Spectra-G Power System

[Sar]

Hi Guys, after taking your responses to my "Which Gasser" post into consideration and doing more research, I just ordered a Spectra-G with Tempest head today from my local shop (3DRC in NY if anyone processing back orders is watching )

I'm planning on using this heli for a hobby camera ship, experimental(avionics, projects, etc), sport flying, and simply to fullfill a boyish desire for a gasoline powered helicopter complete with gasoline engine smell and noise.

I see there are a variety of engine/exhaust options. There seems to be problems with the side mount exhaust vibrating off, and personally I think the MA rear mounted exhaust system would look better and more compact on this heli. I know right now that only the TRM G23 has been 'approved' for use for this heli, but I'd hate to spend over $400 for a G23, only to have the TRM G26 be approved a week after I buy the 23.(This stuff happens to me all the time!)

Is the difference in power between the G23 and the G26 going to make a huge difference to a guy like me who is going to be dragging some light equipment up in the air with his heli for experimental purposes(couple camers, some GPS gear, transmitters, batteries) and some moderate 3D? If I throw caution to the wind, what's the better choice? Hanson G26 Pro, Hanson G26 3D or the TRM G26. Is the MA rear exhaust going to cost me a lot of power over the the side mounted MA pipe?

And.. Stage I, Stage II? What the heck does this mean? I hate buying stuff and finding out that it's outdated and the newer version is only a few $$$ more. And right now there seems to be a lot of development in the Gasoline heli engine sector.

I attached a poll as well....

[WillJames]

TRM does not make a 23, it is a G 231 which is very different than the G23.

There is only one TRM Prototype 26 and it is going to be a LONG time before it makes production if it does. We are concentrating on the pipes and a lot of other things before we do anything with the 26. A TRM 260 is NOT going to come out right after you buy the 231 like you say John. Pipes will be hanging off all kinds of helis before TRM produces a production 26, if we ever do. You can take this info to the bank.

If you want a TRM Motor, then buy the 231. We have put much time and effort into getting to production. It is the smoothest, most user friendly with the widest powerband motor on the market in our opinion.Plus, as has been said before, if we do ever make a 26o you can send your motor back to TRM and have it converted for a minimal amount of $$. (Don't count on us ever releasing a G260 though please) TRM 231 and matched pipe that is my combo of chioce.

[Sar]

Okay, no TRM 260 in the near future... Narrows the list down some. I appreciate all input on this of course. I know I seem to ask a ton of basic annoying questions and 'user opinions' but with all the marketing hype I'm trying to get to raw data and build a complete picture.

Stage I, Stage II is this a racing term carried over to RC Engines, or what am I missing here. I know it has to do with port polishing, mods, etc. What defines something as stage II? Is that a manufacture saying 'this is as much as I will do for this stage' or are there goals such as % of performance increase, or certain kinds of mods performed.

Since these motors are modified for better performance and more power, how does this affect their usable lifespan(the point where you keep checking your carb settings wondering where the power went), and how many hours before a rebuild are you looking at?

[WillJames]

We are glad you are asking these questions John. You are far better off to research the subject thoroughly then purchase as an educated consumer. I wanted to make the point right off that the 260 is nowhere near production, and may never be.

I do know that power was the last concern. Overall user friendliness, smoothness and wider power range are the three primary design goals, and not power increase. I am no expert, but I think the power increase comes from the better balance of the motor due to the lightened/modded piston and the fact that it breathes more efficiently with the mods. Again, I am no expert on teh internal workings of the gas motor. I leave this to John and Al, all I do is test and enjoy.

The stage 1 motors have been extensively tested and are a very good combination of the TRM design goals wrapped into one mod package. I will ask Al about motor longevity. My estimation is that with a more user friendly motor that does not have to be needled on the ragged edge to get good performance out of it, motor longevity should be as good or better than the stock motor. Gas motors are not nearly as forgiving as glow motors. If you run your glow motor to hot,(lean) it will eventually shut down, but when it cools, unless yougot it EXTREMELY hot, it will still work. With a Gas motor, you stand a very good chance of damaging your engine if you run them to lean and get them super hot the first time it happens. That is just the way it is with Gas motors of any brand, modded or stock.

I will talk to Toxic Al and run this stuff by him to make sure what I have said is accurate. As I said, I am no expert, but I have worked with John and Al to do a bunch of testing over the last 6 or more months. At the stock Spectra Gear Ratio, the 231 has a very definite edge over the 260 prototype (first try at a 260) in smoothness and userfriendliness while at the same time has very good power as you can see in the IRCHA demo that HC flew, and the other John Garst Demo Flights in the HF video forum. We have said all along we would be honest about the 260 prototype, and this is what we have found to date. The 231 is very happy at the rev range of the Spectra is is a very smooth and potent powerplant for the G.

The other thing to consider with the TRM 231 is that Al designed the mod package to work in conjunction with the TRM tuned pipes that are in the works. :glasses2:

John please correct me if I am wrong about any of this. John IS the gasser heli expert behind TRM, and together he and Toxic Al, the Zen expert have done a very good job. They are both very conservative and have worked together very hard to bring the TRM 231 to production and availability through Miniature Aircraft.

[bigrcr]

Good Will. I will post more as I get time, got to go to work ....AGAIN!
The "stage 1 and stage 2 mods" are degrees of enhancement and performance if you will. I will delve into this further as I get time, bear with me.

Later!

[Sar]

Will, thanks for taking the time to type all of that out, the information is great and I am slowly building up a small spreadsheet on my available options to get as much info together as possible.

I am curious to see the availability of the TRM's as soon as the Spectra's start shipping again. 2-weeks seems to be kind of the running joke with MA according to the MA flyers at the field, but I hope my buds aren't too serious about that, I'm really looking forward to this build and strapping on a camera mount and getting to work.