23 Nov 2014

The dry sump bits are on the way. For some reason, a dry sump kit doesn’t seem to save money. The least expensive way (at least for the Honda K20) turned out to be to piece together a system and while a bit more work it allowed picking the exact parts wanted instead of settling for pre-selected components.

While the 70 amp Civic alternator fits, a quick check of the power budget found that: radiator fan (20A), lights (10A), water pump (10A), fuel pump 15A*, and everything else probably around 5A, for a total of 60 amps. Granted that’s worst case – at night in stop and go traffic – but it’s a bit close for comfort on the Civic unit. The single-wire unit my brother loaned me is only rated at 60A so that won’t do either. Powermaster has larger units, but they’re expensive and sole-source. That last bit is the main concern, a failed alternator at a track day or somewhere far from home would mean coming home on a flatbed. For these reasons, a 100 amp domestic pick up truck alternator was chosen. It’s far easier to source, is a bit larger, and also about half the cost of the Powermaster unit. It’ll do but will need to be rewired.

The rivets in the engine compartment floor panel tray was removed in order to get the panel off. It makes it far easier to swap out the oil pan in-place without pulling the engine. Even then though, one of the floor diagonals was in the way and had to be removed – it’ll be welded back in and a new panel fabricated. While it seems invasive, the panel and rivets weren’t in great condition after I left a handful of rivet heads in the road after bottoming out several times. (That’s since been corrected by swapping in stiffer springs and stiffening the shocks slightly.)

At the end of the day the oil pan and oil pump were out. The only dry sump part on-hand is the front pulley, ordered early since it’s needed to determine belt routing and alternator placement. For a while there was some thought about making the dry sump pump and alternator mount to one part. However, it doesn’t save any work, material, weight, and plus it means if the alternator choice is ever changed, the entire bracket has to be reworked. Best to have a dedicated alternator bracket.

Lastly, it looks like the dry sump pump will be mounted at the left rear corner of the engine compartment. It’s easier to access there and allows a taller unit rather than placing it up front behind the radiator. I’m not too thrilled about pushing oil all the way to the front of the car then all the way back. Of course, if an oil-to-air cooler ends up being installed in front of the radiator, it’ll be doing just that. In that case the tank would be relocated up front for CG reasons.

*15 amps for the fuel pump is higher than what’s used now. However, the power budget is being set up now such that a larger pump will drop right in – one intended for ethanol 🙂