It’s an old topic but with Sean’s engine swap story elsewhere in this issue, we thought it would be a good refresher to show the main ingredients for a K- or B-series swap. While several years ago a K-series swap might have been new territory, today both swaps have been proven a thousand times over and over again. So forget worrying if it’s going to fit or be reliable. It will as long as you get the right gear and do some basic homework. If you’re new to the topic, it’s always best to consult your local Honda guru or the listed specialists below to ensure you have all the right parts to make your swap a success.
First off, the B-series isn’t as powerful and new as the K but it’s more affordable and will net you 200whp naturally-aspirated or 300+whp with a bolt-on turbo upgrade. The four-cylinder DOHC VTEC engine came in a 1.6- to 1.8-liter and was rated from 160-200hp. While offered in almost all Civics and Integras in Japan, they were a little harder to come by here in the States, only equipped in Integras and a couple different model Civics. But because the motor was available here, it’s easier to get CARB-approved. You can pick up a basic B-series nowadays for around a grand but the more attractive motors will run you a bit more like the imported JDM models.
After Honda retired the B-series, the K-series took over with cars such as the RSX, TSX, Civic Si and Accord. Still one of the best transverse naturally-aspirated four-cylinders around, it makes about 160-220hp. It’s become a very easy and proven swap, and with the addition of some basic bolt-ons, you can have a 250whp K20. Priced at a higher premium compared to the B-series, engine costs ranged up to five grand for a pristine motor—but well worth it if you have the coin.
The best and cheapest way to find a K- or B-series is by checking out the sale ads on your favorite Honda forum. Also check places like Craigslist and local junkyards, too. For JDM motors, you can hit up importers like Zerolift Autolab (zerolift.com) and JDM Engine Depot (jdmenginedepot.com). But here are some other must-have engine parts you’ll need.
DC Sports B-series 4-1 header
Vibrant B-series 4-2-1 header
Blox Racing B-series header
Skunk2 MegaPower header
Buddy Club race exhaust manifold
AEM Hybrid Intake
The next piece of the puzzle is to make sure you have all the proper drivetrain components (if it already isn’t included when you pick up the motor). But remember, you’ll need the half-shaft, shift linkage and proper axles for the swap.
Driveshaft Shop Level 5.9 K-series axle/hub kit