RVG8tor

RVG8tor

Well Known Member
Any one out there put in a float tube on a QB tank? I am building a -8A and want to add the flop to one tank, Van's said it is doable but I did not get into specifics. Is this a simple operation or will I have to disassemble some or all of the tank? Along the same lines, are the fuel senders (floats) Van's sell durable or is there some other manufacturer of floats builders prefer?

Cheers
 
No too bad....

I did this a few months back on my 7. I removed the end rib for better access. This was mostly due to the need to reach through the second rib for mounting the fuel sensor and mount the 90deg fitting in the nose of the first rib.
Made a doubler out of the original end inspection plate for the new fuel sensor position on the back of the tank as it already had the proper plate nuts installed. Replaced the end plate with a blank panel. The only part I needed from Vans was the end of the flop tube.
 
Did a flop tube thru the access hole on a QB tank. Look out for the hidden rivet under the proseal prior to drilling for the 90 deg. fitting that the flop tube mounts on; look at plans for position. Not that bad of a project.

T.S.
7A
ready to mate wings
 
I have dual flop tubes on my RV-7. The RV-8 I'm building will have NO flop tubes. No point in having them unless you have an inverted oil system for your engine. And even then, are you really going to spend that much time with NEGATIVE G? I'm not talking upside down, because I get upside down ALL the friggin' time. I'm talking true negative G sustained. Be realistic about your intentions...cuz I wouldn't bother!
 
I agree with Dan

Know your intentions.

Personally I love doing -ve G stuff but would I put invert everything in again?....Hmm. Its definately chasing the last 1 percent of the flight envelope thats for sure.

I personally enjoy exploring the -ve G stuff but I too would think hard before I installed it all again.

Frank
 
Neg "G" during BFM

I am hoping to do some light Basic Fighter Maneuvers (BFM), hence the want for negative G fuel oil system. I have a friend who goes out with his hanger mate and do formation and some BFM against each other. He does not have the negative G setup and sometimes losses out due to this. A negative G push over does wonders do mess up a tracking gun shot. Maybe this is over kill. The expense of the inverted oil system is high the flop tube is like $40. I guess I will keep thinking on this.

Any others out there doing any BFM with their RVs?

Check Six
 
Hmm ya

RVG8tor said:
I am hoping to do some light Basic Fighter Maneuvers (BFM), hence the want for negative G fuel oil system. I have a friend who goes out with his hanger mate and do formation and some BFM against each other. He does not have the negative G setup and sometimes losses out due to this. A negative G push over does wonders do mess up a tracking gun shot. Maybe this is over kill. The expense of the inverted oil system is high the flop tube is like $40. I guess I will keep thinking on this.

Any others out there doing any BFM with their RVs?

Check Six
Click to expand...


I know these motors are supposed to be just fine with losing oil pressure momentarily...But purely personally I'd rather have oil pressure ALL the time.

The other option is to stick a 1.5 quart oil accumulator on your oil system. Will weigh a bit less, will be cheaper and will provide a few seconds of -ve g without losing oil pressure.

Just a thought.

Frank 7a
 
i disconnected the Christian inverted system after chasing the low oil pressure; people said 10-15 psi lower is normal but I just plugged it off and will chase down a correct shim,shaft,rod for the back of the case or whatever later.

also, might want to make sure your flop tube-- flops. the tube we have, which I assume came from van's was just stiff enough that it wouldn't bend all the way.

we pro sealed a heavy fishing weight to it.

the only benefit so far with the flop is making me remember to switch over to the non flop side for extra safety on prelanding check.
fwi

edi- btw it sounds like you have a good reason for a flop.
 
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