..."small block"-stamped contenders, to fight for the ultimate title. This, madams and sirs, is how legends are made... Hotties, take a number.
It's often stated that air, fuel, and spark are all that's needed for an engine to produce energy. But to produce any significant amount of it, two additional variables must be considered: the ability to manage the proportions of each, and the ability to hold and transfer the energy released. We knew that if this SR had any chance against the competition, it would need to be able to produce and transfer about five times more power than its factory design was meant to handle; meaning that drastic reinforcement would be needed in all areas, beginning with its power-holding faculties. And to kill two birds with one stone whenever possible, read on to learn of some interesting side benefits of the parts we chose.
90mm 8.5:1 Compression Forged Aluminum Pistons
Switching to a 90mm piston increased our SR's bore 4mm for each cylinder, bringing total displacement from 2.0L to more than 2.1L without affecting its stroke and rev-ability. CP Pistons also allow for tighter-than-normal cylinder-to-piston tolerance, due to their high-silicone aluminum alloy that expands less at operating temperatures than their competitors'.
X-Beam Connecting Rods
In addition to increased strength, our Pauter "X-Beam" rods free up power by decreasing windage, compared to the conventional "I-beam" design of other rods that have two broad, flat faces on their forward-moving sides.
GTiR-spec SR20DET main And Rod Race Bearings
Though all SR20DETs are essentially the same engine, the FWD version from the Nissan Pulsar GTiR boasts wider rod bearings, and more porous main bearings, that distribute load and promote oiling better than factory RWD SR20 equipment.
Ductile Iron Sleeves
The factory closed-deck design of the SR20DET is very stout, but its original cylinder sleeves don't lend well to aggressive over-bores. Our Darton Ductile iron units do, while holding more pressure.
-Block machining and finishing
-Sleeve installation, 90mm bore and hone
-Main journal line bore and oil groove machining
-Crankshaft balancing and polishing
-Block deck surfacing
All the time and money invested on an engine build-up could just as easily be flushed down the crapper if the services of an experienced machine shop aren't employed with the steps listed above. Each requires the use of specialized equipment that 99.9% of us do not have at our disposal, and craftsmen who 99.9% of us aren't. Do yourself a favor and don't skimp here.
SR20DET water pump, rockers, timing chain kit, re-build kit and master gasket set (not pictured complete)
90mm headgasket and 1/2-inch headstuds
Grace Under Pressure
More power means the detonation of more air and more fuel. Left to its own devices, no small-displacement, four-cylinder engine is capable of producing the amount of power needed to compete against larger engines with more cylinders. Through forced induction, we could essentially double our SR's displacement with each atmospheric bar (14.7 psi) of boosted air and fuel we crammed into its cylinders, provided they were cooled to ambient temperatures.
Because we were turbocharging, not only was the amount of air and fuel we could introduce into combustion an important point to mind, so was how efficiently the spent charge could escape the engine and spin our turbine. This custom-sized Garrett GT42R (sorry - specs remain a G-Dimension secret) features a turbine housing and wheel trim small enough to spool quickly, but large enough to provide adequate high-boost/engine speed exhaust gas flow to spin the compressor fast for big top-end power.
G&J Aircraft & Competition
-AN hose ends and adapters
-Stainless steel braided line (not pictured)
-Miscellaneous plumbing parts
-Liquid-To-Air Intercooler Fabrication
-321 stainless steel exhaust manifold fabrication
Building the ideal high-power race engine means you get to break some rules. Decreasing charge plumbing length reduces pressure drop and improves power, doubly so if you can combine it with an exhaust manifold that improves exhaust gas velocity to help spool a turbo more quickly. Battle Version front-man and Formula D drifter Alex Pfeiffer accomplished both tasks with these custom pieces that also happen to fit perfectly inside a 240SX engine bay.www.battleversion.com
-44mm wastegates (x2)
-50mm blow-off valve
Modified Q45 throttle body
While we were able to increase our SR20's displacement slightly, and forcibly introduce more air and fuel into it, it wouldn't have been enough to put it on par with giants like Lowrider's small-block Chevy once boosted. With all things equal, large displacement engines with more combustion events per revolution (more cylinders) always make more power than smaller engines... but things are not equal, and all their added mass becomes a limiting factor as these engines' speeds increase. Smaller engines with less rotating mass can easily spin to higher RPM, and we knew that making big power with our SR20 meant not only stuffing its cylinders with as much air and fuel as possible, but keeping it all moving at a much higher engine speed than the other guys.
