Aftermarket Engine Blocks - CHP How It Works

The Top Block Manufacturers In The Industry Lend Their Expertise On Selecting The Best Casting For Your Project Car.

Stephen Kim Nov 18, 2010 0 Comment(s)
View Full Gallery

Jack McInnis: "Stock blocks are often plagued by poor oil routing. In a typical OE design, the oil feed is routed through the cam bearings first, then splits off to the mains and valvetrain. This can lead to inadequate lubrication to the critical main bearing area, especially at high rpm. The stock systems also have quite a bit of restriction due to the way they are machined. High-volume oil pumps are commonly used to try and compensate for these restrictive oil passages. We relocate the main oil gallery alongside the cam tunnel so that the oil can be fed directly to the main bearings first. We also eliminate a lot of the restrictions so that oil flow is improved enough to where a high-volume oil pump is not required. Dart race blocks are machined to simplify installation of dry-sump oiling systems as well."

Jason Neugent: "Production blocks were designed based on the oiling demands of engines producing far less power than a typical performance engine. In many instances, the oiling system is simply antiquated, and routes oil to the cam bearings first instead of the mains. On the other hand, Brodix blocks have priority main oiling systems. This means that the oil will travel from the oil pump to the mains, then to the camshaft, and then finally to the lifter bores. This will ensure proper oiling for the mains, not rob the top end of oil, and still produce very good oil pressure. We have also enlarged some of the oil journals in our blocks from 1/4 to 5/16-inch for improved flow."

Rocko Parker: "The oiling system on the LSX block is different than GM's production LS-based engines. It has an additional oil feed drilled directly to the crank main bearing. This allows engine builders to reduce the feed to the lifters and use more of the oil to lubricate the crank and rods. This is something that we do not do with a production LS block because they use hydraulic lifters. The typical racer that buys an LSX block will probably opt for mechanical lifters. Likewise, the oil feed hole from the oil pump to the oil filter has been moved outboard from the centerline of the block. This allows for a larger crank throw by machining rod clearance into the block without contacting the feed supply to the filter."

LSX Block Design
Rocko Parker: "The LSX block design does not include any additional reinforcement ribs for structural support compared to a production block. The reason for this is that the production LS design underwent extensive analysis and testing to develop its strength and rigidity. The production LS7 has many improvements from past engines such as a deep-skirt block with six-bolt mains, and 10 additional head-to-block fasteners to stiffen the top of the block. These improvements have been maintained within the LSX block, which makes it a more solid combination to prior GM small-block designs. Furthermore, the LSX block design uses the architecture of the LS7 block, so the majority of the weight difference is attributable to its heavy-duty iron construction. The LSX block weighs 125 pounds more than the production LS7 block, and we have removed items like the lugs that the production machining process uses to transfer the block from station to station. Also, most of the gusset ribs have been removed, as they are not required due to the additional strength of cast iron. We assume all of our customers want eight cylinders firing all the time, so the bosses for the cylinder deactivation manifold have been removed as well."


Connect With Us

Get Latest News and Articles. Newsletter Sign Up

subscribe to the magazine

get digital get print