dredknot

Hello Guy.

I'm new to this Forum i spend most of my time in the 3D forum.
I just got a viper 500 and wanted to know which engine would give for the best performance and how big a diffence between the ,Thunder Tiger 46 or OS fx46.
I also plan to use Macs Pre-Tuned Muffler Tuned Pipe.

thank you

vicman

My Feedback: (10)

Either engine you mention would work great. Both will pull you along faster than any 3D plane you have ever flown. I like both engines but the price of the TT a little better. If you choose the TT give strong consideration to replacing the rear bearing before you go hypersonic. The stock one has been prone to letting go at high RPM.[8D]

dredknot

it better move a whole lot faster than a 3D plane vic man ,thanks for your help

vicman

My Feedback: (10)

You will easily see a buck twenty and more out of a dive. Put a 9X8 APC on there.

dredknot

great

B EXTREME

I personally like the FX. it is such an excellent engine, well made, well behaved, well designed but if you want performance than i would go with the TT46. from what i have read the Thunder Tiger seems to rev a little higher than the os but, as far as engine quality goes it isn't as good. it is up to you want you want to do. if you were assembling it as a practise pylon plane or a pylon plane than you would put the OS in it, if you are setting it up for oughtright speed than put the TT46 in. i have seen a few done with both of the engines and there isn't much between them (speed wise) but in my opionion the TT46 is just that little bit faster.


have you also taken a look at some of the pages on the the viper, you will find that it is one of those FIX IT BEFORE YOU FLY kinda planes

they do fly great after you fix a few things up

this will outline most of the issues they have. it is also very helpfull in the building stages aswell

http://www.rcpro.org/html/articles/q...500_by_don.htm


good luck....get ready for some speed[>:]

bob27s

My Feedback: (19)

Thunder Tiger 46 pro

Use a Jett-stream muffler instead of the long pipe. Just bolt it on.

No cutting or tuning. Much easier to install, less drag.

Performance of this combination is well documented. I recommend it often.

Just break it in for 15 minutes with the jett-stream and a 9x6 installed. Fly it with a standard APC 9x7.
Find peak rpm, back off 600-700 rpm for flight.

16,500+ ground peak rpm is easy.... and you will have a 130mph+ Viper.

Other prop selections work well too. The 8.8x8.5, 8.75x8W and 8.75x7.75 racing props work well too

The OS46FX gives similar performance.
So it is somewhat of a toss-up and comes down to personal preference... and whether you have an engine on hand already.

My personal preference is the TT46pro.

cmircman

My Feedback: (10)

I second what Bob said as I have this combo and love it. I just need to order the jet-stream muffler for it and I am positive I will gain a easy 1000 rpm.


Rich

freakingfast

My Feedback: (3)

The motion is carried. Bob is the “answer man�.

panzerd18

55AX?? Anyone??

cmircman

My Feedback: (10)

I would stay with the 46 as the 55AX is not a rpm motor. The 55 makes its power at 14000 rpm.

airraptor

My Feedback: (66)

the tower mufflers are good too and 1/3 the cost of the jett/nelson muflers but dont give the same rpm maybe about 3-500 less than a good jett red muffler.

bob27s

My Feedback: (19)

They do work, and it is a good inexpensive option.

It is not a true tuned device - the tuning effect is "incidental" for lack of a better term - the boost effect is around 16,000 rpm. That is ground peak rpm.

In flight, there is a larger performance difference between the tower muffler and a jett or ultrathrust muffler.

dredknot

Thank you guys,I have an used fx already also got a Macs Pre-Tuned Muffler Tuned Pipe from a friend,
Question,
there is no nipple on the Macs Tuned Pipe to attach trubbing to,what is the best way to get fuel to the engine.perry pump, Crankcase Pressure.help needed,i have no idea which is best.
way to much Gasser

bob27s

My Feedback: (19)

Install a pressure fitting in the pipe just forward of the weld steam, or drill and tap the mounting flange of the header for a pressure fitting.

dredknot

thanks,bob