...from Ed Spracher in Kenai, Alaska. Ed is a very interesting guy, something of a Renaissance man. He also managed to out-talk me in our phone conversation, which may surprise some of you...
He developed the modified venturi after he became convinced that fitting a one-piece venturi to his Lycoming O-320 had worsened fuel distribution to the point that it cost him an overhaul of 3 cylinders. The new venturi is a straight replacement for the stock venturi. It is designed to cause fuel mixture swirl.
The cost of the venturi is $250. I expect to receive it in the next 2 weeks. I will then perform baseline testing, fit the new venturi and then re-test under the same conditions to assess the difference in performance. Ed made some fairly interesting claims about his performance improvements during our recent conversation, but, just as they say in the motor ads, my mileage may vary.

...but not without some rework. Jesse completed the initial fitting several weeks ago. However, I could not get down to the hangar immediately because of work pressures.
When I finally went down, I checked out the installed intercom and found that almost everything worked. Except...for the pilot PTT circuit. A small, but operationally significant issue. No PTT, no talkee to anybody.
I ran out of time to troubleshoot the issue, partly because I had left my multimeter back at the house.
While I was in Durango on a skiing trip (see here for the gory details), Jesse snuck off down to the hangar one more time to check out the issue. As usual, he did a great job of figuring out the issues (another instance of "Huerta you're a ****ing genius"). There were two separate issues:
1. the PTT wiring was incorrect (found by tracing the circuits from the PTT switch on the stick all the way back to both the intercom and the panel radio).
2. that the connector in the Molex unit at the intercom end was loose.

The Molex connector required the soldering of a new connector (and, believe me, those are tiny connectors - I realized that my eyesight wasn't what it used to be when we first examined them out of the box about 6 weeks ago).
Additionally, he wired up the rear stick PTT circuit. This intercom has separate PTT circuits for the pilot and co-pilot, unlike the previous intercom which had one circuit. With that intercom, if the pilot pressed the PTT switch, anything the co-pilot said would also be transmitted. With this intercom, the co-pilot has to press his/her own PTT switch to transmit. The PTT switch has to be detachable because the rear stick is removable in order to increase rear seat room for the taller passenger.
I was planning to visit the hangar and test everything out this weekend, but with temps tomorrow forecast to be 31 degrees and 40 on Sunday, I think I will be working in the house instead...

When I bought the Long-EZ in 2000, I was already reasonably well-prepared, having already accumulated backseat passenger time in a Vari-EZE and Long-EZ, and front right seat time in a Cozy III.
However, I still had to negotiate the initial transition to My New Plane. Here is the Shevlin-Huerta Long-EZ Transition Program (patent not applied for):

Ground School 1.5 hours
POH familiarization
weight and balance calculation
plane checklists/walkaround, preparation
Initial Familiarization 1.0 hours (back seat)
commentated takeoffs + landings
backseat flight (fast, slow, maneouvering, canard stall)
Ground handling 2.0 hours
entry/exit
taxiing/ground maneouvering
moving plane on ground, fuelling
Taxi testing 1.0 hours
slow taxi
high-speed taxi (lifting nose after cutting power)
Pattern work 1.5 hours
takeoff (yes!!!)
pattern circulation
landings/touch and goes
pattern entry/exit
local maneouvering (as for
Initial Familiarization from front)
Stretching Out 2.5 hours
takeoff
fly to other airports (2 or 3)
pattern entry/touch and goes
return to home field
The naked EZ 1.5 hours
removal of cowlings, panels
wheel pants removal
preventitive maintenance items

This all worked rather well...I think that I only gave Jesse a couple of moments. The first was during high-speed taxi testing when I lifted the nose way too high (this is the Spam Can Overcontrol Tendency). The second one was when we were on final during initial pattern work and Jesse asked "what's your speed". I thought he said "watch your speed" so I responded "OK" twice before Jesse raised his voice to the point where I finally realized what he was really asking...
The main difference that takes the most getting used to is landing. You cannot make full-stall landings in a Long-EZ, so landing is the application of a modified night landing; you set up an appropriate sink rate, bleed off speed down final and aim to touch down about 5-10 knots above canard stall speed. Oh, one thing you will learn...flaring like you're flying a Cessna usually results in an amusing nose-up drift down the runway, with no sign of an imminent touch-down, until the back seat commander suggests that a go-around might be good unless you want to land in the field next door...
I also obtained some excellent off-field maintenance training when the left
side brake failed while on a cross country flight leaving Marco Island. When I started up and went to taxi off, there was no left brake whatsoever, and I ended up performing a right 360 on the ramp back to exactly the spot the aircraft had been parked. The O-ring had failed on the brake caliper - no big deal in terms of repair effort. However, Murphy's Law was operative - this happened on a holiday weekend when the airport FBO had no crew to speak of. We ended up renting a car, driving back to Tampa and driving back to Marco Island the following day to fix the problem after retreiving the appropriate tools and supplies. The local NAPA happened to have the correct O-ring for the brake caliper and after only a few hours, we were winging our way back to Tampa, only a little the worse for the wear.
If you don't have much experience with the maintainance side of aviation, I
highly recommend you get some experience with the aircraft early on in the
process. Experimentals will malfunction and occasionally break, and certified mechanics will sometimes not be helpful due to liability and other concerns.

