Does the name Katech mean anything to you? If it doesn’t, it should. Katech has been powering some of GM’s top racing programs, including the Corvette Racing team, to wins for many years. Corvette Racing alone just recently racked up their 99th victory in program history and will soon make it an even 100; an outstanding record considering the highly competitive GT class in which the Corvette competes.

Katech-powered vehicles have put the beat down on almost everything the world has to offer, from Aston Martins to Dodge Vipers. Along with Corvette Racing, Katech has taken on all challengers and has seen more than one competitor completely fold in the wake of their dominance (We’re looking at you Dodge Viper).

Not only has Katech powered the take-no-prisoners Corvette Racing team, they also have powered the likes of World Challenge Cup Cadillac CTS-V.RS and Grand-Am Pontiac GTO.Rs. They have powered six 24 Hours of Le Mans wins (five of which were 1,2 victories), an overall victory at the Rolex 24 at Daytona in 2001 and four straight American Le Mans Series championships. GM Racing’s Katech-built LS7.R was also named 2006 Global Motorsport Engine of the Year.

And Katech’s chops don’t end at the track. You may remember the Pratt & Miller developed Corvette C6RS—if not you have some Googling to do— it features a 600-horse, LS7-based, 500 ci engine developed and built by, you guessed it, Katech. 

What we’re trying to say is that when it come to engines—winning engines specifically— Katech knows their stuff and they have combined all their know how and years of experience to produce the most powerful naturally-aspirated LT1 in the world.

When the General first released the C7 back in 2014, Katech immediately set to work to develop a 427 ci engine capable of turning a base-model ‘Vette into the equivalent of the previous generation’s ZR1.

An MSD Atomic Air Force intake manifold and a Katech-exclusive 103mm throttle body helped bump the Street Attack 427 over the 700-horsepower mark.

“We knew there was a lack in GM’s line up with the absences of the 427,” said Jason Harding, director of aftermarket operations at Katech. “And some people just prefer that naturally-aspirated feel.”

After the Grand Sport was released, they knew they had the perfect platform.

“This will allow a customer to basically have a naturally aspirated Z06 when combined with the Grand Sport,” Harding said.

This engine won’t just make any Grand Sport a Z06, it will make it a Z06-beater.

Katech has taken it’s years of invaluable experience and put it to good work in this stout mill. Starting with a standard LT1, Katech throws a longer 4-inch stroke at it with a Callies forged 4340 steel crankshaft, bringing the total displacement to 427 ci. Callies forged h-beam connecting rods link the crank to the Diamond forged 2618-alloy slugs. Katech CNC-ported heads, featuring high-lift valve springs and titanium valve spring retainers, speed fresh atmosphere into the cylinder where the compressions has been bumped to 12.5:1.

A custom-ground Katech bumpstick, governed by a VVT limiter, tickles the valves. An MSD Atomic Air Force intake manifold handles the induction duties and is fed by a 103mm billet throttle body. Modified direct-port fuel injectors handle the added fueling requirements while the stock injection pump keeps them suppled with fresh octane.

Take a look at the two stage pump powering the Street Attack 427’s dry-sump oiling system.

This all equates to 700 horsepower and 620 lb-ft of torque of naturally-aspirated goodness, exceeding the current Corvette Z06’s output by 50 horsepower.

“Not only does the Street Attack 427 make 700 horse, it makes at least 600 lb-ft of torque from 4,400-5,700 rpm,” Harding said. “In fact, it made at least 500 lb-ft of torque everywhere we tested it.”

With those kind of impressive numbers you would guess that Katech’s LT1 would be a no-holds-barred build, but you’d be wrong.

“It does have a larger cam but you would be amazed at how civilized one really is,” Harding said. “The cam still provides great vacuum and drivability.”

Now that you’ve probably decide that you probably can’t live the rest of your life without getting your hands on one of these things,  you have a couple of options: Katech will gladly install one of these beasts in your C7 at their facility in Clinton Township, Michigan OR you can order this bad boy as a crate motor. However, if ordered as a crate motor, it will require some dyno tuning at your local speed shop.

So, if you’ve been missing the LS7 and hoping that GM would step up and release a new version with direct-injection and variable valve timing then look no further; it’s here.