P-70 in BVM bypass
#1
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From: , IN
This is a very snug fit. Hoping that someone has done this and has some input as to turbine position in the duct. I'm afraid that the obvious (easy) position is too far forward.
DC
DC
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From: , IN
That might be the better question. Since it seems that few have actually put a P-70 in a bypass, what is the recommended bypass dia.? These were sold to me as P-70 size but they do seem a bit small. Normally you would want the exhaust approx. 5/8" in front of the bellmouth. In a bypass situation, the 'front' af the bellmouth becomes rather vague. Even with a Funsonic in the same duct, you gain a great deal of room, but the exhaust is even further from the 'front' of the bellmouth.
Thanks for responding.
DC
Thanks for responding.
DC
#5
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From: Burnsville, MN
DC, I have two P-70's in BVM by-passes. One in a Bandit the other in a T-33. They are a very tight fit. So tight in fact that they prevent you from running a FOD screen if it extends beyond the cowling at all. They do how ever perform very well in the duct.
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From: Lubbock,
TX
BV makes a specific bypass for the P-70 which is a bit longer than the Ram 500 bypass. The diameter is the same, however. I used the Ram 500 bypass/P-70 combination in my BVM F-16 since the longer bypass did not fit as well. The combination works fine and the engine runs cool. I did use BV's P-70 pipe in this application as well. The RAM 500 tailpipe setup has smaller diameter inner and outer pipes than the P-70 setup. and it seemed to be somewhat restrictive. With the P-70 pipe you can trim about 1/4" to 3/8" off of aft end of the bypass. This will open up this area a bit more and allow more air flow for cooling between the inner and outer pipes.
Mike Danchak
Mike Danchak
#8
I am debating whether or not to put a bypass in my jet. I would like to know the weight of the bypass and cover. If someone has a bypass out of their airplane, could you let me know the weight and brand. I am interested in a bypass for a p60 or p70 or 54mm class turbine.
Thanks,
Greg
Thanks,
Greg
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From: Baton Rouge,
LA
worse thing that will happen is the P70 will run cold if the bypass is too small... Tail pipe
size is far more important..
Even if it does run too cold, you may not notice, thrust and fuel burn will be down a bit..
size is far more important..
Even if it does run too cold, you may not notice, thrust and fuel burn will be down a bit..




