Lufthans
Well Known Member
Hi guys,
I own an RV3B that is now taken apart for some serious upgrades. I’m a multiple offender when it comes to building and modding aircraft (and cars for that matter) and am going to put a Subaru conversion on the RV.
Not here to discuss the merits of this engine. There’s other places on VAF to do so. Suffice to say that I’ve been flying one on my Jodel for the past 15 years, which after three iterations, tons of engineering, money and headaches, I got to function flawlessly and thus far 100% reliably. I have done a few more on other aircraft since and even got to do some serious R&D for an Oregon-based company (not the mothership, there are more companies in Oregon).
Anyway, on the RV3, I will be putting the cooling in a P-51 style belly pod, with proper ducting, and will turbocharge the engine. With that (and modified electrics, fuel system, custom ECU, engine mount, cowlings, instrumentation and a whole bunch of upgraded engine internals), it has the potential of putting out 300 hp.
And here’s where my questions in the Rocket forum come in:
I know that 300 hp is serious overkill on such a small aircraft, and I know that its 210 mph Vne can be reached with half that power. So I will be using the other half to make it climb like a mountain goat with ambitions (which really suits my type of flying anyway - quick dashes to the clouds, play around between them and then drop back in).
However - it would be nice to have a bit more headroom in the speed department.
I’ve sent an email to John Harmon (with much of this text), however am not sure if I can expect an answer from him, since he’s apparently no longer supporting the HR-I. So I also post the questions here:
Does anyone here know anything about the specifics of this aircraft?
What did John state as a Vne on the HR-I, and what did he do to safely achieve that?
I believe he’s switched to an RV4 tail? Just for the sake of its mass balancing, or is it stronger too? Just the horizontal or the vertical tail as well?
Did he do any other structural modifications to the airframe like thicker skins? Did he modify the wing in any way? (Mine has the B-wing). (And yes, I know about the razorback, I just like the P-51-like looks of the slider more)
Bolting on a more powerful engine is one thing, but making it safe to operate is another thing altogether….
Curious to know and any tidbit of info more than welcome!
Thanks
I own an RV3B that is now taken apart for some serious upgrades. I’m a multiple offender when it comes to building and modding aircraft (and cars for that matter) and am going to put a Subaru conversion on the RV.
Not here to discuss the merits of this engine. There’s other places on VAF to do so. Suffice to say that I’ve been flying one on my Jodel for the past 15 years, which after three iterations, tons of engineering, money and headaches, I got to function flawlessly and thus far 100% reliably. I have done a few more on other aircraft since and even got to do some serious R&D for an Oregon-based company (not the mothership, there are more companies in Oregon).
Anyway, on the RV3, I will be putting the cooling in a P-51 style belly pod, with proper ducting, and will turbocharge the engine. With that (and modified electrics, fuel system, custom ECU, engine mount, cowlings, instrumentation and a whole bunch of upgraded engine internals), it has the potential of putting out 300 hp.
And here’s where my questions in the Rocket forum come in:
I know that 300 hp is serious overkill on such a small aircraft, and I know that its 210 mph Vne can be reached with half that power. So I will be using the other half to make it climb like a mountain goat with ambitions (which really suits my type of flying anyway - quick dashes to the clouds, play around between them and then drop back in).
However - it would be nice to have a bit more headroom in the speed department.
I’ve sent an email to John Harmon (with much of this text), however am not sure if I can expect an answer from him, since he’s apparently no longer supporting the HR-I. So I also post the questions here:
Does anyone here know anything about the specifics of this aircraft?
What did John state as a Vne on the HR-I, and what did he do to safely achieve that?
I believe he’s switched to an RV4 tail? Just for the sake of its mass balancing, or is it stronger too? Just the horizontal or the vertical tail as well?
Did he do any other structural modifications to the airframe like thicker skins? Did he modify the wing in any way? (Mine has the B-wing). (And yes, I know about the razorback, I just like the P-51-like looks of the slider more)
Bolting on a more powerful engine is one thing, but making it safe to operate is another thing altogether….
Curious to know and any tidbit of info more than welcome!
Thanks