Suppose you are a Chevy fan, and you must have a gloriously powerful engine for your Camaro on short notice. Let’s also suppose that it has to be a turnkey deal and small enough to fit wherever a traditional small-block would fit. And here’s the kicker: You just won the lottery, and price is no object! What would you do? Where would you turn? These days, there are many engine builders who have mastered the craft of assembling a precision built engine, and with so many insane speed parts available for GM’s Gen III, Gen IV, and Gen V LS and LT powerplants, it might be hard to pin down a good place to start. We have answers, but first we’d like to explain why the cost seems so high.
Stock vs High Performance
If you took a sneak peek at our top five engines below, you might ask yourself why these engines are so expensive when they pretty much look like any ordinary LS crate engine—their highly polished exteriors notwithstanding. That’s a fair question, and in a nutshell, they’ve been touched a lot more than usual and by people who know how to do that sort of thing. Extending the useful power output of any internal combustion engine means every machining operation and every clearance must be checked and double checked. Tolerances are very slim when the power goes up, and what might be acceptable with a 300-hp engine isn’t going to cut it at 1,000 hp. Moreover, when boost is involved, some engine specs, such as the piston ring end gap, need to be modified to keep catastrophic engine damage at bay. The people who build engines at this level don’t grow on trees, so expect to pay for that.
Related Story: 10 Cheap LS Crate Engines Under $5,000
Strength is also an issue, and nearly everything exposed to heat and pressure requires some degree of reinforcement. At the level we’re starting at, there are few parts coming from the GM parts bin other than the engine block, and the ones that are involved are very special GM parts that can’t be found in the ordinary truck engine. At this power level, if you want it to survive longer than one Hail Mary down the track, it better have the best stuff out there. Lastly, making this kind of power requires gigantic airflow, and in this regard, there’s no substitute for superior cylinder heads combined with boost. (An easy-to-install crate engine format pretty much counts out turbocharging, but turbos would also be viable provided there’s ample fabrication resources and time.) Let’s crack open the vault and see what’s inside.
Pace Performance—BluePrint engines 427-cu in. 750-hp LS3
Warranty: 30 months/50,000 miles
Shipping: Free (48 contiguous states)
Part No.: PSLS4272SCT
We’re starting at the low end with BluePrint’s 750-hp powerhouse based on a new blueprinted LS3 block. Beyond that, everything else is upgraded including a new internally balanced, forged 4.125-inch stroke crank, forged 10.8:1 pistons, forged 6.125-inch long H-beam rods, BluePrint’s race-spec cylinder heads (2.165-/1.600-inch valves), a big hydraulic roller camshaft (.624-inch lift, 239-/255-degrees duration, 114-degree LSA), and a positive-displacement supercharger in the style of Eaton or Whipple. The price on this LS3-based 427-cubic-inch crate engine is regularly $18,999 (most outlets had this same price the week of our research), but Pace Performance has stepped up by cutting almost $2,000 from your bill (price is for a new unit that was used on display), definitively putting them on our list.
Summit Racing—Chevrolet Performance LT5
Warranty: 24 months/50,000 miles
Part No.: 19417105
When OEs decide to get into the crate engine business, they are hard to beat, and Chevrolet Performance’s 755-hp LT5 crate engine—lifted straight out of the 2019 Corvette ZR1—is as bulletproof as they come. In your favor is the fact that out of all the engines here, the LT5 is the one with the most development and testing under its belt. As a Gen V design, it features direct injection (as well as staged port injection) putting it on the bleeding edge of IC technology. It provides 755 hp and 715 lb-ft of torque without breaking a sweat, thanks to an improved (relative to the LT4) 2.6-liter Eaton supercharger providing 9 psi of boost and a smog-friendly hydraulic roller cam (.551-/.524-inch lift, 200-/207-degree duration). With a forged rotating assembly, Titanium intake valves, and race-quality cylinder head airflow, you’ll feel confident that this engine is overbuilt. Note: the LT5 crate engine is common enough to be considered a commodity, so shop around for your best price. Also, a $250 mail-in rebate drops the cost to $18,561.30.
EBay Store—Prestige Motorsports 427ci Supercharged 800-plus HP
Cost: $25,999 (Buy It Now)
Warranty: 14-day return policy
Shipping: available, calculated from Concord, NC
Part No.: L427-B1-W29
Next up is a unit from Prestige Motorsports’ family of Power Adder Series engines (seller name “prestigemsports”), which are offered for sale on the company’s eBay store. This combo caught our eye because it cranks out over 800 hp from 427 cubic inches, thanks to a fortress-like LS Next cylinder case from Dart, a 2.9-liter Whipple supercharger, and a forged 4.00-inch stroke crank and 9.5:1 forged pistons. Prestige goes the extra mile by making it a turnkey deal with a Holley Terminator X EFI system, a complete ignition system, and a Holley accessory drive. From the looks of it, Prestige has built plenty of extra strength into their Power Adder Series crate engine, so it can be run on pump gas and take the typical beating that many street machines dish out.
Mast Motorsports Black Label 900HP Supercharged Engine
Warranty: 30-day return policy for unused merchandise
Shipping: available, calculated from Nacogdoches, TX
Part No.: n/a
Over the last 14 years, Mast Motorsports has staked out a claim to the high-end LS market, always working just a little bit harder to have a leg up on the competition. And though it has mattered little to the budget-oriented enthusiast hoovering the scrapyards, Mast’s regular customers have certainly noticed. Early on, Mast recognized the value in developing their own line of high-flow induction components, such as cylinder heads, camshafts, and intake manifolds, and as a result can now offer some of the highest horsepower crate engines anywhere. The company’s Black Label 900-hp crate engine benefits from all that work; with similar hardware to the Prestige Motorsports entry above (forged crank, rods, pistons, race-ready block, 427 cubic inches, accessory drive system, 2.9-liter Whipple blower), it is the Mast Black Label LS3 280 cylinder heads that push output up to the 900-hp mark.
EBay Store—1,275HP 427ci Dart LS Next With Supercharger
Cost: $34,500 (Buy It Now)
Warranty: 1 year / 12,000 miles
Part No.: eBay item number 142838554157
For about the price of a new Camaro SS, you can click “Buy It Now” on eBay and have Borowski Race Engines send you one of their 1,275-hp LS crate engines (seller name “borowskirace”). Like our prior two crate engines, Borowski builds on the strength of Dart’s LS Next cylinder case, using a Callies forged crank and rods with Diamond forged pistons, only this time Borowski slid his finger to the bottom of the page picking Whipple’s biggest blower—a 4.5-liter behemoth that stuffs 20 psi through a pair of Dart Pro 1 LS3 heads with a CNC valve job. (Cam specs are not given but state a Comp Cams LSR Series hydraulic roller.) Borowski provides this crate engine with a full accessory drive, as well as two sets of blower pulleys: one for the street (pump gas) and one for high boost and race fuel.