If you have been keeping up with the Horsepower Monster’s 427 Small Block Buildup, we’ve wrapped up the final video in the series with a dyno session–you can find it above. But if you are new to the build, we recommend staring from the beginning–all the videos in the series are posted below.
These days it’s getting pretty hard to do anything new with the classic small block Chevrolet engine. Heck, even big inch strokers have been done before.
But we promise, this is different. Before, getting over 400 inches into a small block meant weeks of tedious grinding and prefitting along with expensive custom components. The process was so time consuming and expensive it made building a Chevy bigger than the classic 383 inches more trouble than it was worth. But now, with intelligent component selection from the right manufacturers, you can build a 427 with all off-the-shelf components. And we’re going to show you how.
Not only is this engine package easy to build, but by using all readily available components it makes building this attention-grabbing stroker basically the same cost as a well appointed 350. The key is Dart’s outstanding SHP Chevy block and a set of innovative connecting rods from Callies. A new SHP block is barely more expensive than a stock block pulled out of a junkyard and machined back to spec–plus it’s capable of handling much more horsepower and can handle 3.750 inches of stroke and 4.125 inch cylinder bores without breaking a sweat. Normally, using a crank with more than 3.75 inches of stroke in a Chevy small block with a standard cam tunnel location will send the sides of the rods crashing into the cam lobes–and we all know that’s not good. But the Ultra XD I-beam rods have the fasteners on the big end of the rod offset so that the side closest to the cam lobe is moved down, creating 0.050 of an inch of extra clearance. We also ordered up a reduced base circle cam from Comp Cams to be extra safe, but the Callies rod is enough to fit an impressive four inches of stroke without having to grind the rod caps.
Our goal is to build an engine capable of 550 horsepower or more than will be happy on pump gas and can be driven every day. This is not a tempermental, high-compression race motor that’s poorly suited for street use–this is a street motor that’s should make great power, generate loads of torque and have a rumble that will turn heads. Plus, it should be strong enough to handle a strong dose of nitrous or whatever else we choose to throw at it in the future.
The first video in the series (above) features the work required to balance the rotating assembly as well as clearance both the K1 Technologies crankshaft and the Dart SHP block. Thankfully, the clearancing work required is minimal and after this the engine should practically fall into place.
This time around we’re actually putting stuff together. In particular, rods, pistons and the crankshaft. Plus, we take a look at a new system from a company called KRAMM-Lox that makes installing piston pin locks a snap–literally.
We worked very closely with Comp Cams to choose the perfect cam for this build. Just like everyone, we want to make great power but don’t want to give up any driveability. We also install the timing set, ATI damper and Edelbrock aluminum water pump.
Finally, with Part Four we are starting to wrap things up. After much deliberation, we settled on a pair of Dragonslayer aluminum cylinder heads from Brodix, and now that we’ve seen them in person cannot wait to see how they perform on the dyno. We also wrapped up the valvetrain with a set of hydraulic roller lifters and a really trick Ultra Pro Magnum rocker arms–both from Comp Cams. For the ignition, we chose a comprehensive setup from Pertronix, which includes the distributor, coil, and plug wires.
At first glance, the intake manifold may look a little odd. That’s because we’ve already had the Weiand Sealth dual plane intake treated to a couple coats of clear coat. The idea is to seal off the aluminum so that dirt and grime won’t grunge it up so quickly. Otherwise, the Weiand piece is as it came right out of the box. It is one of the most aggressive dual-plane intakes we could find and should do a good job of feeding all 427 cubic inches with all the air and fuel they can handle. Finally, topping everything off is one of Holley’s new Ultra HP carbs with all the bells and whistles.
Finally, we get down to the brass tacks–the dyno session. You don’t want to read any more, go ahead and check out the video:
In case you want to stare at it some more, here’s that dyno sheet once again:
And finally, if you want to try this build yourself, here’s the printable parts list. Make sure to let us know what you think in the comments below.