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LS3 Crate Engine - The New GMPP LS3

So What If You Can't Afford A '10 Camaro SS. You Can Still Own The Mill. Check Out The New GMPP LS3

By , Photography by , GMPP
GMPP LS3 Crate Engine
GMPP LS3 Crate Engine
The LS3 is a complete crate engine. You get the ignition, intake with injectors, throttle body, water pump, and even exhaust. It also comes with a Corvette oil pan. If you want the F-body pan, you'll need to order one separately or use the L99 6.2L engine from the automatic-transmission-equipped '10 Camaro.
GMPP LS3 Crate Engine
The LS3 is a complete crate engine. You get the ignition, intake with injectors, throttle

The LS3 Camaro crate makes the LS series of engines legit. Up until now, you had to either spend ahoy on the gigabuck LS7, be happy with the iron 6.0L and its weird truck accessory drive, or strip down a pricey LS2 Corvette to get the coveted factory 4.00-inch-plus small-block bore size. For about $6,500, the new Camaro crate engine packs a 4.065-inch bore and matching performance cylinder heads and makes 430 hp and 424 lb-ft from the factory. This thing is such a good deal, you have to pay attention.

The power potential of the LS3 comes from its ability to use the L92 cylinder head port design. We've tested this head before on a stock 6.0L and made 550 hp with a cam swap, so we know it works. We wanted to use this head on other LS-series engines like the LS1 (5.7L) or LM4 (5.3L), but the 2.165/1.59-inch valves require at least a 4.00-inch bore to clear the block and need the 4.065-inch LS3 bore size to be really happy. In addition to the base LS3, there are two variations of the LS3 also available. The LS3-based LS376 has a Hot cam and is rated at 480 hp. Add a single-plane GM intake and the ASA Hot cam, and GM claims the LS376 will make 515 hp and 469 lb-ft with a GM competition single-plane carbureted intake and a 770-cfm Holley. Remember, this engine is only 376 ci.

GMPP LS3 Crate Engine
The LS3 block is a direct replacement for the L92 found in the Escalade, Denali, '08-and-later Corvette, and now the '10 Camaro. It is made from 319-T5 aluminum and has a 9.240-inch deck height and 4.40-inch bore centers.
GMPP LS3 Crate Engine
The LS3 block is a direct replacement for the L92 found in the Escalade, Denali, '08-and-l

If you go for the base LS3, you get a cast-aluminum block with iron cylinder liners, six-bolt cross-bolted main caps, and the L92 heads. The cylinder liners are designed for the stock 3.600-inch stroke, but it is possible to go to 4.00 inches. With the maximum overbore of 0.030, the block has the potential for 421 inches using an aftermarket rotator assembly. The cam is a hydraulic roller with 204/211 degrees of duration at 0.050 with 0.551/0.522 lift. The heads have a 68cc chamber and with the hypereutectic aluminum pistons yield a 10.7:1 compression ratio, so the engine needs 92- octane pump gas. The intake and drive-by-wire throttle body are included, but you'll need to buy the GM pedal assembly. GM offers an LS3 controller to run the system in everything from a street machine to a street rod.

Head Flow We've tested the L92 port before on a different flow bench and our published numbers are slightly higher than the ones provided by GM below. The GM tests were performed with a 4.065-inch bore plate.

