The Type R pistons have a black dry film lubricant coating on the skirts for longer wear and less friction as well as additional oil holes in the ring grooves for better high rpm oil control. Type R pistons also have holes in the wrist pin bosses to improve wrist pin oiling. As an interesting and useful fact, all of the B- series engines have the same compression height, so the pistons interchange.

For a Honda street engine that will run on pump gas, the maximum compression that should be run is in the low 11:1 range. The reason why Hondas can get away with this high compression ratio with modern
unleaded fuel is mostly because of their superior combustion chamber shape and small bore diameters. Higher compression than this requires racing gas to avoid detonation. With cast pistons detonation should be avoided at all costs as they are more brittle than forged pistons.

The Integra Type R piston is available in two versions, the P73-00 JDM version and the P73-A0 U.S. market version. The difference between the two is that the JDM piston has a slightly taller dome, which gives about 0.2 higher compression. The U.S. Type R A0 piston is the piston to use in the larger
displacement LS Frank engine, as it will yield approximately 11:1 compression with this combo due to its lower dome. The JDM 00 piston is the piston of choice for a B18C as it will yield about 11:1 in this combo.

The JDM Civic Type R or PCT piston has the highest dome of all the Type R pistons to get 11:1 compression out of the smaller B16 engine. It's not recommended this piston be installed in a B18C or a B18B or a Frank engine as the compression ratio will end up being unstreetable, close to 12:1. This
compression is good for mild race applications with racing fuel, and is in fact a popular combo for hybrid Civics raced in NASA's PTTC road racing class.

When running Type R pistons on a B16A or a B17A engine, you must remove 1mm of material on each side of the small end of the connecting rod in order to have sufficient clearance where the rod meets the piston. Any automotive machine shop can easily do this operation.

The Integra Type R throttle body is 62mm up from the stock 60mm B18C throttle body.The JDM Civic Type R B16A part is a good manifold; it has short runners, good for high rpm power and a larger plenum chamber. It is close to identical to the U.S. Integra Type R intake manifold.

The JDM ITR header works on the B16A and B18C engines; it has a slick 4-1 layout, which is good for top-end power over the stock tri-y manifolds. The JDM manifold features quality 100 percent stainless construction. Note the trick staggered collector for better ground clearance. It's hard to believe this is a stock piece. The manifold also has brackets for adding the stock heatshields if you want to go stealth.

Here is a shot of the bottom of the JDM CTR manifold; notice the short, straight runners.

Here is the JDM ITR Manifold mounted on an engine. As a warning, since 11:1 is close to the limit of streetable pump gas compression and the fact these pistons have relatively high domes, it's important to verify your engine's compression ratio, valve-to-piston and piston-to-head clearance if your head was modified by milling or quench welding before final assembly. The head and piston domes should be cc'ed and the clearances checked by the clay method to insure that no interference will occur.

Intake and Exhaust Manifolds
A popular swap to gain some additional power is to run an Integra Type R manifold. The Type R manifold is a short, larger diameter, single stage manifold with a larger plenum. It lacks the dual-stage runner system of the B18C engine, and is optimized for top-end power. When doing a manifold swap, you can use either a U.S. Integra Type R or JDM Civic Type R manifold; both work equally well. The only difference is the location of one vacuum fitting on the manifold's plenum, which has absolutely no effect on anything.

The Type R manifold is good for about 6 hp at the wheels at high rpm, with perhaps a slight loss in power below 5000 rpm. The manifold is a direct bolt on the B16A cylinder head and thus works well for any B16A or any Frank engine using this head. It also fits on the rare B17A1 '92-'93 Integra GS-R engine. On
the B18C, the flange of the manifold must be extensively modified for it to fit, as only the bottom manifold-to-head bolts line up. There's also a problem with the location and alignment of the coolant passage, this must be welded up and ported for the correct shape. The upper boltholes must be welded up
and redrilled in the correct location and the head match-ported to the manifold. After welding, the manifold's head flange must be resurfaced so it will seal properly. After all of this mess, the injectors hang down into the airstream and disrupt flow, making this a poor way to do things.

Perhaps a better way is to cut the flange off of both manifolds and weld the B18C flange onto the Type R manifold. After welding, the manifold's runners can be cleaned up and match-ported for good flow. Fortunately, if this seems like a great deal of work, Skunk 2 has come up with a bolt-on copy of the Type R manifold that bolts right onto the B18C with no hassle. American aftermarket giant Edlebrock is also offering a direct bolt-on B-series manifold.

To do a clean install of a Type R manifold onto a B16A head, you need the following parts: a fuel rail from a '94 Integra; a '93 B16A del Sol; a '99 Civic Si, '92 or later JDM B16A or a B18C engine; an idle air control valve and 12mm mounting bolts from a '92 and later Integra, a '92 and later Civic Si or EX or a '97- '98 CRV; a throttle body gasket from an Integra Type R; and an intake manifold gasket from an Integra Type R.

A 62mm Type R throttle body to replace the stock 60mm one is a nice addition at this point, but it may be cheaper to get an aftermarket 64mm throttle body from RC engineering or JG.

On the exhaust side, a very effective upgrade is to install the JDM Integra Type R exhaust manifold. This is good for about six more wheel hp over the stock manifold. Interestingly enough the JDM manifold is a 4-1, equal length, tubular stainless steel header. The JDM Type R exhaust manifold fits all B-series engines.

The JDM Civic Type R rod features a stronger steel with more chromium in it. This is sort of like chrome-moly, the well-known high-strength U.S.-spec steel. In this picture, you can see the stout forged construction, beefy rod bolts and spot faced rod bolt bosses, all features that add strength.
Connecting Rods The JDM Civic Type R with the B16A engine has improved connecting rods featuring steel with higher chromium content. Adding chromium to the steel greatly increases its strength, much like the chromium
and molybdenum in chromoly makes it much stronger than regular steel. This steel is standard in the U.S. B18C and Integra Type R rods, but not in the U.S. B16A. The B16A still has pretty decent rods, so it's probably not worth it to go out and buy a set of JDM rods, but if you do have a choice, it's good to know the JDM B16A rods are stronger.

Any stock rod can benefit from polishing the beams and shotpeening. These operations can improve the rods fatigue strength by more than 100-percent.

It's impressive that with a well thought out combination of factory parts, good assembly and some headwork, a Honda engine can obtain very respectable horsepower and torque figures while still keeping factory-like reliability and loan-to-your-grandma driveabilty. There are not too many engine families on
earth that can make this claim from any manufacturer. With Hondas, cheap and reliable power is just a call to a JDM engine importer or a dealer away.