Does anyone know if a Thunder Tiger 46 Pro will come on to a pipe?? Thinking about one for a pattern plane but i'm greedy for performance so I want a pipe. Thanks in advance

Hi!
Of course it will ..like most engines will!

Regards!
Jan K
Sweden

Ok, thanks very much, I'll give it a go. Do you know of a reliable method for finding the starting length, I've got a piped 48 on another plane and everyone tells me to do different things, one told me it was too short, so I lengthened it, then another (semi-pro) told me to make it even shorter than it was before???!!!! I did find a formula on an Australian pattern site but that didn't seem to help.

Oh, the joys,
Thanks for the help.

http://www.macspro.com/tuning.asp
Read these?

You will need to run a smaller prop so the engine will get up into the rpm area where the pipe will be more effective.

Enjoy,

Jim

Excellent, thats EXACTLY what im looking for. And looking at that i'd say my 'even shorter' pipe is still too long. Problem is, with it being for a pattern model, noise is a big thing, and I don't really want it spinning at stupid revs, was hoping to load it up a wee bit and keep the revs down to about 11k? any thoughts?

Hi revs = short pipe

Low revs = long pipe 11,000 is low

Enjoy,

Jim

If you are looking to turn only 11k with the TT .46, you surely dont need a tuned pipe. Tuned pipes are generally is for seeking high performance at high speeds. Generally "tuned" for a small range of rpms. I doubt the TT .46 running a pipe at 11k will affect the performance of your pattern airframe. I'd stick with the stock muffler.

Well said

Enjoy,

Jim

It was just to turn a bigger prop comfortably. Was looking for 12x7 to get some decent performance out of the verts, but ok. Cheers for all input guys.

Running at 11,000 you will not get enough from a pipe to make it worth the expense.

You get up to 15,000 and the pipe will do some work for you.

Enjoy,

Jim

11,000 is very close to the revs usually turned with piped engines in CL stunt. An OS 40VF with a pipe at these revs (set at about 18" from the plug to the first baffle) is considered by the experts as having roughly the power of a muffled 60. In this application the pipe is boosting torque at around the peak of the torque curve which means you can turn a bigger prop. This is what was done with the old OS Hannos to make them turn a 12x12 prop (at even lower revs, something like 9,000). The other thing the pipe then does is if the engine tries to speed up when prop load decreases in a dive then it goes off the pipe and holds the revs more constant so it's a governing device as well.

I've been waiting for you to say that. I read this in a magazine some 15 years ago but have never heard it repeated since.

I've thrown this theory up on here several times and no one ever responded good bad or ugly.

Thanks,

Jim

The Tower muffler is an easy bolt on performance enhancer @ $15- The Ultrathrust or Jettstream would do better but more $$

Is the "piped-48" a K&B Screamin' 48? I love those...

If I tell you, you gota promise not to laugh?

Ok, (whispering) it's an mds. Shush, don't tell anyone.

This is what I've been looking for. I knew the pipe would have to be long, but 18inches? [X(] As to the governing factor, this is a very clean airframe without the drag needed to fly constant speed style pattern so thats gonna help plenty.

I know this plane flies much better on a 60, but I've already drilled the firewall for a 40 mount, and a pattern plane without a pipe is like pancakes without syrup.

I knew something like this existed, the OS 140 that was/is used for pattern has a pipe about two foot long but runs at low revs, just didn't wanna open my gob in case I put my foot in it.

Last quote, I promise
I've already got a pipe to use so I'm just trying to use what I got.

Thanks again guys, this is a lot better than I could have hoped for. [8D]