Carl Froehlich
Well Known Member
I keep looking at the much improved RV-14 lower cowl with envy. The significant drag reduction from this design should be a good model to replicate on the RV-10.
I’m curious if anyone has gone down this road. My thinking:
- A horizontal injected Cold Air Sump IO-540 can be ordered from Van’s. This would support a flatter bottom (like was done on the new RV-14 cowl). Talking with Lycoming they report the standard compression Cold Air Sump engine cranks 275hp as compared with 260hp on the standard vertical induction engine. I suspect the standard compression will support burning 93 ethanol free mogas.
- Cutting off the bottom exit area of the cowl and making the exhaust tunnels would be a pain, but clearly doable. The lingering question would be if the existing exhaust will still fit. If not perhaps Vetterman can come up with a new crossover design that does.
- I’m thinking that a movable cowl flap can be installed between the aft edge of the nose gear and the firewall. If not there than two smaller ones on each side of the bottom cowl. This would be a nice feature to keep climbs cool but closed for drag reduction during cross country.
For those who missed it, here is the very well done video on how Van’s came up with the new RV-14 cowl: https://www.eaa.org/Videos/Webinars/Aircraft-Building/6207071245001
Carl
I’m curious if anyone has gone down this road. My thinking:
- A horizontal injected Cold Air Sump IO-540 can be ordered from Van’s. This would support a flatter bottom (like was done on the new RV-14 cowl). Talking with Lycoming they report the standard compression Cold Air Sump engine cranks 275hp as compared with 260hp on the standard vertical induction engine. I suspect the standard compression will support burning 93 ethanol free mogas.
- Cutting off the bottom exit area of the cowl and making the exhaust tunnels would be a pain, but clearly doable. The lingering question would be if the existing exhaust will still fit. If not perhaps Vetterman can come up with a new crossover design that does.
- I’m thinking that a movable cowl flap can be installed between the aft edge of the nose gear and the firewall. If not there than two smaller ones on each side of the bottom cowl. This would be a nice feature to keep climbs cool but closed for drag reduction during cross country.
For those who missed it, here is the very well done video on how Van’s came up with the new RV-14 cowl: https://www.eaa.org/Videos/Webinars/Aircraft-Building/6207071245001
Carl