Custom Crankshafts and Connecting Rods
As an engine builder, you get to decide what parts go into the engines you build. If you’re rebuilding a stock engine to stock specifications, you’re probably going to use a reconditioned stock crankshaft and connecting rods to keep costs down. There’s no reason to upgrade these parts because they should be adequate for the
HPBG: Choosing Aftermarket Cylinder Heads
If the performance business is about one thing – it’s about improving upon what comes in the door and making it better for your customer’s application, whether he’s racing down the quarter mile, hitting the twists and turns of a natural road course, or just driving it to the movie theater with his girl by
Racing Rocker Arm Technology
The rocker arms play a more important role than ever these days in high performance valvetrains. The rockers are the teeter-totters that translate the upward motion of the lifters and pushrods to the downward motion that opens the valves. It seems like a relatively simple task, but it demands the utmost from the design of
Breakin-In Is Hard To Do
Before we begin discussing assembly lubes and break-in oils, I would like to emphasize that no one factor is responsible for racing success (or failure). It’s like an algebraic equation with a lot of variables, all of which must be addressed. The same is true of engine assembly and break-in. You must utilize only those
Crack Detection and Correction
First off, let’s get one thing perfectly clear – there’s no such thing as “flawless.” Like those shocking tabloid photos of that Hollywood actress who gets blindsided beside a bistro, even the most conscientious engine builder sometimes has to deal with surprising surface imperfections. And just as she has paparazzi to expose the damage and
Takin
Back in the old days, the late ’90s, when the economy was strong and incomes were high, people had a lot more money to put toward their favorite hobby, which for many was a souped up car that could be driven on the street but maybe also a little on the track as well. Today,
7 Shop Survival Tips
Ford 5.0L/302 "Cobra" Cams Problem: Ford made a limited number of the Mustang Cobras with a "super-high-output" 5.0L in ’93, ’94 and ’95. They all had a unique roller cam (p/n F3ZZ-6250-A) that can be identified by the "GT" stamped on the barrel, right behind the distributor gear (see Figure 1, at right). This cam
Performance Icon Carroll Shelby Dies at 89
In the 1960s, Shelby raised the profile of American racing machines on the international sports-car circuit by packing powerful Ford V-8 engines into lightweight British roadsters, and by developing racing cars for Ford. His Shelby Cobras proved worthy competitors to the likes of Ferrari, Maserati and Jaguar and became prized collector’s items – today they
Choosing Valvetrain Components: Lifters, Pushrods, Springs & Rockers
The type of parts you ultimately choose will depend on the application (street performance, circle track, drag, marine, etc.) and any rules that restrict the type of camshaft, lifters or other valvetrain components that are allowed. But don’t overlook your customer’s budget. Affordability often limits your choices if a customer just doesn’t have the bucks
Late Model Performance Cylinder Heads
As the economy continues to come out of its slump, cylinder head manufacturers are seeing a growing demand for new cylinder heads that can deliver race-winning performance. Whether the heads are upgraded aftermarket heads for traditional small block/big block Chevy and Ford applications, or hot heads for the latest generation of Chevy LS and
HPBG: Racing Piston Technology
Munro had a problem with melting his cast pistons so he kept trying to develop his own out of melted down GM pistons. Today’s piston makers use a little more modern techniques, but the principle is the same: try, test and improve. On the outside, pistons tend to look the same. They are round slugs
Cracked Cylinder Head Repair
It seems as if many cylinder heads are doomed to crack from the very start because of their lightweight construction and design. Aluminum overhead cam (OHC) heads, in particular, are often found to be warped as well as cracked. But so too are many pushrod cast iron heads. Cracks are often blamed as the cause
Hydraulic Camshafts and Lifters 101
Closing up the gap between the tip of the rocker arm and the top of the valve stem reduces the pounding effect that can accelerate valve and rocker wear. Because of this, most of the push rod engines that have been built for the last 60 years have come factory-equipped with hydraulic camshafts and lifters.
Cam Drives and Timing Components
Cam timing plays a huge role in an engine’s power curve. Advancing cam timing shifts the power curve more toward the lower rpm range, while retarding it moves the power curve higher up the rpm scale. If an engine is being built for a particular application (stock, street/strip, drag race, circle track, you-name-it), how the
Smooth Moves: Today’s Surfaces Often Demand Different Finishes
When multi-layer steel (MLS) head gaskets became commonplace a number of years ago, there was a lot of concern that aftermarket surfacing procedures might not be able to reproduce the mirror-like finish that the vehicle manufacturers said was absolutely necessary to seal MLS head gaskets. The challenge was to duplicate the factory finish using out-dated
Inside Flat Tappet Camshaft and?Lifter Technology
Roller cams have a couple of advantages over traditional flat tappet camshafts: they reduce friction, and they can be ground with more aggressive cam lobe profiles to make more power. You can also swap roller cams without having to replace the lifters. But the roller cam’s main disadvantage compared to flat tappet cams is its
Valves, Guides and Seat Materials and Selection
Ginsu knives became a household name by blasting infomercials showing how their superior steel blades could cut through a shoe and then slice a tomato paper-thin. The blades would bend and flex and never lose their sharpness. Millions of homeowners bought the knives; however, you would be hard-pressed to find an executive chef who used
Performance Lifters, Pushrods and Valve Springs
Low friction roller lifters replaced flat tappet lifters many years ago in stock production engines, but there are still plenty of hot flat tappet cams bumping the valves open in vintage muscle cars, street rods and race cars. Even NASCAR is still using flat tappet cams to actuate the valves. The advantage of flat tappet
Common Failure Modes
For years, B&G Machine had been a diesel machine shop serving Seattle and the upper Northwest part of the U.S. To address certain market conditions in the mid- to late-’90s, we began building diesel engines. In doing so, we tried to identify the engines that would best serve a captive market – markets that would
Evolving Crankshaft Designs and Applications
In the early days, a crank didn’t have to be very sophisticated or strong because most engines were an inline design, and the loads and speeds were relatively low. Fast forward to today. The evolution in engine technology, power and performance has led to a whole new generation of performance crankshafts that are a mechanical