  • GMPP LS3 Crate Engine
    The crankshaft on the LS3 is nodular iron instead of forged steel like the LS7 or LS9. The main journals are 2.56 inches and the rod journals are 2.100. All 5.3L to 6.2L LS engines use 6.067-inch connecting rods made of powdered metal.
    GMPP LS3 Crate Engine
    The crankshaft on the LS3 is nodular iron instead of forged steel like the LS7 or LS9. The
  • GMPP LS3 Crate Engine
    If you are going to run a manual transmission, you will need a flywheel because the LS3 comes with a flexplate for the Corvette. McLeod offers a complete flywheel, clutch, and pressure plate to mate any early four-speed transmission to your LS-swapped car.
    GMPP LS3 Crate Engine
    If you are going to run a manual transmission, you will need a flywheel because the LS3 co
  • GMPP LS3 Crate Engine
    The cylinder heads make the LS3, and there are a few factory options to add more power. As delivered, the LS3 castings have the L92 port. To review, the LS1 has the cathedral port that is tall and thin and worked great for the small-bore 5.7L engine. The next design was for L92-powered trucks, LS3 (Z06) Corvettes, and the new Camaro. The L92 intake port is 260 cc and resembles a big-block Chevy rectangular port. According to GM numbers, it flows 294/183 cfm at 0.500 lift.
    GMPP LS3 Crate Engine
    The cylinder heads make the LS3, and there are a few factory options to add more power. As
  • GMPP LS3 Crate Engine
    The exhaust port is a standard LS D port, so your LS1 headers should work.
  • GMPP LS3 Crate Engine
    The LS3 head uses 1.7:1 rocker arms and beehive springs. Note that the intake rockers are offset to get the pushrod boss away from the intake port path. The head also uses a 15-degree valve angle as opposed to the standard Gen I 23-degree angle-the idea being, the less the valve angle is, the straighter the shot into the cylinder.
    GMPP LS3 Crate Engine
    The LS3 head uses 1.7:1 rocker arms and beehive springs. Note that the intake rockers are
  • GMPP LS3 Crate Engine
    Check out the huge 2.165 intake valve. The combustion chamber is 70 cc, giving the LS3 a 10.7:1 compression ratio, or you can use this CNC-ported LS3 head with a 68cc chamber.
    GMPP LS3 Crate Engine
    Check out the huge 2.165 intake valve. The combustion chamber is 70 cc, giving the LS3 a 1
  • GMPP LS3 Crate Engine
    The days of flat-tappet camshafts in factory small-blocks are gone. The factory cam has 204/211 degrees at 0.050 and 0.551/0.522 lift. The LS Hot cam has 15 additional degrees of cam timing on the intake and 17 degrees on the exhaust and has 0.525/0.525 lift.
    GMPP LS3 Crate Engine
    The days of flat-tappet camshafts in factory small-blocks are gone. The factory cam has 20
  • GMPP LS3 Crate Engine
    The LS3 intake is not like anything from the past. The injectors flow 40 to 41 lb/hr at 58 psi.
    GMPP LS3 Crate Engine
    The LS3 intake is not like anything from the past. The injectors flow 40 to 41 lb/hr at 58
  • GMPP LS3 Crate Engine
    Although you could use a factory harness from a...umm...wrecked Corvette or new Camaro, the best bet is the LS3 controller harness from GMPP. The downside is that it won't control the transmission like the factory harness, and so far, it is plug-and-play only. If you are running a manual transmission and a GMPP cam, you'll have everything needed to get the car running.
    GMPP LS3 Crate Engine
    Although you could use a factory harness from a...umm...wrecked Corvette or new Camaro, th
  • GMPP LS3 Crate Engine
    The LS3 uses a drive-by-wire throttle body, so there is no cable. The solution is an electronic accelerator pedal assembly that plugs into the harness and does the job.
    GMPP LS3 Crate Engine
    The LS3 uses a drive-by-wire throttle body, so there is no cable. The solution is an elect
  • GMPP LS3 Crate Engine
    The controller kit takes care of the coil-near-plug ignition system and the timing curve. If you choose to use a carburetor, there is a separate controller from MSD that is also available with a GM part number to run the coils. All the LS3 variants use the 58X reluctor wheel on the crank to trigger the ignition.
    GMPP LS3 Crate Engine
    The controller kit takes care of the coil-near-plug ignition system and the timing curve.
  • GMPP LS3 Crate Engine
    The oil pan used to be the big problem for LS swaps. In the past, you'd have to cut up an F-car pan to get an LS engine into your Chevy or buy an expensive aluminum aftermarket pan. Now GM offers a muscle car pan for just such a swap, but it is a production Hummer H3 pan that might be too deep for most muscle cars unless the engine is raised to move the sump.
    GMPP LS3 Crate Engine
    The oil pan used to be the big problem for LS swaps. In the past, you'd have to cut up an
  • GMPP LS3 Crate Engine
    GM is also involved in solving the accessory drive issue. In the past, you'd have to cobble something together from eBay parts. The GM offering is a Y-body front engine accessory drive (FEAD) that has proven to fit most muscle car-era Chevrolets. Because truck, F-body, and other LS-based offsets are different, this kit requires a Y-body balancer as well.
    GMPP LS3 Crate Engine
    GM is also involved in solving the accessory drive issue. In the past, you'd have to cobbl
  • GMPP LS3 Crate Engine
    The savior here is Edelbrock. It offers an LS-retrofit kit that includes the engine mount adapters, headers, and a complete exhaust system with mufflers and tailpipes for early Camaros and Chevelles. Our kit is for the '64 to '67 GM A-body.
    GMPP LS3 Crate Engine
    The savior here is Edelbrock. It offers an LS-retrofit kit that includes the engine mount
  • GMPP LS3 Crate Engine
    Since there is no distributor hole to access the oil-pump drive there is no way to pre-lube the engine before startup. Engine Quest sells this air tank with a hose and adapter so you can pressurize the engine with up to 100 psi of air pressure.
    GMPP LS3 Crate Engine
    Since there is no distributor hole to access the oil-pump drive there is no way to pre-lub

Head Flow
We've tested the L92 port before on a different flow bench and our published numbers are slightly higher than the ones provided by GM below. The GM tests were performed with a 4.065-inch bore plate.

