Question for smooth cowl owners

I know this topic has been hashed and rehashed but...

I'm ready to order my engine... I love the looks of the smooth cowl (already have one) and was planning to purchase IO-375 with horizontal cold air induction. I was taken back to learn that mufflers were not possible in this configuration but was even more concerned to hear that the heat muff may not be adequate for cold weather. My questions are for those with a smooth cowl.

1) Do you get enough heat?
2) Is the noise an issue?
3) Do you regret your decision?

Thanks for taking the time to answer!

Mark Bengel
RV7 - Nashville, Tennessee

I have the IO-375 as well with the Vetterman four pipe exhaust system. The heat muff for this arrangement encompasses two pipes, and I've heard this provides sufficient heat. I'm not flying yet though, so I can't verify this.

IO-360-M1B with the smooth cowl. I was initially bummed when I found out about not having mufflers availible with this set up. I have the stock set up with only one heat muff. The only mod I did was to reduce the size of the inlet for the heat on the baffle intake. The heat is not overwhelming by any means, but I have yet to find it too cold. At temps in the 20's F, I am comfortable in a sweatshirt with no gloves. My canopy seals very well and I don't feel any drafts, if I stick my hand in front of the closed vents (Steins) I can feel a touch of cold.

1. yes, though I may add another heat muff at some point in the future on another pipe.
2. No. I do have a set of Zulu's, and it's fine.
3. No

Good luck Mark

I too like the smooth cowl look, however when purchasing the engine a repeat builder (many times over) and RV encyclopedia mentioned the ram effect and boost in MP with the vertical intake. Just something to think about if it comes down to a cost/benefit analysis. Plus the engine was too good a deal to pass up, so vertical intake it is.

There is room to put two heat muffs under your smooth cowl. I have one and there is sufficient heat until the OAT gets below 25 degrees. Cutting down on cockpit air leaks really helps keep the heat in.

Muffler? Why would you need a muffler? ANR headsets are routinely used in RV's. Don't airplanes and noise go together like peanut butter and jelly?