-Solid Pivot Kit
-Rocker Arm Stoppers
Factory SR20 hydraulic lifters have a tendency to "bounce" over aggressive cam lobes at high engine speeds; so much so, that the entire rocker arm assembly they're a part of can completely break off and cause serious damage to cylinder head components. Replacing the factory hydraulic lifters with a Tomei Solid Pivot kit kept lifters firmly planted against lobes, and adding Rocker Arm Stoppers kept the assembly from lifting too far.
-1mm-oversized stainless steel intake and Inconel exhaust valves
-Bronze valve guides
-Double valve springs
-550cc primary fuel injectors
-1,200cc peak and hold secondary fuel injectors
Increased airflow requires increased fuel, and the amounts our SR needed at high boost were simply too far removed from what was needed at idle to be adequately supplied by only four injectors. Four 550cc primaries handle idling and low-RPM duty, while four more 1,200cc secondaries come online under boost, to provide all the fuel we could ever need.
Custom intake manifold fabrication
If you think you can modify an OE intake manifold to accept four additional injectors, a modified throttle body, and increased flow while still remaining strong under high boost-think again. Thanks, Stephen, for one of the baddest manifolds ever to grace an SR!
Ross Machine Racing
-Fuel injector bungs
-Custom fuel rails
-Velocity stacks and miscellaneous intake manifold parts
-Cylinder head porting
-Intake manifold port-matching
-Combustion chamber finishing
-Complete valvetrain assembly
Equally as important to a quality engine build as reinforcing its block to hold power, is machining its head and its periphery components to produce it. Don't just think you can order a bunch of parts and throw 'em together - having an experienced professional handle tasks like valve machining and seating, head porting, and manifold port-matching is one of the best investments you can make.
The most important ingredients in any significant engine build are experience and action. Parts and resources don't create a finished product; hard work does. For each step of our SR's build, we enlisted the help of only the best: Mark, Jay and Pat of the Mazworx crew; Dave, our cylinder head guru at HeadGames Motorworks; Mike and the Speed-O-Motive team; Battleversion front-man and fabricator Alex Pfeiffer; and finally, James and Leon Chang and Stephen Rhim of G-Dimension for their tireless hard work planning a battle strategy, arranging parts and services, reaching into their pockets for whatever fell outside budget, fabricating what could not be bought or bartered, assembling, wiring and tuning the SR in-house, and getting their hands dirty every step of the way. We absolutely could not have done it without their expertise and selfless dedication. Any hotties' phone numbers should be immediately forwarded to them!
With virtually every component of our engine replaced, removed, upgraded, or modified, we knew getting everything to work together wouldn't be easy. Our engine had grown in displacement, and had been added a vastly larger turbo, four additional fuel injectors, a completely re-designed intake manifold and throttle body, a 5-bar map sensor, and its MAFS had been removed. Needless to say: throttle position, fuel pressure, injector duty, manifold pressure, ignition timing-virtually all maps needed to run our engine-had to be constructed from scratch by master tuners, and an advanced engine management system was needed to handle it all. On top of that, a grip of advanced ignition components would be needed to produce a stronger, more predictable spark to light the mix we were trying to regulate. Sigh...
-CDI Pencil Coils
-Uego Wideband O2 sensor
-Stand-alone engine management system
The ability to control virtually every aspect of engine function, and work perfectly with complimentary AEM electronics, while providing an intuitive starting point for tuners to work with; AEM's EMS manages the world's most powerful SR20DET race engines and street cars alike; why would we use anything else?
Twin Fire Ignition
Higher cylinder pressures from increased air and fuel require a much more powerful spark to ignite. AEM's Twin Fire unit can fire multiple sparks per event, and offers the fastest-available capacitor recharge at high RPM, to help maintain consistent combustion from idle to redline.
Peak And Hold Injector Driver
We're using eight injectors that flow five times more fuel than the factory four. Something was needed to control this mess.
Heading into any competition unprepared is never a winning strategy, especially when building engines nearly from scratch. Though the final battle would be fought at Speed-O-Motive's engine dyno, it was up to the G-Dimension crew to get the SR tuned and ready prior to that, which meant temporarily installing it in one of their drift cars and hitting the chassis dyno. Hearing the ghost in the machine roar to life after months of hard work, days of final preparations, and a few moments of uncertainty, sent chills through the spines of all who witnessed it. After some tweaking from Leon and Stephen, and some fine-tuning from Koji-san, the tired S13 was literally sliding off the rollers, with the monster SR powering it in need of a more suitable mechanism for measuring its worth.
The Moment Of Truth
Castrol Syntec's Top Shop Challenge is over, and the results are in this issue's insert. Go to importtuner.com for an all-inclusive recap of the competition, including video of our shakedown chassis dyno runs, and some final tuning on Speed-O-Motive's engine dyno the official day of competition. We might even throw some video of the other guys in there, too... blowing up, stalling out and posting far inferior numbers to ours, of course!