Found this on another E site, wondering if anyone has tried or thought of an RSX head swap yet, seems like there may be a risk of an E engine self destructing...
RSX (K20A2) Head Swap: Ref. April/May Honda Tuning, K series engine family, including the CR-V's K24A1 and the RSX Type S's K20A2.
CRV Excerpt: Following the logic of Honda's engine codes, the K24A1 is a 2.4-liter version of the K series. Following a philosophy similar to the B20 found in the previous CR-V, it's tuned to be a torque monster with a long, 99 mm stroke. That's a full 13 mm (0.51-in.) longer than any of the K20 engines. The extreme stroke works. With 162 lb-ft available at a low 3600 rpm, the CR-V is a veritable stump puller among small four-cylinder SUVs.....
...Frankenstein Returns?
The K24A is more closely related to the K20A3 and K20A. While it uses the same i-VTEC tuning as those engines, it's the long stroke design that's intriguing. The difference is in the block. The K24's deck height is roughly 19 mm higher than its smaller siblings. It's also slightly bored, with 1 mm larger cylinders. The compression ratio is also down slightly from the non-Type S engines, 9.6:1 vs. 9.8:1. So what? Well, the natural temptation is to throw the K20A2's efficient head onto the K24A1 block, raise the redline and have a torquey, ultra-powerful i-VTEC stroker Frankenstein monster engine.
The actual bolting on part wouldn't be too difficult, as the heads should mount right up. However, you do run into an issue with piston speed. At its 7900-rpm redline, the K20A2 in the Type S has a piston speed of 4464 feet per minute (fpm). Thanks to its long stroke, the K24A1 comes close to that, running at 4225 fpm at its much lower redline of 6500 rpm. By the time you've spun your K24 up to just 6900 rpm, you're already at 4485 fpm, and at the 7900 rpm redline of the K20A2, you're at a crazy 5135 fpm. For comparison, even the hyperkinetic S2000 with its 9000 rpm redline doesn't exceed 5000 fpm (it maxes out at 4965 fpm). And the Integra's B18C1 only reached 4573 fpm. Translation: If you're going to plunk a K20A2 head on a K24A1 block and redline the concoction to 7900 rpm without seriously building up the bottom end...duck.
There's also some good pics of the CR-V's engine block and a nice comparo chart of the various K series engines, as well as the S2000 and Integra GS-R. One thing I noticed was that the CR-V shares the same 87.0 mm bore as the S2000, while the other K series engines all have an 86.0 mm bore. Hmmm...
RSX (K20A2) Head Swap: Ref. April/May Honda Tuning, K series engine family, including the CR-V's K24A1 and the RSX Type S's K20A2.
CRV Excerpt: Following the logic of Honda's engine codes, the K24A1 is a 2.4-liter version of the K series. Following a philosophy similar to the B20 found in the previous CR-V, it's tuned to be a torque monster with a long, 99 mm stroke. That's a full 13 mm (0.51-in.) longer than any of the K20 engines. The extreme stroke works. With 162 lb-ft available at a low 3600 rpm, the CR-V is a veritable stump puller among small four-cylinder SUVs.....
...Frankenstein Returns?
The K24A is more closely related to the K20A3 and K20A. While it uses the same i-VTEC tuning as those engines, it's the long stroke design that's intriguing. The difference is in the block. The K24's deck height is roughly 19 mm higher than its smaller siblings. It's also slightly bored, with 1 mm larger cylinders. The compression ratio is also down slightly from the non-Type S engines, 9.6:1 vs. 9.8:1. So what? Well, the natural temptation is to throw the K20A2's efficient head onto the K24A1 block, raise the redline and have a torquey, ultra-powerful i-VTEC stroker Frankenstein monster engine.
The actual bolting on part wouldn't be too difficult, as the heads should mount right up. However, you do run into an issue with piston speed. At its 7900-rpm redline, the K20A2 in the Type S has a piston speed of 4464 feet per minute (fpm). Thanks to its long stroke, the K24A1 comes close to that, running at 4225 fpm at its much lower redline of 6500 rpm. By the time you've spun your K24 up to just 6900 rpm, you're already at 4485 fpm, and at the 7900 rpm redline of the K20A2, you're at a crazy 5135 fpm. For comparison, even the hyperkinetic S2000 with its 9000 rpm redline doesn't exceed 5000 fpm (it maxes out at 4965 fpm). And the Integra's B18C1 only reached 4573 fpm. Translation: If you're going to plunk a K20A2 head on a K24A1 block and redline the concoction to 7900 rpm without seriously building up the bottom end...duck.
There's also some good pics of the CR-V's engine block and a nice comparo chart of the various K series engines, as well as the S2000 and Integra GS-R. One thing I noticed was that the CR-V shares the same 87.0 mm bore as the S2000, while the other K series engines all have an 86.0 mm bore. Hmmm...
