Exit Fairings

Somewhere in the past a post began with "I finally got 170kts out of my O320 RV7A". It went on to discuss the virtues of a fairing that had been placed forward of the exhaust pipes where they exit from he cowl.
A better memory or better search skills would be handy at this time. Can anyone remind me?

regards

Jeff H
N377CP, KWVI
16 hrs remain in phase 1

Exhaust

Look on the Vetterman Exhaust web site for some info.

I smoothed up and curved the exit of my lower cowling in addition to a lower firerwall radius on my 7. I reduced the exit size by about 15 square inches and have kept the same CHT's and oil temps. I did see a couple knot speed gain, but I believe I have more to gain when I cut the old cowling scoop off and smooth everything out.
A little harder to make this way, but very little downtime and easy to cut out and start over if I didn't like the results.



You can see my firewall radius here, the lower cowling fits against it.