hecilopter
Well Known Member
I'm helping a buddy finish up his -7A and remembered a few simple tricks that I used and picked up from other's advice/forums etc. and thought I would reiterate them here while on my mind in case anyone else is finishing up
1. Don't forget to fiberglass the inlets on the upper cowl closed either on the inside or outside. This keeps air from leaking under the inlets and causing drag/cooling problems.
2. Put a thick washer between the baffling and the #3 cylinder in the back. This lets air circulate all the way around the cylinder and keeps it 10-15 degrees cooler.
3. If mounting the oil cooler on the baffle behind #4, put a supporting piece of angle attached from the baffle close to the oil cooler and run diagonally across to one of the engine case bolts. This strengthens the baffling and keeps it from cracking due to vibration.
I'm sure other people have some other tricks, but these are simple to do and result in a stonger/cooler/faster airplane. I'm very surprised they haven't found their way into the construction manual. I have been amazed in looking at some other planes that the upper inlets have not been closed off. It isn't in the instructions, but it makes a BIG difference cooling/speed wise.
Tailwinds!
1. Don't forget to fiberglass the inlets on the upper cowl closed either on the inside or outside. This keeps air from leaking under the inlets and causing drag/cooling problems.
2. Put a thick washer between the baffling and the #3 cylinder in the back. This lets air circulate all the way around the cylinder and keeps it 10-15 degrees cooler.
3. If mounting the oil cooler on the baffle behind #4, put a supporting piece of angle attached from the baffle close to the oil cooler and run diagonally across to one of the engine case bolts. This strengthens the baffling and keeps it from cracking due to vibration.
I'm sure other people have some other tricks, but these are simple to do and result in a stonger/cooler/faster airplane. I'm very surprised they haven't found their way into the construction manual. I have been amazed in looking at some other planes that the upper inlets have not been closed off. It isn't in the instructions, but it makes a BIG difference cooling/speed wise.
Tailwinds!
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