If it ain't broke, don't fix it!

The Giles G-200 was going well last year. No squawks, all sorted, going really well. I flew the NSW Champs at Temora and immediately afterward went to Tamworth and got my Unlimited LLP with the CASA-man. Full steam ahead for a solid summer of training with a view of maybe moving up to Unlimited in 2011.

But, the A$ was so strong - what could I buy? I HAD to take advantage of it. So I ordered a Sky-Dynamics sump, cold air intake and 4-1 exhaust. I didn't NEED any of this, the 'plane had more performance than I could currently use, my only concern on occasion was oil pressure drops. Regardless, off went the money and in due course it all arrived. Merry Xmas to me..
In between harvest and New Year I fitted it all up, changing some cable runs and oil cooler hoses etc, all with the goal of less weight and less complexity. I was really happy with the finished job - neat, sanitary, light and simple! There was only one problem - it ran like crap. Rough, some cylinders lean, some rich. At WOT it felt like two cylinders dropped out altogether. Horrible it was, really bad. And it was hotter. Oil temps had always been marginal, now they were over redline after a sequence on a warm day.

I tried to sort the problems, but nothing really helped. I suspect oil temps were up due to the loss of cooling from the fuel/air mixture going through the sump, and maybe a hot cylinder or two.
The cold-air intake with no plenum, no heat from the oil and sharp bends to the intake tubes just would not play nicely with the Ellison TBI I'd used with success up to then.
So what do I do now? Put it back to original? I'd trashed my old inverted oil lines to make the new ones. I'd spent the money....and the exchange rate is so good, right? So.........
I investigated fuel injection options and ordered an Airflow-Performance FM-150. Delivery will be six weeks....what! So much for Summer training.

Eventually it arrived, after only three weeks, and I started installation. Not as straghtforward as you would like. Due to the previous mixture conniptions, I'd bought and installed a 4-channell EGT gauge. I also had to change the low-pressure electric boost pump (Facet - simple cheap type) for a high-pressure one (Weldon - heavy, dear). Luckily I had the old one that was in the airframe when I bought it. The engine driven fuel pump also needed changing for a high-pressure type. More $$ and a bastard to change with the engine on.
And, surprisingly (or maybe not, it is an aircraft after all...) the servo orientation was limited by the Sky-Dynamics intake support struts, making the throttle and mixture cable runs more difficult, and putting the fuel supply and outlet ports in less-than-optimum positions. I thought being in neighbouring US States and this being a 'typical' acro combination, it would fit up sensibly.
Solution - simple, drive to Sydney (400km one way) and purchase special hose fittings to do what I needed.

Finally it is all on, and ground runs are complete. Seems to run OK. Not as tidy an install as the Ellison, and substantially heavier. I haven't weighed it yet, but it won't be sub-900lb as it was before. And the CG will be further forward.
So for my $X,0000 I got a heavier, less balanced aircraft! Maybe, hopefully, I gained a few HP and guaranteed oil pressure in all attitudes.

Somehow, I think my $$ would have been better spent on avgas. So, next time - if it ain't broke, don't fix it!

Postscript: So far two test flights and some gentle aeros. The A-P FI is doing as it should, only the idle needs adjusting up a little. EGT's mid 1200's at WOT leaning to mid-1400's before power goes down (my probes are 6-7" from exhaust flange). 25-30F max. EGT spread most of the time. The trim has changed, as expected. Time to boogie!

Aerobatic Aircraft

Any aerobatic aircraft will do to get started, so I won’t spend time on the basic aircraft here. Learn to fly whatever you have as well as you can, and learn the ‘craft’ of sport aerobatics on the way. There is a lot to learn. When you get to the stage of wanting/needing a more capable aircraft, then here are some options. I’ve stuck with the single-seat types as if you run an alternator and second seat you aren’t really serious....
If you have unlimited disposable income, you can skip this section!

Pitts S-1S,C,T,D: Very available at affordable prices. Lots of ‘corporate knowledge’ on how to fly one and their capabilities are well known. Flown hard they will require regular and ongoing maintenance. Four-aileron models needed for Advanced and symmetrical-section wings for Unlimited. Not truly competitive at Unlimited levels these days, but flown well on the right day can still be on the podium.

Yak-50: A classic aerobatic aircraft but getting hard to find at the right price.
‘Classic’ premium has overtaken their aerobatic price, I suspect. Can still perform well at Advanced level. Regular inspections needed on hard-flown examples.

Yak-55, 55M: Very affordable performance for the dollar, pity about the fuel and oil burn (as for Yak-50). Tight cockpit for tall pilots. Heavy ailerons and a big aircraft to push around the sky, and hangar. Good thrust to weight ratio, but drag makes them struggle at the higher levels.

SP-55: Rare but can be found at a good price on occasion. Should be competitive at Unlimited, but not in the league of the Sukhoi’s apparently.

Laser Variants: An excellent Intermediate/Advanced aircraft, though again will struggle at Unlimited. Price parallels quality of these homebuilt aircraft, and they hold their value well due to reputation and economical 4-cylinder engines.

DR-107: An excellent performing homebuilt capable of consistent Unlimited performances if built light and in the right hands. Economical to maintain and operate with good range and cruise speed to get to the next interstate competition. Can be bought for good prices in the US and imported. Buyer beware, of course. Drawback is time to build, if that is your desire.

Giles-200,202: Again, an excellent performing 4-cylinder design, unfortunately kits are no longer available new. Excellent performance for the dollar, but at the upper end of ‘affordability’ used, especially the two-seat model. Capable of Unlimited performance all day long. Excellent maintainability.

Edge-360,540S: The 360 is rare. The wire braced tail 540S turns up at a good price on occasion. The later cantilever tail model is hard to find and expensive to buy. They are very popular in the US but not used in competition elsewhere much (i.e. Europe). I think poor visibility is their weakest point compared to the European monoplanes.

Rebel, Staudacher, Hurricane et al: There were many ‘super-laser’ 6-cylinder machines produced during the 90’s in the US that can now be had for a good price. Most were conventional in construction (steel tube fuse, wire braced tail, wood/composite wings). Excellent value and Unlimited capable due to their high thrust to weight ratios, but may not have the roll-rate and handling qualities of the better respected machines.

CAP, MX, Sukhoi – go for it if you have the dosh.