It has been a while since our last blog post, so it's about time we gave you all an update on what's been happening over the past 3 months! It has been an exciting time which has involved a lot of organisation and preparation for components forward of the firewall, including the firewall its self. In the past few weeks we have taken delivery of the engine, engine cowling, engine mounts and firewall, as well as continued progress on the turtle deck & other small items (which we'll blog about next week).
The engine has arrived!
Our engine has finally arrived from Barrett Precision Engines, a Lycoming AEIO-540-X which produces 300hp at 2,700rpm. This engine has Combustion Technology 10:1 compression pistons, an Airflow Performance FM-300A fuel injection system, and BPE's very own cold air induction system which produces 1hp more than the SkyDynamics kit, apparently! The engine has also been alochomed instead of painted to help keep the weight down, which results in this beautiful gold colour that you can see below.
We are very excited to hang the engine and the good news is that there is room in the garage!
Trying to find the correct engine mounts, however, has been an interesting experience as I've discovered that the engine mount/vibration & motion control industry is very secretive.
As the Pitts S-1-11B is a rare aircraft, both Barry Mouts and LORD Mounts have no off-the-shelf information to say which of their products I need. I first contacted Barry Mounts to ask if they could help identify which mounts would be suitable, however their customer service representative that I spoke to could provide no information about their mounts - due to company policy - to help me make a decision. Their response boiled down to "we don't have any mounts listed for the s-11-b, therefore we can't help". Urgh.
LORD Mounts on the other hand, whilst still very secretive, was far more helpful. It had been suggested to me by a friend that the mounts used on an Extra 260, LORD J-7764-20, should do the trick. Whilst again I could find out no information about this engine mount, LORD suggested the J-7764-31 and actually explained that the -31 is 15% stiffer than the -20 which they would recommend for additional motion control. As LORD was rather helpful, and we're recommended to us, we decided to go ahead with them:
We want to do everything we can to help keep this aircraft as light as possible, and a great place to save weight is in the firewall. The firewall is the big lump of metal in between my feet and the engine, protecting me in case of an engine fire and the general heat & fumes coming from the engine bay.
Conventionally this is made from galvanised steel, which is very heavy in a sheet this size. Titanium on the other hand is far lighter, in fact this titanium firewall is 3.7kg's lighter than using galvanised steel.
That's all for now! We'll provide another update in a few weeks to hopefully show a completed turtle deck.