MVVS 1.60 Glow rpm readings?
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MVVS 1.60 Glow rpm readings?
Hi chaps,
Does anyone have RPM readings for the MVVS 1.60 glow please?
I have a Bisson Pitts silencer on mine and am getting 7300 with an 18x6 wood prop on straight fuel. Just seems a bit low to me.
I'll try 5% at the weekend and see what difference it makes, but being high compression, they don't like too much nitro so 5% is about the limit for it unless I shim the head.
Does anyone have RPM readings for the MVVS 1.60 glow please?
I have a Bisson Pitts silencer on mine and am getting 7300 with an 18x6 wood prop on straight fuel. Just seems a bit low to me.
I'll try 5% at the weekend and see what difference it makes, but being high compression, they don't like too much nitro so 5% is about the limit for it unless I shim the head.
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RE: MVVS 1.60 Glow rpm readings?
The prop is a Just Engines own make, but I wouldn't have thought that would make over 1500rpm difference though.
Remember I am using Straight fuel. I'm wondering if I should cut off the end of the Bisson silencer outlets where they return in and use a Perry pump?
I'm only getting about 13.5lbs static thrust (using a fishing scale on tarmac surface).
Remember I am using Straight fuel. I'm wondering if I should cut off the end of the Bisson silencer outlets where they return in and use a Perry pump?
I'm only getting about 13.5lbs static thrust (using a fishing scale on tarmac surface).
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RE: MVVS 1.60 Glow rpm readings?
I went down to my local hobby shop at lunchtime, adn guess what "we're all out of 18x6 props"
I was really after a Zinger but I did have a look at APC's too - nothing. They're getting more in next week (apparently) so I guess I'll just try the 5% fuel at the weekend and see what difference that makes first.
I was really after a Zinger but I did have a look at APC's too - nothing. They're getting more in next week (apparently) so I guess I'll just try the 5% fuel at the weekend and see what difference that makes first.
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RE: MVVS 1.60 Glow rpm readings?
OK, with a Zinger 18x6 and 5% nitro I'm now getting 7800. This is a bit nearer what I was expecting.
Other options to improve things are:
1) Remove the rolled ends of the Bisson Pitts silencer and add a pump to compensate
2) Shim the head to reduce the compression ratio and go to 10% nitro.
I'll try the plane today (CMPro Giles 202 1.40 size) and see if the extra revs give me what I want.
Other options to improve things are:
1) Remove the rolled ends of the Bisson Pitts silencer and add a pump to compensate
2) Shim the head to reduce the compression ratio and go to 10% nitro.
I'll try the plane today (CMPro Giles 202 1.40 size) and see if the extra revs give me what I want.
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RE: MVVS 1.60 Glow rpm readings?
7800 rpm on a 6 pitch prop will give you a very slow max speed unless the engine unloads a great deal in the air. Good luck. There was another thread for this engine in this forum, you may want to compare.
Darzeelon started it.
Darzeelon started it.
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RE: MVVS 1.60 Glow rpm readings?
Hi Brian, I flew it yesterday and your absolutely right, it WAS slow. So I guess I'll be going back to the JE prop, which although it says it's an 18x6 I'm thinking its an 18x8 really. I might try a 16x8 and see if the revs improve.
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RE: MVVS 1.60 Glow rpm readings?
Pete 850,
Thats a ringed engine isn´t it? I think it may take much more time to break it in. I dont think using 10% nitro instead of 5% or 0% would give you more rpm, maybe only a few hundreds more and slightly better idle. APC:s also revs up much more than wooden props,but they are very heavy[]. Good luck/Amir
Thats a ringed engine isn´t it? I think it may take much more time to break it in. I dont think using 10% nitro instead of 5% or 0% would give you more rpm, maybe only a few hundreds more and slightly better idle. APC:s also revs up much more than wooden props,but they are very heavy[]. Good luck/Amir