This 427ci LS iron short block is ideal for intermediate range boost. The Dart block is a big leap over a GM block as is the Callies 8-counterweight crank (details below). Add in the Callies rods, Diamond pistons, upgraded fasteners, our precision CNC machining and you've got a dependable short block that will last. Here is what you're getting:
- Dart LS Next SHP Block - 4.125" bore
- Callies' fully counter-weighted (CCW) Apex crankshaft
- Calico coated rod and main bearings
- Callies Ultra I-Beam Enforcer connecting rods
- Diamond R-Series 2,000 hp-rated pistons
- .225 wall wrist pin
Available with either 15-degree (LS3) or 12-degree (LS7) valve reliefs.
The engine block is the foundation any build. The Dart LS Next design is both solid and user friendly. No one has been using them longer than us. Dart's late founder, Richard Maskin, personally presented us with Serial #0002. (Dart cut up #0001 for QC checks).
- Full side skirts to accommodate OE oil pans
- Accepts LS style Oil filters
- Retains all factory bolt hole locations
- Longer cylinder sleeves to keep piston fully supported
- Priority main oiling
- 4 bolt splayed main saddle for greater structural strength
Fasteners are literally what hold the engine together. We replace the main bolts with main studs for more precise and reliable clamping force. The Dart block's 6-bolt per cylinder design provides a big jump in applied clamping force over a 4-bolt design. We take this short block a big step further by machining the block to accept the included 1/2" head studs. These exert 40% higher clamping force than comparable 7/16" studs as explained in this blog. The Dart 1/2" head stud kit is included in the indicated price. Getting the fastener kit with the short block is convenient. More importantly, getting them from us assures authenticity.
The center counterweighted Callies Apex crank has a 4.000" stroke and is made from extremely clean 4340 Timken alloy. The center counterweights are a major upgrade as they increase the cranks stiffness by about 25% while reducing harmonics. The net result is less stress on the main bearings and longer engine life.
This combination of Apex crank and Ultra rods can be modified depending on end use application. Callies' more budget-friendly Compstar line is great for lighter boost. Their 100% Made in USA Magnums are their best forged crank. Popular options at the Magnum level include larger diameter lifter bores, CA-625 rods bolts and aluminum instead of steel connecting rods. Call us at 815-725-2727 for help in sorting through the various options.
Topping off the rotating assembly are Diamond's Race Series pistons which are machined with their newest and most precise CNCs in Clinton Michigan. Among their features :
- 3D milling on piston crowns for ready to install finish
- Valve pockets designed to work with most aftermarket cylinder heads
- Offset pins for quiet operation
- Moly skirt coating for friction loss and skirt wear protection
- Side gas ports for better ring seal
- 2618 material for High HP-NOS-Boost applications
- You can select either the LS3 or LS7 piston design. Dish-type is standard but there are a wide range of options.
Calico-coated Clevite bearings are standard. The windage tray we make for these blocks is an available add-on.
The machining of your short block is as important as the parts selection. BOROWSKI RACE ENGINES, INC. boasts state-of-the-art CNC machining equipment which empowers our staff to build the best engines available. Primary machining is done on our Rottler 4-axis CNC mill and CNC diamond hone. Together, these provide the most precise achievable dimensions and surface finish yielding in turn, the best performance and longevity.
Last but not least, the skill of the people who finish-machine and assemble your short block is just as important as the parts, machining and design. We've got some of the best around and we have spent a lot of time and money on their training. This investment in our people was recognized by the State of Illinois with their Business Leadership award. We have also been recognized by Engine Builder Magazine as Race Engine Builder of the Year.
Click BUY IT NOW to get to our website for more information or to place your order. Questions? Please call us at 815-725-2727.
Notes:
1. This short block is not intended for pollution-controlled applications and may not be legal for transportation use.
Built by people who love motorsports for people who love motorsports
