In 1968, Chicagoland drag racer Ted Borowski started a hardcore race engine building business. Borowski earned a reputation as the go-to guy for big power. By 1998, Ted won the UDRA Nitrous Pro Stock crown. Sadly, however, Ted passed away in 2003. The engine business languished, shop tooling was now aging and quality went downhill.
In 2010 Ken McCaul purchased the business, Borowski Race Engines, knowing full well what the issues were. He invested heavily in new high tech CNC machinery along with a precise inventory control system. Case-in-point is the Rottler F68A automated engine machine center. It can bore, drill, tap, mill, surface deck, true the lifter bores, mill a block for stroke clearance, drill the cam bore, line bore the mains and so on. This setup allows the machinist to hold all dimensions to + or – 0.0001 inch. And this is just a thumbnail sketch. The complete operation is teeming with new high tech machining equipment.
McCaul’s shop is primarily a race shop that builds drag race, circle track and marine engines. Going into the business, Ken knew he would have to keep on top of what was hot, and it should be no secret to anyone reading this that the Chevy LS was (and still very much is) “hot.” Equally important, Ken knew that big power, reliable and streetable LS combinations were attainable. As a result, he focused in on those engine packages.
And that’s really the story here. Over the next four weeks, we’ll take a look at two of Borowski’s most popular powerhouses – a 2.9-liter Whipple supercharged engine along with a King Kong 4.0-liter Whipple blown example.
The biggest power 2.9 setup is based upon a Dart LS Next block. This block offers a full priority main oiling with a stepped main oil gallery. As most know, the block is a hybrid design that isn’t Y-block skirted. Instead, the bottom end is much the same as a conventional Gen 1 small block. This is a fix for LS windage problems and also allows for the cylinder barrels to be lengthened by 3/8 inch (perfect for long stroke engine combinations).
McCaul says, “The LS Next block is the first significant change in the bottom end architecture of the LS engine platform. By eliminating the ‘Y-block’ design and utilizing conventional style main caps and oil pans, Dart has addressed the problems resulting from the LS engine’s separated crankcase bays. Windage is greatly reduced, resulting in increased power and improved lubrication.
“Conventional style 4-bolt steel main caps are used. A 5/8-inch thick full deck design is utilized for superior strength, with six head bolts per cylinder to provide secure clamping. Dart’s priority main oiling system ensures high rpm reliability and includes provision for oil restrictors in the lifter valley.”
Downstairs, the crankshaft is a 4.00-inch stroke forged Callies Dragonslayer coupled with 6.125-inch (center to center) Callies Ultra Connecting rods. The 10.25:1 pistons are custom Diamond piston forgings. The ring package also comes from Diamond (Pro Select AP Steel Rings). The wrist pins are also from Diamond – they’re heavy duty, 0.200-inch thick examples. Clevite HN Rod and HX Main Bearings are used exclusively.
The LS Next cylinder block accepts a stock LS front cover along with a Cloyes hex-adjust adjustable timing set. The splayed mains accept a custom Borowski Racing-engineered aluminum oil pan along with a custom pickup to provide the correct sump pickup depth. The oil pump is a Melling job fitted with a custom relief spring so that they can obtain a desirable 30 PSI at idle and 52 PIS at 7,000+ RPM.
The camshaft is a custom designed hydraulic roller from the folks at Bullet. Specs for the cam grind are proprietary. Let’s say it’s stout! Meanwhile, the tie-bar hydraulic lifters are off-the-shelf matching pieces from Bullet.
Next issue, we’ll move upstairs and have a look at the top end of the engine. Needless to say, it’s impressive. Watch for it.