LSA vs. LM7 This shot illustrates the four distinct cam sprockets offered in the various LS motors, including the standard three-bolt (top left), the three-bolt 1X (bottom left), the three-bolt 4X (bottom right), and the single-bolt 4X (top right). In reality, the Holley Dominator EFI system allowed us to test the cams without the need for a cam sensor. This shot illustrates the four distinct cam sprockets offered in the various LS motors, in Designed for the supercharged Cadillac CTS-V and Camaro ZL-1, the LSA cam offered plenty of power on the normally aspirated 5.3L. The peak numbers jumped from 353 hp and 384 lb-ft to 389 hp and 394 lb-ft. The mild intake duration of just 198 degrees limited power production higher in the rev range, but the extra exhaust duration allowed the power to carry much better than the LM7. The 33hp difference between the LSA and LS9 cams is a clear indication as to why the LS9 cam is such an attractive upgrade for ZL-1 and CTS-V owners. Engine Designation: LSA Displacement 6.2L Lift 0.480/0.480 Duration 198/216 degrees LSA 122.5 degrees Idle vacuum 21.8 in-Hg Cranking compression 184 psi Peak power 389 at 5,600 rpm Peak torque 394 at 4,800 rpm Average HP 300 Average TQ 365 HP/TQ gains (over LM7 cam) at 2,500 -27 lb-ft 3,500 -3 lb-ft 4,500 +8 lb-ft 5,500 +37 lb-ft (38 hp) 6,500 +54 lb-ft (68 hp) Crane Cam Trio vs. LM7 To finish up the Ultimate LS cam test, we decided to test a trio of LS grinds offered by Crane Cams. The cams range from a mild Direct-Fit cam, designed to drop right into a 5.3L truck or other LS application without need to swap springs, to a healthy (but still streetable) performance grind that offered up 130 hp over the factory LM7. The first cam from Crane offered 0.502-inch lift, 200 degrees of duration, and a 113-degree LSA. This Direct-Fit cam offered substantial torque gains, besting all of the factory offerings for peak torque production—impressive given the mild specs (smaller than most of the factory offerings). The Direct-Fit line is perfect for LS owners looking to swap cams without the need to change springs. Cam number two sported 0.551 lift, a 210/218 duration split and 116-degree LSA (think LS6 with slightly more intake duration). This cam offered 411 hp and 406 lb-ft of torque, bettering the LM7 from 2,800 rpm through 6,500 rpm while besting the LS2, LS3 and LS6 grinds. The final cam was the high-horsepower and torque champ of the test, with 0.590 lift, a 224/232 duration split and 115-degree LSA. This cam shared the exhaust specs with the LS7 and LS9 and lift specs with the LS7 (with 1.8 rockers). The 224 cam from Crane increased the power output of the 5.3L to an impressive 442 hp and 412 lb-ft of torque while offering less of a trade off in low-speed torque than the LS6, LS7, or LS9 grinds. In fact, the 224 cam was consistently up by 25 lb-ft over the LS7 and LS9 cams and equaled or bettered the LM7 cam from 2,900 rpm to 6,500 rpm. Crane Cam Trio: 200, 210, 224 Engine Designation: LS Crane Came Trio 200 210 224 Displacement 4.8L–6.2L Lift 0.502/0.502 0.551 0.590 Duration 200/200 degrees 210/218 degrees 224/232 degrees LSA 113 degrees 116 degrees 115 degrees Idle vacuum 22.6 in-Hg 20.3 in-Hg 17.8 in-Hg Cranking compression 188 psi 182 psi 176 psi Peak power 380 at 5,400 rpm 411 at 6,000 rpm 442 at 6,200 rpm Peak torque 401 at 4,700 rpm 406 at 4,700 rpm 412 at 5,000 rpm Average HP 302 311 315 Average TQ 371 378 380 TQ gains (over LM7 cam) at 2,500 0 lb-ft -10 lb-ft -25 lb-ft 3,500 +14 lb-ft -9 lb-ft -8 lb-ft 4,500 +15 lb-ft +15 lb-ft +16 lb-ft 5,500 +29 lb-ft (30 hp) +55 lb-ft (57 hp) +69 lb-ft (72 hp) 6,500 +32 lb-ft (40 hp) +80 lb-ft (99 hp) +105 lb-ft (130 hp) SOURCES Aeromotive 7805 Barton Street Lenexa KS 66214 913-647-7300 www.aeromotiveinc.com Gandrud Chevrolet 800-242-2844 www.GandrudChevrolet.com FAST 3400 Democrat Road Memphis TN 38118 877-334-8355 www.fuelairspark.com « | 1 | 2 | 3 | View Full Article By Richard Holdener Enjoyed this Post? Subscribe to our RSS Feed, or use your favorite social media to recommend us to friends and colleagues!