Valve Lift Intake LS3 Exhaust (L92) Intake CNC Exhaust LS3
0.200 151 111 150 105
0.300 208 152 222 140
0.400 256 174 260 168
0.500 294 183 298 190
0.600 316 189 332 201
Engine Size Bore Stroke Block Type
LS1/LS6 346(5.7L) 3.90 3.62 aluminum
LQ4/LQ9 364(6.0L) 4.00 3.62 iron
LS2/LS3 376(6.2L) 4.06 3.62 aluminum
LS7 427(7.0L) 4.125 4.00 aluminum
LS3 Cam Specs
Camshaft Duration AT 0.050 Lift (Inches) Lobe-Separation Angle (LSA)
LS3, intake 204 0.551 117
PN 12603844, exhaust 211 0.522  
GMPP Hot cam, intake 218 0.525 112
PN 88958733, exhaust 227 0.525  
Parts And Prices
Part PN Source Price
Engine preluber PL40 Engine Quest $35.00
GM LS3 6.2L 19201992 GMPD $6,446.96
GM muscle car oil pan kit 19212593 GMPD $125.80
GM harmonic balancer 12620556 GMPD $103.19
GM Y-body FEAD 19155067 Scoggin-Dickey $825.85
GM LS3 controller kit 19201861 GMPD $1,506.39
Edelbrock LS retrofit kit 6758 Summit Racing $879.84
McLeod LS flywheel 460535 Summit Racing $425.39
*GM Parts Direct

A Brief History of the Production LS Family
It all started with the LS1 in the then-stupendous '97 Corvette. The engine was like nothing we'd seen before with all the go-fast theories applied from the factory. The problem, if you could call it that, was the less-than-big 3.90-inch bore that required slightly smaller valves (2.00/1.55) than we were used to. It is a great engine, but at the time, you had to part-out a '98 Camaro or said Corvette to get your hands on a used one. In 1999, the 4.8L and 5.3L LS engines were used in GM trucks and vans, opening the door for LS-hungry parts swappers like yourself to add LS power to the old Chevelle. Since we all wanted more power, guys were sleeving and boring these engines toward the magical 4.00 mark, often with disastrous results.

In 2001, the iron LQ4/LQ9 6.0L quietly appeared in big SUVs with a 4.00-inch bore, but few seemed to recognize the potential. It wasn't until the LS2 appeared in the '05 Corvette that the combination of a 4.00-inch bore and LS1/LS6 heads was mixed for a factory 400 hp. It was a really big deal at the time. To feed fatter trucks and larger displacements, GM designed another head dubbed the L92. It used the rectangular ports you see here. By 2008, big trucks like the Escalade and Yukon Denali and Corvettes were all using an even larger version of the LS called the L92/LS3. It has a 4.065-inch bore and the L92 port designs, giving it great factory numbers like 436 hp and 428 lb-ft in the '08 Corvette. There are also supercharged versions of this engine in the Cadillac CTS-V and 638hp ZR1 Corvette.

Since you can't have a truck out-gunning a Vette, the 7.0L LS7 appeared in 2008 with a 4.125 bore and went way over the top in the N/A 505hp Z06 Corvette. The LS7 is currently state of the art with a 4.125-inch bore and special LS7 12-degree heads that flow more than 350 cfm at 0.700 valve lift. We haven't seen a supercharged version of the LS7 yet but can imagine its potential. Is an 800hp Corvette in the future?

Would you like meatballs with that?

Once again, do not hook this up to your barbecue.

SOURCES
Edelbrock
2700 California St.
Torrance
CA  90503
310-781-2222
www.edelbrock.com
McLeod Industries
1600 Sierra Madre Circle
Pasadena
CA  92870
714-630-2764
www.mcleodind.com
EngineQuest
2580 N. Commerce St
North Las Vegas
NV  89030
800-416-8628
www.aaeq.net
GM Parts Direct
Greensboro
NC
800-316-8634
www.gmpartsdirect.com
GM Performance Parts
P.O. Box 33170
Detroit
MI  48232
800-577-6888
www.gmperformanceparts.com
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