D’GARAGE CRX: Honda Twin-cam Swap

USDM Honda B-Series VTEC Swap Options

Honda only offered a few variants of the B-Series DOCH VTEC engine in America. To complicate things further, the 92-93 Integra GS-R was the only USDM B-Series VTEC vehicle that came with a cable-actuated transmission for compatibility with the 89-91 Civic/CR-X. Although we highly recommend OBD1 swaps over OBD2 for simplicity’s sake, we’ve gone ahead and listed the OBD2 engines as well.

92-93 Integra GS-R 94-01 Integra GS-R 97-01 Integra Type R 94-97 Del Sol VTEC 99-00 Civic Si
ENGINE CODE: B17A1 B18C1 B18C5 B16A3 (94-95)
B16A2 (96-97)
B16A2
OBD: OBD1 OBD1 (94-95), OBD2 (96-01) OBD2 OBD1 (94-95), OBD2 (96-97) OBD2
DISPLACEMENT: 1,678 cc 1,797 cc 1,797 cc 1,595 cc 1,595 cc
BORE/STROKE: 81.0 x 81.4mm 81.0 x 87.2mm 81.0 x 87.2mm 81.0 x 77.4mm 81.0 x 77.4mm
COMPRESSION: 9.7:1 10.0:1 10.6:1 10.4:1 10.4:1
HORSEPOWER: 166HP @ 7,600 RPM 170 HP @ 7,600 RPM 195 HP @ 8,000 RPM 160 HP @ 7,600 RPM 160 HP @ 7,600 RPM
TORQUE: 117 LB-FT @ 7,000 RPM 128 LB-FT @ 6,200 RPM 130 LB-FT @ 7,500 RPM 118 LB-FT @ 7,500 (94-95), 111 LB-FT @ 7,000 (96-97) 111 LB-FT @ 7,000 RPM
REDLINE: 8,000 RPM 8,000 RPM 8,400 RPM 8,000 RPM (94-95), 8,200 RPM (96-97) 8,000 RPM
ECU: USDM P61 USDM P72 USDM P73 USDM P30 USDM P2T
TRANSMISSION: Cable Hydraulic Hydraulic Hydraulic Hydraulic

B17A1: The B17A1 out of the 92-93 Acura Integra GS-R is one of the rarest engines to find due to its low production (estimated 5,000 total units). While this may be a “GS-R” engine, it is actually more similar to the B16A2/3 than the B18C1. The B17A1 is a “stroked” version of the B16 and uses shorter rods and a different crankshaft for increased displacement. Cylinder head (PR3) is also shared between the B17A1 and the B16A2/3.

B18C1: Many consider the B18C1 to be the best B-Series for high-horsepower applications. Most notable is the two-stage intake manifold that provides increased low-end torque. The 94-01 GS-R-specific P72 cylinder head also features quench pads instead of a traditional cylindrical combustion chamber of the PR3 head. The quench pads helps the swirl and combustion of the air/fuel mixture as it rises up into the chamber. Compared to the B16, the B18C1 cylinder block also features a girdle for superior strength compared to the individual mains of a B16/B17.

B18C5: The B18C5 is the absolute rarest engine to find of all five options. It was only found in the 97-01 Integra Type-R. This engine utilizes the same block as the B18C1 but features moly-coated pistons, a further balanced crankshaft and increased compression by way of domed pistons. The B18C5 utilizes a PR3 cylinder head in conjunction with upgraded valvetrain, ITR-specific camshafts, a light port job and an upgraded intake manifold with larger plenum and shortened runners. Only offered with OBD2.

B16A3: The B16A3 out of the 94-95 Del Sol VTEC is great for CARB-legal swaps since it’s an OBD1 engine. This engine is virtually the same as the B16A2 out of the 99-00 Si and 96-97 Del Sol VTECs. The cylinder head features the same PR3 unit shared with the Type-R without any of the performance enhancers. Aftermarket parts are plentiful for the B16A2/3. Due to its relatively short rod/stroke, the B16 platform is great for high-revving applications.

B16A2: The B16A2 is the most common USDM B16 as it came standard in the 99-00 Civic Si. Like the B16A3, it features a PR3 cylinder head. However, the B16A2 was only ever available in OBD2 vehicles making it a tough sell for CARB-legal swaps. If you’re going to make the jump to OBD2, a B18C1 swap would be a lot more worthwhile than a B16A2.

GEARED UP

DSPORT Magazine Honda CRX engine swapHundreds of thousands of miles can leave an engine under-powered but still going. However, it only takes a few grinds and mis-shifts to wreak havoc on a transmission. Used Honda transmissions are notorious for grinds, especially in third gear. For the 88-91 Civic/CR-X, a cable-type transmission is used from the factory and is simply the best way to go. Although some companies make an adapter kit to run a hydraulic transmission (from later models), a cable-type transmission such as the J1, S1, Y1, or YS1 is a bolt-in affair. Regardless of the transmission, it’s best to get the box opened up, inspected and rebuilt before swapping it in.

DSPORT Magazine Honda CRX engine swapWe took the YS1 over to Anaheim Gear in Anaheim, CA for a complete overhaul with new carbon-coated synchros, bearings, seals and two sliders that had endured severe abuse. With the transmission apart, we also had them swap out the factory open differential for a Quaife ATB limited-slip differential (p/n QDF1U). Simply put, an LSD outperforms an open differential in every single way. During straight line acceleration, an open differential only puts power to the wheel with less traction. An “ideal” LSD allows zero slip between the left and right drive wheels for maximum power transfer. When cornering, an open differential will tend to spin the inside tire (the tire that has less traction), causing sudden understeer. With an LSD, power is biased to the outside wheel to allow the driver to accelerate out of a turn much quicker. Whether it’s the strip, street or circuit, an LSD can greatly improve the handling characteristics of any vehicle.

NEXT EPISODE

With the engine and transmission refreshed, the next step is to join them together and find a new home for the duo. Due to the popularity of the swap, many companies offer off-the-shelf parts that cater to a B-series powered 88-91 Civic/CRX. In the next installment of Swap Shop, we’ll cover all the swap specific parts you’ll need to get that B-series bolted up to your ride.


1) D’Garage CR-X: The First Stage

2) D’Garage CR-X: Honda Twin-Cam Swap

3) D’Garage CR-X: Honda Twin-Cam Swap Part Two

4) D’Garage Honda CR-X B17A | Passing the BAR, Broken Parts, Building Up Power