The Chevrolet Performance LS376 crate engine has been with us for years now and for good reason. When it comes to bang for the buck there is no beating it; that was, until now. Late last week, Chevrolet flew us out to their newly revamped Global Propulsion Systems center in Pontiac, Michigan to get a sneak peek of their newest crate engine before it breaks cover at SEMA, and we are here to tell you that they have done it again with this: the LT376.
Much like its predecessor, Chevrolet started with the LT1 out of the Camaro SS and Corvette, then they slipped a much hotter camshaft into it. Gone is the variable valve timing and Active Fuel Management, sacrificed in the name of performance and piston-to-valve clearance. However, the mill still retains its high-tech direct-injection system and all other LT1 components, making it one of the most technologically advanced crate engines Chevrolet Performance has ever offered.
The new LT1 Hot Cam, which specs out at 228-degrees of duration on the intake and 248 on the exhaust with a .577-inch lift on both valves, all ground on a 112-degree centerline, is a fairly aggressive piece that we can tell you from personal experience has a nasty little lope to it. The bumpstick is installed 6-degrees retarded and features almost 12-degrees more duration on the exhaust side than its ASA forebears, with a greater overall lifter number; which gives the mill more power while the revised cam timing keeps the power production within a reasonable RPM range.
“Countless hours went into developing the cam specifically for this application,” said Rocko Parker, a performance engineer at General Motors. “The LT1 is quite different in the way it responds, so we started from scratch with this cam.”
Use Your Head
Unlike its predecessor, however, Chevrolet didn’t just stop at the cam. The LT1’s cylinder heads have been CNC-ported to outflow the stock casting by a substantial margin, but still retain their stock 58 cc combustion chambers. Combine them with the more aggressive cam grind and you come up with a recipe for a 535 horsepower crate engine that you can buy directly from GM with a warranty – a two-year/50,000-mile warranty to be precise.
“The runners on the stock heads are already fairly large, so they already flow really well,” Parker said. “But there is still power to be found with the porting that we’ve done to them.”
While we didn’t get the exact flow specifications on the new CNC-ported heads, we can tell you that the intake was flowing in the 340 to 360 cfm range, while the exhaust was approaching 280 cfm. That means that the exhaust ports flow more volume than the original 241 casting LS1 heads. The heads retain their stock 2.13-inch intake and 1.59-inch exhaust valves.
“We’re getting to the point where the intake side flows so well, the engine needs a little more time to get the exhaust gases out,” Parker explained. “That typically means that these engines favor a little more duration on the exhaust side to give it time to do that.”
The new heads represent the next technological evolution in affordable CNC-ported heads offered directly by Chevrolet Performance. Their CNC-treated LS3 heads are some of the most affordable, highest flowing on the market, and these new LT1 components look to continue that trend. With flow numbers like that, we’d love to see what a set of these would do on something with a little more displacement to take advantage of all that air (stay tuned for that).
The rotating assembly is unchanged from the base LT1 and consists of a forged steel crankshaft, powder-forged metal connecting rods, and eutectic pistons. Six-bolt nodular iron main bearing caps keep the rotating assembly in place and the air/fuel mixture is squeezed to the stock 11.5:1 ratio.
In case you didn’t catch it the first time, all of this amounts to 535 horsepower accompanied by 470 lb-ft of torque right out of the box.
Heads And Cam Kit
But what if you have a stock LT1 and want the added power but don’t particularly see yourself buying a crate engine anytime soon? Chevrolet Performance hasn’t forgotten about you and now offers both the heads and cam individually or in a kit to bring your Gen V mill up to LT376 specifications. However, keep in mind that these are performance-oriented pieces and will void the original GM warranty if installed.
The kit consists of the hot cam, CNC-ported cylinder heads, four lifter trays, and eight lifers, which put the kibosh on your Active Fuel Management and variable valve timing—but in our opinion is very, very worth it; especially if your main focus is on performance and not fuel economy.
The LT376 is a potent addition to Chevrolet Performance’s impressive array of crate engines and we are positive that we will be seeing these on the street in no time—possibly in one of our project cars.
Connect & Cruise
New to the line up as well is the LT1 Connect & Cruise. The package not only comes with the 460 horsepower, 465 lb-ft of torque “base” LT1, but also gives you all of the necessary wiring harnesses and controllers to have it working flawlessly between the fenders of your favorite ride in no time.
There isn’t an easier way to get everything you need to get a Gen V engine up and running. GM has truly made the entire system plug-‘n-play.
Stay tuned to LSXmag.com for more 2016 SEMA coverage!