amcross

My Feedback: (2)

One of my favorite common questions, so i figured i'd get it out of the way early....

The G2300 sets up a little differently from smaller or larger Tigres. (Please remember we are solely the US distributor. If you are outside the US, you may wish to contact the ST distributor in your region of the world, as your choices of fuel/plug, etc may affect its performance.)

First, the engine needs to be lean on top, as lean as you can possibly go without detonation.

Second, the engine needs to idle low...below 2500 and preferably in the 2000 or less range.

Third, the engine MUST be fed high quality high oil (18%+, at least partially castor) fuel. t will run on FAI fuel but prefers nitro in the 5-25% range.

This sport engine performs fabulously under these conditions for most sport pilots. It is a real powerhouse and work horse of a sport engine. However, this reasonably price sport-performance engine is not designed or able to perform for extended lengths of time in the 2500-4000 range. If you choose to ask it to do so, you must come back to idle prior to applying full throttle to clear the carburetor, *OR* supply the engine with significantly higher fuel delivery pressure by utilizing a high volume pump such as a *Varsane Perry VP30 Regulating Pump* while also using muffler pressure. (Please see note below on pump set up requirements.)

If the above steps do not resolve your concerns, then look to the muffler you are running. Fuel flow is a key concern of this engine, requiring good pressure to the fuel tank. In order to increase muffler pressure to the fuel tank, a twin exhaust outlet muffler needs to have the second stack partially or completely blocked. The same is true of exhaust systems made by other vendors, such as Bisson, or Slimline.

We've had excellent results using a SuperTigre "Silent Muffler" for the S-2000/2500, although it's a bit large, and doesn't hide at all well inside engine cowlings.

PUMP SET UP INSTRUCTIONS:
The pump should be adjusted to leave only a 1/32" gap.
keep the presure line as short as possible.
Set the pump first DO NOT set your carb and try to match the pump to the carb.
Use exhaust presure with the pump.

Sincerely,

Great Planes Model Distributors
[email protected]
www.greatplanes.com
www.bestrc.com
Phone: (217) 398-8970
Fax: (217) 398-7721

TOYMAKER

My Feedback: (6)

The ST2300 setup has been bounced off the wall many times. The only true way to cure the ills of this engine is to use the Perry pump/carb set up. Unless you can get adequete muffler pressure.
With a Macs quiet pipe (15cc) and a 17x10N APC w/OS "F" plug on 15% Ritches brew I get 8700rpm and dazzling vertical performance out of mine. I have a second one setup in a CAP with a Bisson muffler and 18x8 Simitar and it will turn 82-8300 rpms. A tuned pipe does make a difference.

I have two stock carbs for this engine if anyone needs one.

BTW I heard Super Tigre is back in production in the far EAST somewhere.... is that correct?

amcross

My Feedback: (2)

Hi Toymaker,
Yes, ST has moved and is up and running in its new location. The G90s are due in the states in the next 90 days with others to follow.

The ST 2300 performs great as what it is intended -- a large sport engine for the average pilot flying a giant cub, or warbird, or other bird where they are not critical on midrange and are not doing a lot of flying off full throttle.

With the perry pump on board, we've done fine with the stock carb WITH IT SETUP AS LISTED ABOVE. Works great!

Sincerely,
Mrs. AnnMarie Cross
Senior Manager, Proprietary Services and Support
Great Planes Model Distributors
[email protected]
www.greatplanes.com
www.bestrc.com
NO AUTORESPONDER

TOYMAKER

My Feedback: (6)

AnnMarie,

Your right for the sport stuff. We are just trying to make a pattern engine out of it. By the time you buy all the upgrades pump/carb you could get a pumped engine designed for the intended purpose. Live and learn.

Diablo-RCU

My Feedback: (1)

Hate to be disagreeable with AMC, but the stock ST carb is not OK. The problem is in the midrange metering which goes unusually rich. Look at the rotor slot on the carb and you will see a dogleg cut slot which makes the carb go very rich right off idle to 1/3rd throttle. A Conley carb (unpumped) does not have this problem and neither does the carb off the OS 1.08. The midrange richness problem is made much worse by any aftermarket muffler that results in low fuel tank pressure. Most people are using the ST with an aftermarket Pitts muffler....which has low tank pressure. A 9 or 10 mm venturi on the carb and a good metering system would solve these problems.

THE TAILBACKER

Frankly I think ST is going to have a rough comeback. There are alot of satisfied customers but also alot of dis-satisfied customers. This is one hobby where we have alot to choose from. There is something wrong with the carbs. Until they admit it, nothing will be done about it except buy a different brand. Explain to me why a fair amount of big cats run like crap. InstalL a Perry or OS carb and it is all of a sudden. Perfect. It is plain common sense. You have problems, don't waste your time fooling with it. Change the carb and be done with it.

flyathome

My Feedback: (7)

I have a ST2300 on which I am using the stock carb. It has proved to be very dependable, but only after I made several modifications. First, I took the carb apart and dremeled out the dog-leg. I kept the stock muffler, but plugged one outlet. Finally, I used an OS "F" type plug. I had mine on an Ultra Stik. It would fly for prolonged periods of time at 1/3 to 3/4 throttle and then transition to full throttle with no problems. It took me about three or four trips to the field to get it right, but after that I have been very satisfied with it. Its next home will be an Aeroworks 25% Edge.

amcross

My Feedback: (2)

Diablo,
We changed carbs, and were still not satisfied with the performance. Was it less noticable? yes. but still not what we wanted from the engine. We also modified the carb as described Again, better but not the level we felt the engine could be.

So we put the stock carb back on and pumped it as i described. And the engine is now fully capable of 3D level competitive flight. on the stock carb.

