Now I realize I've been slacking on the atricles lately.... So here's a small tidbit.

-Jeff

Honda B-Series Stroker Engine Shootout Part 1
Examining The Deck Plate, Long Rod And Stock Deck, Short Rod Approaches To Big Displacement Honda Power Presented By JE Pistons, Crower, Benson's and BCE Racing Heads

By Staff

One might find a naturally aspirated engine build-up story in a magazine labeled Turbo & High-Tech Performance odd, but in an industry dominated by the Honda market it's our duty to illustrate the high-tech side of naturally
aspirated Honda performance.



In a recent Honda build-up story, we explored the advantages of adding deck space to increase the rod length in a B-Series engine. While this seems to be the latest craze in all-motor performance, a question came up in a conversation--is a deck-plate necessary? What does it take to make power? Horsepower vs. torque, high rpm vs. low-end power, long rod vs. short rod and so on and so fourth.



These interesting questions spawned even more and the outline of a story materialized. This all comes down to engine theory and an engine builder's beliefs. Before you start flooding our e-mail systems with your thoughts, remember that this is an evaluation of the differences between the two modes of thinking and where minds clash, controversy soon follows. It is not an exercise to prove or disprove any theory, just understand each in a common context on an OHC engine. It is also not a strictly Honda-only issue, as all theories discussed here are transferable to any OHC powerplant.



For some time, we have wanted to do an engine build comparison but could not figure out a way to strike the perfect chord with our readers--until now. After months of preparation, we have gone to some of the best in the import and domestic business. Managing the engine building and machining is Dan Benson of Benson Machine. Cylinder head manipulation will be handled by Bill Craddock from BCE Racing Heads, while Tony Ramos of JE Pistons and Brian Crower of Crower Cams and Equipment Inc. are handling parts development. Here is a quick background on the men behind the motors and their opinions concerning these displacement increasing methods.


A noticeable difference is deck heights between a B16A and B18A block is visible on the stock blocks but with the added 25mm on the B18 block the difference in deck height becomes even more apparent. * The added one-inch of spacing means taller sleeves are needed to compensate for the longer rod. * Not only does the B16A block have a much shorter deck height compared to other B-Series engines, this particular engine was .030 thousands shorter than the OEM height after machining.

Dan Benson is the man who revolutionized the strength of the Honda block by replacing the inferior Honda cylinder sleeves with ductile iron replacements capable of taking on boost pressures in the 30-plus psi range. His work can be seen in some of the fastest racers that include Stephan Papadakis and Lisa Kubo.



Although the micrometer is not measuring the true center-to-center of the rods it does display the length difference. The true center-to-center is a difference of .892 of an inch. The LR engine is a 6.100 rod with a rod ratio of 1.63 and the SR engine is a 5.208 rod with a 1.32 ratio.


Bill Craddock is known for his extensive knowledge of Mitsubishi and Honda cylinder head technology. Bill's list of racers is widely known and he has been involved in many high-horsepower street cars. Lanny Higa ran deep into the 10-second zone in street trim, while others were in full race trim to equal his e.t.s. We're talking full interior, with no weight reduction. John Shepherd's Eclipse turbo is another one of Bill's creations. This vehicle dominates the East Coast, laying down 9-second times on street tires. A few more big-name racers supporting BCE product are Stephan Papadakis, Shaun Carlson, Mike Simon and Len Monserrat.

Crower Cams and Equipment is another industry leader in the import market. You can guarantee that all the top racers have started with or are currently running Crower rods. Now the company is on a roll helping to develop even more import cylinder head parts.

JE Pistons has been in the trenches since the beginning of the import revolution and has been able to develop different designs to better the combustion efficiency of a Honda engine, whether the application is boosted or all natural. Just like Crower's list of racers, all the top racers are or have at one time ran JE pistons in their race engines.

The Theories

One of the biggest controversies in engine building is deciding to go with a long-rod or short-rod engine. Extending the rod will benefit those who believe in bigger stroke with more torque and low-end power.

The short-rod approach creates high-rpm engines with fast piston speeds that mainly rely on peak horsepower with the engine revved in its sweet spot most of the time. We plan to build both styles on these pages documenting the differences as we go along. In their final form, each engine will be dyno tested to illustrate the difference in how--or more, precisely, where--in the powerband each makes its impact felt.

In a stroked deck-plate application, an engine is not only stroked via crankshaft, its rod ratio is also changed by lengthening the rod's center-to-center measurement, extending the deck height as well as installing taller sleeves. On our B18A engine, we not only have an advantage of a taller deck height to begin with over the B16A, we will also add an additional 25mm to the deck. This in conjunction with a billet 95mm Crower crank gives us a rod ratio of 1.63 and a center-to-center rod length of 154.94mm. This approach theoretically results in an engine that will produce more bottom- to mid-range torque while also slowing the piston speed. The advantages of this route are more bottom-end power and more displacement with some loss on the top end and a coinciding reduction of heat caused by friction. This helps maintain durability.

With the short-rod engine, we not only start with a short-deck engine block, we modify it for a GS-R stroke, which changes the rod length to 132mm for a resulting 1.32 rod ratio. The theory behind this engine is that all the horsepower will be realized in the top-end of the powerband. This means the engine will have to always be turning high rpms to effectively propel the car down the quarter mile.

Theoretically, the advantage of this engine is that it should produce more top-end power, but will not make as much in the mid range as the long-rod engine. The disadvantage centers around torque and whether the short-rod engine will generate enough to pull the weight of the vehicle from a standstill. Considering most sanctioning bodies have a 1,600-lb minimum weight requirement, the engine should technically build enough to launch a race car. Street cars may or may not be a different story.

The Engines

When comparing the engines, there are many different variables that can have an effect on their powerbands. Keep in mind our main objective is to figure out the difference between a short-rod and a long-rod engine. This is not to determine which is better; that is decided by the type of car and the expectations of the car that the said engine is installed in.

Figuring out a cylinder head was the most difficult part of this story. Since there are also many variables involved in determining the cylinder head and valvetrain characteristics, we have decided to keep things neutral by sticking with the same specs for each engine. A GSR ported head for both will be used but eventually we will play with the cam profiles to maximize potential. The accompanying spec boxes outline the hard parts of each engine and the accompanying Round Table sheds light on the concepts and preferences of each engine. The Round Table is hosted by Turbo's Gary Castillo and features enthusiastic input from Brian Crower, Bill Craddock and Dan Benson.