A fixed 3 bladed prop has no performance potential while sailing. It's a compromise that gets the boat to move forward and backward and doesn't really do a good job at anything. A folding, feathering or self pitching prop could add as much as 1/2 knot of boat speed while sailing, depending on wind and seas. Some of them will also help while motoring, including reverse. My own personal choice is the Autoprop, but nearly every prop on the market has its own list of supporters. Note that with most props it's usually better to shift into gear while sailing to stop the prop from spinning, with the added benefit of reduced transmission wear.
A whisker / spinnaker pole to hold the genoa out is a big plus when the wind gets behind you. You can usually increase your vmg (velocity made good) sailing "wing on wing" with a poled out genoa and a preventer rigged on the boom. The preventer is a must if you want to do this in conditions above 12 to 15 knots of wind. I've poled out my 155 and asymmetrical on the same side of the boom too. Depending on the size of the headsail (135 or 155), an adjustable line control pole in the 13 to 24 or 15 to 27 foot range is a good compromise on a 400, but install a longer track on the front of the mast so you can gybe it safely. You don't want to pass a large and heavy pole end-toend while the boat is moving. Better to raise the inboard end up the track to allow it to swing through the triangle. Remember that you have to totally support and control the "free" (outer) end of the pole when in use.
Line control genoa cars are useful if you want to trim the sail safely and easily while on the current tack. The position of the car on the track controls the angle of the sheet and therefore the relative loading and shape of the sail, top to bottom. The cars that come with the boat use a spring pin to position the car and are OK while standing still or for adjusting the lazy sheet. But you can't move the car if the sheet is under any real load, unless you have a 4 tol or better purchase through a line control car. just pull the line and the car will move forward, the load on the sheet will move the car back when the line is released. Garhauer markets a ball bearing car system at a reasonable price too (at least compared to some of the others).
Tuning the standing rigging is something that many people tend to ignore. There are C400 owners out there who have never tuned their rig even after 11 years, and some new boats where wire tension was set wrong by their dealer's "professional" rigger. if the boat can sail, it's probably OK.
Not true. I've been on several that are faster on one tack than the other, or are painfully slow on both. You can do it yourself too - a rigger is not really needed. I won't go into all of the details here, but the goal on the 400 is to get the stick pointing straight up - forget about rake, it was not designed for it. Bending it a drop is a whole different story and can be useful to help flatten the main. Use the main halyard to take measurements and your eyes to sight up the mast. To get the stick plumb and straight, start with the lower wires and use a tension gauge to arrive at a reasonable starting point for each wire. Note that wire tension should be in the range of 12 to 18 percent of breaking strength, with the longer wires (uppers and stays) tighter than the shorter. Do not exceed 20 percent - you need the balance as insurance for much heavier loads while sailing. Fine tuning should be done while sailing with a 15 to 20 degree heel to guarantee a good load on the rig. The windward side should be very tight; the leeward wires will lose some tension but definitely should not be loose.
I have to at least mention sail trim. If you want the boat to move well, You've got to do it. A good set of 3 or 4 tell tales on each sail (pairs on the genoa) to read air flow is a must. Since the forward half of the head sail and the back half of the main do most of the work, that is where you want them to be. There are exceptions to the rule, but you generally want to see all of them streaming backward. Your goal for getting the boat to move is to provide maximum drive with a balanced sail plan and minimal rudder necessary to hold the course. More rudder means more drag and less speed. Note that the 400 (at least mine - wing keel, full batten main and 1SS genoa) likes to be a little over-trimmed in light air and under-trimmed when it gets heavy. When it gets really windy (say 20+ knots), you've got to de-power the rig to be able to control the boat. To some that may mean shortening sail (reefing), but you can sometimes accomplish the same thing by letting the traveler out. The big main is one of the prime causes of weather helm, so reduce its power with the traveler. By the way, your traveler should be used more when trimming the main. As far as I'm concerned, the main sheet controls the shape of the sail and the traveler usually controls its angle of attack.
Very few 400s have been set up to use other techniques for improving speed. Examples include Cunninghams and Barber-haulers. The Cunningham can help the mains shape by moving its draft forward (especially helpful on a lower performance or an older and tired sail) and it's rigged by using blocks, hooks and a line to pull a cringle sewn into the main down and forward. A Barber hauler is used to move the genoa sheet outboard when reaching in light to medium wind which will increase the size of the slot between the 2 sails. You can attach a block on the toe rail and either run the sheet through it or use it to pull the sheet outboard with a 2nd block on the sheet itself.
This is all too obvious, and a problem on many boats - a clean bottom and prop could be easily worth over a knot of boat speed. You can keep it clean by short-hauling and power washing, using a diver, or getting a set of long brushes with attachments to reach almost every inch of the bottom. It does not take that much crud on the bottom to hurt your boat speed. There are also bottom paints available that have less drag than others and could be worth a 1/4 knot or more in boat speed.
Being able to control the boat with the helm is a requirement too. The steering cables should not be too loose or too tight. Too tight will make it hard to turn the rudder, and loose will make it hard or impossible to control the boat. If you've owned or driven a 50's Buick (or similar), you know what I mean. While holding one wheel firmly, the other should be able to move around 1 to 1-1/2 inches. Keep the cables lubricated also.
Finally, weight is the killer of speed. it probably can't be helped in a cruising boat, but every pound you get out of the boat will matter. just about everyone uses his boat as a storage shed with unnecessary junk tucked into every nook and corner. Think about that when your friend in his 40 foot "other boat" passes you by.
Quick and clean engine oil changes
Changing the oil in the diesel auxiliaries is usually a messy process. For those boaters who use their boat a lot, and particularly those who travel the ICW, the oil will require changing many times in a year. If your boat is equipped with Westerbeke 42B diesel (and perhaps other models), you can speed-up the process and make is a lot cleaner at the same time.
After trying various hand-pumped vacuum containers with so-so success, I installed a "Qwik-Drain" electric pump (less than $100 at that time), mounted to the starboard side of the engine compartment (refer to the picture). The 42B has a hose plumbed into the crankcase so the pump was connected to this hose. The thread on the engine hose was not the same as the thread on the Qwik-Drain hose, but I found a double-threaded fitting in an auto parts store, that matched the two ~hreads. Now all I have to do is put the discharge hose of the pump into an empty one-gallon container (saved from the previous oil change) and push the button on top of the pump. VIOLA - within about two minutes, the crankcase is empty. I plug the discharge hose and tuck it behind an adjacent bracket holding an automatic Halon extinguisher (the red thing right above the pump), which keeps it out of the way.
Of course, the filter must also be changed, so I use a technique suggested by Larry Berlin, of the Engine City Tech Institute (Mack Boring & Parts Co.). This uses a one-liter plastic beverage bottle, cut to look like a scoop, with the cap tightly secured (refer to second picture). This is placed under the oil filter so that it is tight against the filter/oil pump interface. As the filter is unscrewed, the oil runs into the scoop. As the filter disengages from the engine, it is tilted so that most of the oil in the filter runs into the scoop. This process captures most, if not all of the oil in the filter. The scoop is then emptied into the container with the rest of the old oil. Some engines might have more space around the filter, which would allow using a two-liter bottle. In this case, the filter can be slid into the scoop and handled that way. The 42B does not have that kind of access.
Having made two round trips on the ICW, for over 4000 miles each, hence requiring changing the oil about 10 times per trip, this oil change process has saved much frustration and mess.