Is it unreasonable to think you should have to put a $50 pump on a $200 engine to make it give the same performance as a $500 YS? Not in my book....

Diablo-RCU

My Feedback: (1)

Hello again AMC:
I'm curious, which carbs did you try on the ST? I tried the stock carb, an ASP 1.08 carb, an OS carb from a 61-VF (with high low and midrange adjustment), the Conley Mega Pump carb with Conley regulating pump, and the Conley Mega carb (non-pumped version) without a pump. The best running engine with the most power was the Conley Mega carb non-pumped. The 61-VF carb ran fine, but power was down because of the small venturi.

I also seem to remember that the original instructions from GP on the motor advised people not to use ANY pump. Is my memory failing me? I tried 2 different Conley regulating pumps and had nothing but problems with excessive richness.

I'm sure my buddies at the flying field remember the Summer of ST2300.....where I spent mucho time doing carb experiments.

I still like the motor! Just wish it had a friendlier carb from the factory.

amcross

My Feedback: (2)

Hi Diablo!

We tried 7 or 8 different carbs. None gave us what we wanted.

Yes, the stock instructions were correct for any pump setup except one with excessive volume such as what we describe above.

Tuomo

I think these two mods cure 90% of the problems. The rest is covered by using some nitro in fuel -- FAI fuel is more critical. I did not have to do anything with carburettor.

Was it so that ST made a subtle change to carb at some point of the production? The other carb type is ok while the other needs the much discussed modification to the groove in carb slot.

Bob Pastorello

My Feedback: (198)

As one of the guys that came up the testing curve (see my web page) on the ST2300, there is NO doubt that carburetors WERE changed from the early run, increasing the dogleg in the barrel, which effectively WORSENED the richening as the barrel rotates up from the lower section of travel. That's where grinding the dogleg off came from. After that, I found the BEST overall performance to be with the OS Type F plug, and at least 20% nitro fuel, with good 18% oil. Pipe pressure had to be pretty high, or the high end would lean, no Doubt! I also had tried pumps, regulators, and other carbs, settling on the modification to the stock carb. Maybe the new versions, if/when they get going again, will consider the carb design as being fundamentally flawed, because it WAS....

amcross

My Feedback: (2)

Yes, the carbs changed from first production to later.

We did find that the particular pump combo listed above made it so we did not need to file out the dogleg, the motor could be set up and run as is, but only in such a high fuel pump pressure situation as described.

Diablo-RCU

My Feedback: (1)

Thanks Aerobob for reminding me!
You were kind enough to share info on the workings (or problems) of the Cline regulator with the stock carb with me too. I gave up on that combo after I learned that you were experiencing the exact same problems (going rich in outside anythings at part throttle). Pe Reivers in the Netherlands was also struggling during the same era. He wound up using a Walbro diaphragm pump on his.

The only dogleg rotor slot I've ever seen on any carb. What were they thinking?

Bob Pastorello

My Feedback: (198)

The REAL irony is that the earliest ST 2300's released had a straight groove in the barrel, and the P/N even matched the barrel for the ST 4500 carb! I know, because I bought a couple of barrels alone - they did NOT have the "dogleg"....Amazing that the later versions added it, because folks were cooking their motors by setting 'em lean (in reality, they were using muffler systems that did not provide adequate head pressure to the tank), so I *Guess* they figured "add more fuel", not bothering to analyze airflow through the venturi. But I'm no longer bitter; have moved on; now running MVVS 1.6 gasser (new today) and it is an awesome motor...

TOYMAKER

My Feedback: (6)

Hey AeroBob....

I have two of those thangs now... The only way I was able to realy make them run right was with the Perry pump/carb setups.
Once they where set I hardly ever touch the needle or idle.
MVVS gasser huhhh.. what plane do have planned for that engine?

Wayno.......................

Mike Bogh

My Feedback: (14)

BTT

OscarPilot

My Feedback: (7)

I have a 2300 on an Edge 540. I take my time with adjustments during break-in and run Byron Tigre Mix afterward. Never had any problems on any of my big cats (have 4) that weren't resolved after proper adjustment and fuel combinations... Fact is all but one of my engines are Tigres, and it is a gasser. I loved the Italian made but not sure I will even try the Chinese version. I looked at one in my LHS and was very disappointed with the alloy. Looks like cheap Chinese junk but still says "made in Italy" on the crankcase. Shame. shame, shame... The box did say made in China.

I guess I should count my blessings.

Bax

My Feedback: (11)

Oscarpilot,

Any G2300 in modelers hands was made in Italy. NO G2300's have been made available since the move. We'd not know about the "made in China" designation.

Your note didn't say what difficulties you're haveing with your SuperTigre G2300.

The G2300 is not intended to be run on any of the so-called "SuperTigre Fuels". It MUST be run on a blend that contains no less than 18% oil content. If you're running a low-oil fuel intended for the other large SuperTigre engines, then trouble will happen quite quickly.

We normally run regular 2-stroke fuel with 10% nitro. This has worked out well.

The first shipments of GS45's and G90's had many parts made in Italy. They were parts made by SuperTigre in Italy, and the engines were assembled in China. If the part said "Made in Italy", then it was so.

OscarPilot

My Feedback: (7)

Interesting Bill. Is the reason a higher oil content is recommended that the 2300 is a 90 with a 2500 piston and a shorter stroke thus having the same requirements as the smaller Tigres?

Could you reply to my previous post regarding removal of the drive washer on a 2000?

Thanks In Advance.

Oscar

OscarPilot

My Feedback: (7)

BTW Bax. The 2300 is just sweet, no problems of any kind.

Oscar