VW-derived aircraft engine | Aluminium Cylinders
Steve Bennet has started to market Nikasil treated aluminium cylinders with a 94mm bore. Then there is this VW aero engine kit salesman that once more (with his usual two year delay) follows Steve's lead.
these bores leaves precious little metal between the bore and the cylinder head stud holes. More over the reduced landing area between the cylinder and the deck is so small that guaranteeing long lasting seals is difficult at best.
There are actually three 'classes' of Nikasil treated aluminium cylinders on the market:
- the 'below $1000 per cylinder/piston set' - These are cast aluminium jobs from China. Some Sonerai folks have discovered that the surface fitting between the cylinder and the deck leaves something to be desired.
- the 'around $2000 or slightly above per cylinder/piston set' - Cast aluminiuam as well, these are made by Mahle or other reputable manufacturers
- the 'Nickies', made by LN-Engineering by machining from a billet of forged alumunium. For a Type-1 VW engine, a cylinder-set will set you back around $2000. But wait, there is more! You'll be wanting their pistons and hardware set as well. Expect to be investing some $3000 for a complete set.
Apart from the weight savings, there is no technical reason to install aluminium cylinders on my VW aircraft engine. Since I'm dropping the electric starting option, my engine weight will remain within limits even with cast iron cylinders installed.
Rest assured that after this detour my choice is rather easy:
I'm going to install cast iron 90.5mm cylinders.
Also check out: VW-derived Aero Engine >> Type-1 Engine Case