I don't have my engine yet (it's been on order for 2 years!) but I'm planning to put an IO-390-EXP119 at the front of my RV-7. I'd like to start laying out the firewall and mounting some of the components, but obviously without the engine it's a bit tricky. Does anyone have a diagram of the layout they used, or some photographs please? I'm planning to use the Showplanes 13-row oil-cooler mount (which attaches the cooler to the engine mount just aft of cylinder #3) so that will free up some firewall space. The prop governor will be at the front on the left side, and I will have the AFP FI system, with the Andair pump in the cabin. Any help gratefully received - thanks in advance.
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Firewall Map or Pictures for IO-390-EXP119
- Thread starter AndyWW
- Start date
KeithB
Well Known Member
You might get some ideas from the RV14 plans as it is built around the 390. I realize there are many differences, including dimensions, but lots of similarities too.
Desert Rat
Well Known Member
I installed an IO390-A3B6 in my RV7. I have a 13 row oil cooler mounted to an RV10 plenum on the l/h firewall so it's not exactly the same, but there are pictures in my build log that might be helpful. I learned a few things along the way that would cause me to change some stuff if I were doing it again.
If you're using the showplanes oil cooler mount then you might consider moving the battery and associated contactors to the l/h side just so the hot air out of your oil cooler isn't blasting on them.
I used the RV14 engine baffles because somebody told me they were pretty much a direct fit. I wouldn't do that again. They fit the engine perfectly, but there was lots of trimming to get them to fit under the RV7 cowl and quite a few of the predrilled holes for attaching the baffle rubbers were in exactly the wrong spot because of that. I also had to change teh width of the inlet ramps to get them to better match the cowl inlets.
I was able to use off the shelf Vans control cables. I don't remember without looking, but I want to say that the throttle and mixture cables were from a RV7 angle valve installation and the prop cable was from a RV14. It took some experimentation to figure out what lengths and where to do the firewall penetrations for them. I shouldn't have done the firewall penetrations until I had the engine loosely trial fit to the mount. I thought I had it all figured out but ended up with one cable routing that didn't make sense and ended up having to change where the cable was coming through and patch the previous firewall hole to make everything work.
Things like fuel and oil lines were mocked up with vinyl tubing and then once I had the lengths and routing right I ordered them custom made from TS flightlines. I skipped the firewall mounted manifold that Vans sells and just mounted the engine sensor transducers on the engine mount tubes which let me have shorter hose runs to them and freed up some space back there.
I should have installed the spark plug wires before all the sensor wiring. There are only so many ways you can route those spark plug leads. It's a lot easier to route the sensor wiring around spark plug wires than the other way around.
It's not like any of it is super complicated, but I will say that more than once I found myself wishing that I had just gone with a parallel valve 180 hp. When you go off the reservation like this it seem like everything you just installed gets taken back off because you discover it' s now in the way of the next thing you need to install.
I used a Vetterman crossover exhaust and it bolted right up no problem
If you're using the showplanes oil cooler mount then you might consider moving the battery and associated contactors to the l/h side just so the hot air out of your oil cooler isn't blasting on them.
I used the RV14 engine baffles because somebody told me they were pretty much a direct fit. I wouldn't do that again. They fit the engine perfectly, but there was lots of trimming to get them to fit under the RV7 cowl and quite a few of the predrilled holes for attaching the baffle rubbers were in exactly the wrong spot because of that. I also had to change teh width of the inlet ramps to get them to better match the cowl inlets.
I was able to use off the shelf Vans control cables. I don't remember without looking, but I want to say that the throttle and mixture cables were from a RV7 angle valve installation and the prop cable was from a RV14. It took some experimentation to figure out what lengths and where to do the firewall penetrations for them. I shouldn't have done the firewall penetrations until I had the engine loosely trial fit to the mount. I thought I had it all figured out but ended up with one cable routing that didn't make sense and ended up having to change where the cable was coming through and patch the previous firewall hole to make everything work.
Things like fuel and oil lines were mocked up with vinyl tubing and then once I had the lengths and routing right I ordered them custom made from TS flightlines. I skipped the firewall mounted manifold that Vans sells and just mounted the engine sensor transducers on the engine mount tubes which let me have shorter hose runs to them and freed up some space back there.
I should have installed the spark plug wires before all the sensor wiring. There are only so many ways you can route those spark plug leads. It's a lot easier to route the sensor wiring around spark plug wires than the other way around.
It's not like any of it is super complicated, but I will say that more than once I found myself wishing that I had just gone with a parallel valve 180 hp. When you go off the reservation like this it seem like everything you just installed gets taken back off because you discover it' s now in the way of the next thing you need to install.
I used a Vetterman crossover exhaust and it bolted right up no problem
Thank you very much Terry & Keith. I've already bought the RV-14 baffle kit so I guess I'll be modifying it as you did. I was planning an EarthX battery on the left side - I have to decide whether to use the "Compact" version (ETX680C) or the standard one (ETX680). I'm hoping that the forward prop governor and the Showplanes oil cooler mount will give me a reasonable amount of space on the firewall. I'm planning to measure the control cable lengths one I have the engine mounted and hopefully get them in the UK. I do plan to use the Vetterman exhaust. Thank you for the tip on the spark plug wiring.
Andy
