The last post talked about the stripped spark plug threads. Well, today I got the Time-Sert repair kit in the mail so it was time to see whether the repair would work. The Time-Sert repair starts with a thread tap that has an initial part that is the size of the spark plug thread and …
After mounting the stainless steel intake runners, I did a few test runs to adjust the AeroCarb needle. I’m not going to get into the results from those runs right now since they’re incomplete, except to say that it seems like when you plot the EGTs vs fuel flow, it doesn’t matter how you adjust …
The last post ended with a test run with the cowling on, almost melting the temporary Nylon 3D-printed intake runners. It was time to get to work fabricating the real ones. Once I had established that the engine ran well with the plastic ones, I had ordered four 90-degree, 2″ radius, 1.25″ OD mandrel bends …
Since the last test run had the engine running quite rich, I adjusted the carb a bit leaner and tried again. It was definitely leaner, but the differences are getting small enough that I think I have to let the EGTs settle for a longer time to get a stable reading. This means I’ll basically …
With the vacuum leak fixed, and with manifold pressure and temperature sensors, I was excited to try another test run. Unfortunately there is no video this time. The short story is that it runs really well. Static full-throttle RPM is a tad higher than it was with the leaky plenum, about 3230, but more importantly …
With the vacuum leak fixed, I was excited to try another test run. But first, a small side track. The “RDAC” box that connects all the engine sensors to the MGL Enigma comes in two flavors, one that has a manifold pressure sensor and one that does not. The one in N132EA does not, but …
Well, the good news is that I figured out where the vacuum leak is coming from. The bad news is that it’s the 3d-printed plenum itself that’s not anywhere near air tight. I guess I should have checked this more carefully, since the fact that 3d-printed parts aren’t water tight is pretty widely known. I …
Finally, almost 2 months after the initial intake experiment that indicated the need for a complete redesign of the AeroVee intake, we now have some data! After assembling everything on the engine yesterday, I test ran the engine today and the results, while not entirely perfect, are very promising. A full throttle run shows that the …
With the 3D-printing trials and tribulations overcome, I pulled the left half of the plenum off the printer. The two halves fit well together, so I proceeded to melt in the brass M5 thread inserts for the mounting bracket and the screws that hold the halves together. The plastic parts were now ready to be …
The last post ended with the test print of the plenum. This was a useful exercise as test fitting the plenum in combination with the “Lego” runners indicated some adjustments to the angles of the runners’ exits from the plenum. After fixing that, it was just a matter of printing them… … or rather, that’s …
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