A close-up of our bobweight card. Gressman centered each bobweight using an aluminum spacer. This ensures that each bobweight will be located in the exact center of each rod pin. Gressman spun our crank on his pro-ball balancer. Our Lunati crank is a high-quality, forged, non-twist steel unit featuring a 4.000″ stroke. As you would [...]
All main studs are installed finger-tight, with just an added scooch to make sure they’re seated. The main caps slid on easily, with no stud splaying interference. Be careful when installing the main caps. Each cap is numbered for location, as is the block. Be sure to install caps with cap numbers on the same [...]
LS PROJECT, PART 2 BLOCK PREP AND BALANCING by Mike Mavrigian all photos by author We swapped out the OE torque-plus-angle main cap bolts for a set of ARP studs. This will provide added strength and will eliminate wear on the block’s female threads during future servicing. I recently visited Gressman Powersports where Scott Gressman [...]
While measuring our lifter bore diameters, they seem a bit on the tight side, so we’ll likely hone to size, but will wait until we have our lifters in hand to accurately determine lifter oil clearance. The LS blocks feature lifter bore locations that are recessed in these deep pocket areas. The OE plastic lifter [...]
Our block arrived with OE powder metal pain caps and installed cam bearings. Our bores’ center distance measured 4.400″, which met the OE spec. This blueprint drawing shows cam-to-crank centerline as 124.08mm (4.885″) and deck height (crank centerline to deck) as 234.7mm (9.240″). The rear of the block features already-drilled and tapped bellhousing bolt holes [...]
PROJECT LS2, PART 1 We examine the block. by Mike Mavrigian all photos by author Our new LS2 aluminum bare block was purchased from Scoggin-Dickey Parts Center. It arrived via UPS in a wood crate. THE BLOCK We’re starting this project build using a new LS2 aluminum block purchased from Scoggin-Dickey Parts Center. The LS2 [...]
LS1 chamber. LS1 intake ports. All except L92 and LS7 feature cathedral style intake ports. Cathedral intake ports measure approximately 3 1/8″ in height. Cathedral intake ports measure approximately 1″ in width. Exhaust ports are D-shaped. The LS6 heads feature a casting number of 243. A view of LS6 intake ports. Heads feature pushrod clearance [...]
In addition to four vertical main cap bolts, each main cap also features one side-entry bolt per side. The Gen III and Gen IV blocks feature the thrust bearing located at the No. 3 main. The center valley on this LS6 block features two knock sensor bung locations. The LS7 blocks feature an easy-to-find cast-in [...]
CAMSHAFTS All LS series camshafts are of the roller style. The LS series of engines utilize a camshaft timing sensor. To provide a signal to the sensor, 1997-2004 LS engines feature a machined reluctor on the camshaft, located immediately in front of the No. 5 main cam journal. Camshafts from 2005 and later eliminate this [...]
LS ENGINE TECH The current new generations of GM engines are here to stay and represent the hot ticket for today’s and tomorrow’s hot-dog smallblocks for both street performance and racing applications. It’s time to get up to speed. by Mike Mavrigian photos by author LS6 aluminum 5.7L block. LS2 aluminum 6.0L block. The Gen [...]
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