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RV-14 Engine options/firewall forward

irontrack

Member
Hey all,
I read the kitplane article which describes the performance improvements from the new io-390 215hp engines. In it they say that most of the improvements are from the exhaust / firewall forward changes.

Does this mean that you can get most the improved performance, with an io-390 A or other less expensive engine? Or, are these firewall forward improvements only viable for the new 215 io-390?
 
I'm pretty sure that some of the cowling change is because of the EXP119's cold air sump as well as the exhaust changes. Pretty sure I've heard that the new exhaust won't work on the 390A. For both of those reasons, therefore, you can't use the new lower cowl on the on the 390A.

However, one of the other changes is the new cowl flap and the closing of the tunnel. Reduces cooling drag. If you're using an exhaust that doesn't exit through the tunnel, you can install that mod.

Been a little while since I read about the changes so I might have some details wrong. If anyone has any corrections or additions, please chime in.
 
I'm pretty sure the answer is no, and if you have the time, this video over at EAA is worth the watch. I think what you're asking is a specific question addressed in it. IIRC, the new engine setup is physically different from previous configurations, and it was impractical to make others work.
 
I had already ordered my standard 390 Thunderbolt and finish kit when the Exp was announced. I had already decided to go with the Vetterman dual exhaust so I am incorporating the tunnel close off and cowl flap. Van’s sells this as a complete stand alone kit for $250. I like the idea of pilot controlled temps and according to the above mentioned video closing the Centre tunnel reduces the cooling drag considerably.
 
I like the idea of pilot controlled temps and according to the above mentioned video closing the Centre tunnel reduces the cooling drag considerably.

I really like to see this done by some one and get the result of reduced drag but also the effect of cooling it has for the oil temp. Many 14s already running a bit hot on the oil temp and closing the exit will probably add to that but unclear by how much.
 
I really like to see this done by some one and get the result of reduced drag but also the effect of cooling it has for the oil temp. Many 14s already running a bit hot on the oil temp and closing the exit will probably add to that but unclear by how much.

It should be interesting. The area for air flow might not be less as there will not be the single exhaust and its components in the tunnel. I’m installing on a new build so will not have the before to compare with.
 
I really like to see this done by some one and get the result of reduced drag but also the effect of cooling it has for the oil temp. Many 14s already running a bit hot on the oil temp and closing the exit will probably add to that but unclear by how much.

One of the other changes which can be incorporated on the 390A is 5" scat tubing to the oil cooler. Not sure if they're using a different oil cooler.
 
One of the other changes which can be incorporated on the 390A is 5" scat tubing to the oil cooler. Not sure if they're using a different oil cooler.

No change to the oil cooler as far as I know and the 5" scat tubing has been somewhat of a disappointment. I along with another person have installed the 5" scatt tubing and I saw only about 5F reduction in the oil temp. The other person who had reported his finding here, saw no change at cruise speed and only about 5F at lower speed.
 
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