My engine has the "stock" Marvel-Schebler MA-4SPA carburetor. This is a replacement unit installed 2 years ago once the original carb was found to have been beaten up over an 8 year life, partly due to the use of auto fuel.
This is an updraft carburetor, with a venturi above the throttle flap. The main fuel metering jet is at the base of the venturi.
This exchange carb had a new one-piece venturi, which was produced to meet an AD from a few years back. The AD originated because several two-piece venturis disintegrated and fragments were ingested by engines, resulting in damage to engine internals, which is something that will probably get your attention and (as the old saying goes ) probably just about ruin your day...
At one time all carbs of this type were required to be retrofitted with the one-piece venturi. They then changed the AD, so that older two-piece venturis could still be used, as long as the venturi was inspected at the Annual Inspection.
The problem is that the one-piece venturi gives poorer fuel distribution than the two-piece venturi. Given that fuel distribution in an O-320 is uneven from the get-go due to the inlet tracts not being the same length on both sides of the engine (the carb is not mounted on the engine centre line), this leads to really uneven fuel distribution. The problem is apparently worse at less than full throttle because the partially open throttle flap acts as a turning vane for the airflow, causing different airflows to the two cylinder banks.
For a long time I was convinced that a 25 degree difference in CHTs in my engine was due to differential cooling between the left and right sides of the engine. I even began to consider how I might equalize the CHTs by installing ramps in the lower cowling. However, the CHT picture changes if you start aggressively leaning. You can equalize the temps within 5 degrees across all 4 cylinders if you are prepared to go to the point where the engine is just starting to run more roughly. The EGT guages show that at this point, 2 cylinders are coming up towards peak EGT, while the other 2 cylinders are just heading down from peak towards lean of peak. Further leaning results in rough running, presumably because the LOP cylinders no longer have enough fuel.
I have been considering retrofitting fuel injection to the engine. However, I also began searching on the Internet for more data on the venturi issue. Automotive parts suppliers will sell you swirl devices that fit into inlet tracts and whose purpose is to make fuel/air mixtures more even. All sorts of claims are made for these devices, including 5-10% reductions in fuel consumption (yes, and I have a bridge that I want to sell you some time...). Testing by automotive experts has shown that many of those devices are of no use at all (except to fatten the bank balance of the vendor), others do apparently provide some benefit, although most of the fuel consumption improvement claims need to be treated with skepticism because they come close to violating some of the fundamental laws of physics and thermodynamics.
What I did find along the way was a bunch of very interesting information on the SuperCub web site. The SuperCub is used extensively in Alaska because it makes an excellent STOL bush plane. Also, because of the need for float capability in that area, many Cub owners have re-registered their planes as Experimentals, since they can then install custom float and amphibian hardware which is not approved for use on Certified aircraft.
Many of these SuperCubs are fitted with O-320 engines. Since they have the freedom to experiment with all areas of the plane, some experimental-category Cub owners have also been trying to improve the fuel distribution from the stock carburetor on their engines. Some owners went back to using the two-piece venturi. However one owner named Ed Spraker in Alaska went one stage further. He designed and fabricated a replacement one-piece venturi for the MS carburetor. This venturi has turning/swirl vanes machined into it, so that it helps to even out the fuel distribution. Several Alaska cub owners have tried it out and like it. It was even tested by Lycon in California, but they screwed up the entire testing process because they did not compare test results against the same plane/engine combination with the official venturi; thus the test results lacked a comparison baseline and no useful conclusions could be drawn.
I have contacted Ed to see if he can supply me with a special venturi. So far I haven't managed to talk to him because he is out on the North Slope doing road works (now that's a cold place at this time of the year). If I can get him to supply me with a venturi, I will install it, conduct some before and after testing, and probably write it up for inclusion in the Central States newsletter.

Ever since the engine was rebuilt in 2003, the oil consumption has been a concern. I have been losing 1 quart of oil every 2.5 - 3 hours.
Normally, this would indicate worn rings or sealing issues. However, the plugs are not oily, and a recent visual inspection of the cylinder bores showed no evidence of excessive oil fouling or ring/cylinder damage. This is an engine that was completely rebuilt with new pistons, rings etc. as part of an overhaul to make the engine "yellow tag" throughout, with all ADs complied with. The cylinders are chromed, which usually results in slightly higher oil consumption, but slower wear rates. The cylinders are the cylinders which were on the engine prior to overhaul; minor repairs were made to the exhaust valve area on 2 of the cylinders, and they were re-plated.
The engine has always had high oil pressure since the rebuild. If the oil is not completely warmed up, takeoffs result in an indicated oil pressure of 105 lbs/square inch. (I can't be sure that this is a true reading since the pressure guage has not been calibrated recently).
I have always suspected that the high rate of oil loss was not due to oil being burned in the cylinders, but that it was mostly due to oil being expelled from the breather. The breather currently exits in the right wing root. On long flights I always find oil on the lower cowling, and after 2+ hours the oil has run all of the way down under the rear of the boat tail. If I run the engine at high rpm for any period of time, I also find oil streaks on the prop after landing. This is clearly oil that has been expelled from the breather, not oil burnt in the cylinders.
18 months ago John Hooker fitted a Slime Fighter air/oil separator. This cost me over $150 from Spruce. However, the separator was not fitted in the correct vertical orientation due to hose constraints that existed at the time. In its current configuration it makes no measurable difference to oil loss.
I am going to adopt a Plan A. I will make 2 changes in the short term and evaluate results:

1. Re-position the existing air/oil separator to be vertical
2. Install stainless steel tubing clamped to the exhaust to re-route the breather outlet and vaporize material being expelled via the breather downstream from the separator

If (1) does not reduce the rate of oil loss, I will adopt Plan B. This will involve buying a more expensive air/oil separator (probably the M20). This air/oil separator has a separate return line for oil that condenses in the separator housing. The main installation priority will be to position the separator close to the engine (probably anchored to the engine baffle) so that its internal temperature stays above 212 F. This will hopefully result in water products blowing through the separator and out of the breather tube, instead of condensing and running back into the engine.
More on this change as I proceed.