All,
I just Purchased a thundertiger .15GP for SCC. Its shaft size is odd 7/32 x 32?
I can not find a safety nut anywhere for this shaft size can ayone help?

Bill Turner at AB Products, email is [email protected]

great guy to do business with...

Let us know how it performs, I was thinking about buying that same engine.
Joe[8D]

Our Club has dove into combat head first we went from 1 club member having combat planes to over 20 within a month, most of the members have TT .15's and the reviews are awsome. The LHS did have some of these safety nuts that were modified from a different safety nut in a machine shop custom for the TT .15, but they are out .

Does anybody know a good source for the Blue MAS 8x3 prop used for SCC?

You can order the 8x3MAS prop from just about anywhere. tower carries them, as does most places that sell MAS props. The blue prop isn't any different from the black 8x3, and, in fact, they aren't makeing black 8x3s any more. But if you happen to find a black MAS 8x3, it is legal to use.

Make sure and balance the blue MAS 8x3s. I have not received one yet that was close to being balanced.

Cajun[8D]

its a good engine just hard to tune

Well I order a Thunder Tiger today cant wait to try it out on the GNAT im building!

I love the thunder tiger I ran 1 tank through it ritch then flew, adjustments were easy, I got a prop safety nut by tapping and drilling a smaller one

Well I don't have an awful lot of good to say about the Thunder Tiger .15. I have owned four of them and two I had to send back within the first two weeks due to a cylinder wall peeling and the other blew a rod bearing. Two of them would turn up to 17.5K with 20% nitro and the other two would barely make 17.0K regardless of what fuel you ran in it. But the worse thing wrong with them is the needle valve assembly is junk. The needle valve assembly comes in four parts, the needle valve two washers and a coupling for attaching the fuel tubing. There is no way that this thing will not spew fuel like a garden hose if you try to run it with a bladder tank. If you ever take it apart you will see that the whole assembly when screwed into the carb only catches on about two threads. If you try to put a little pressure on it to tighten it down it will quickly strip out. The aluminum washers will deform the first time it is tighten it down and you will never get them back in the exact same position if you ever dissemble it. The only way that I can keep them from leaking fuel/sucking air is to slather about 1/8th inch of GOOP around the whole assembly and replace the GOOP about every second time that you take it flying. My advice is to save yourself a lot of grief and get rid of the Thunder Tigers and get anything else, preferably OS LA.

I just got some TT .15's and I am a bit worried about the needle valve like you said! It looks to be pretty easy to change to a RNV operation though. I'm not going to run bladders so maybe it will be ok. I do like the metal backplate and the carb attachment area looks real strong. I haven't run any yet. I hope I have better luck taht you did!

The thunder tiger 15 ( new series in red box ) is a good sport motor that does not need to be run on a bladder. Runs fine as is. With a few modifications this motor will perform as well as any 15 with a muffler attached and will last longer. As with all motors there is a weak point . If you try and turn over the motor in a flooded condition you risk breaking the crankshaft. Liquid will not compress. I have tested this motor with different props, fuels, intake timing, and compression ratios. No abnormal wear was noted untill the rpms exceeded 23000 rpm. Even then only minor wear on the crankshaft bushing was found. This condition however allowed the motor to run even better. Make sure you run castor oil / syn with at least 18% oil content. The most effective way to increase power without taking the motor apart is to open the carb to .205". This alone increases the rpm 1000 rpm. Removing the baffle and opening the muffler to .250 will yield another 500 rpm but you loose the back presssure needed for a constant run. This however can be overcome by modifing the internals and increasing the rpm another 2500 rpm.

One thing you need to keep in mind when talking about the TT engine is that most guys are talking about using it in SSC class combat. In SSC, boring out the carb is not legal, and therefore talking about the power produced with that mod doesn't help. Same with internal mods to porting and whatnot.

Removing the baffle is ok, but i'm not actually sure about boring out the stinger, I think that's an open question.

Are you using TT's in competition? If so, what kind of RPM are you getting with it on the SSC prop and in an SSC legal configuration?

7100 RPM in SCC 8x3 no mods

I assume you meant 17,100rpm, not 7,100

What fuel, and what air temp/humidity? (approximate number for the weather is fine)

55deg F 15% wildcat humidity 50%

yes 17,100

Don`t know what the rules allow. Is there a max carb size? If not ,the motor with the largest carb most likely would be the strongest.

MyWay,

There are two carb restrictions in the SSC rules. First you must run the carburetor that the manufacturer supplies with the engine. Second you cannot modify the carburetor in any way which precludes drilling it out. Now on to your observation abour performance and carb throat dimension -

The engine with the biggest bore will have the most performance if a couple of criteria are met:
1. The fuel system is able to supply all the fuel that the engine can take - a pressure bladder is necessary with large bores
2. The timing of the engine is such that it can get the fuel volume in and out of the combustion chamber

The larger the carb bore (generally) the less vacuum is created for fuel draw, hence the need for a pressure feed system. Tuned exhaust are not legal in SSC but in Open A a tuned mousse can exhaust system will help get more fuel and burned fuel out of the engine. These two changes are likely to have more impact than the throat diameter of the carburetor. Just my $.02 worth.

Can you explain pressure bladder I run an OS 1.60 with a Perry V-30 pump is this the same thing?

Check out www.texascombat.com for great info on bladders and pressure.

The bladder pressure is a power booster in hard turns and high G maneuvers. It minimizes speed bleed-off. But it is a pain in the rear to run until your comfortable with it. Bladder tanks and one way check valves in the muffler pressure line are good alternatives for a smaller boost in fuel pressure.

Cajun[8D]

dntmn, how many of your 20 pilots will be flying in Paris next month. It should be the largest attended R/C combat meet in the world[X(]. Hope to see you all there.

Cajun[8D]

All sport engines come with VERY conservative timing and head clearance numbers.They also don't breath as well as they should. Most of the time you can drill the intake at least 1/64 to 1/32 more without having to do internal mods to get the extra R's.The extra RPM's WILL show up on a ground tach test so don't do it if you are getting close to max already. If you can't get to 17500 at all, I would do what ever mods you have to do to get it there or your SSC plane wont fly well.

Cajun,
I am not sure, our club just got into the SCC combat thing, I don't believe we have any pilots that have ever competed in an organized competition. Last Sunday we had a Combat Day at our Field and around 12 pilots flew SCC style planes, We did not organize it or use honey on the wings we just tied on ribbons and tries to get prop cuts, we had as many as 8 planes in the air at once. We placed a notice in our newsletter aboul your event, I do not know how many pilots will attend. If a lot of pilots fly SCC this Sunday we may consider having an santioned combat event ourselves, the only problem is that no clubmembers or CD have enough Practical Combat experience to effectivly CD an event, we will have to see how it goes. I CD our Annual IMAC, but don't have a clue on CDing a Combat event. I have heard a lot of good things about your event. I didn't score any cuts last weekend, but I was having a blast going for altitude then when the other pilots would get in a bunch, I would Dive through the middle of them and hear, what the ")*&^(*&" was that. Lots of fun

Dan Powell
TRC President

Dan, if you wish to hold a sanctioned SSC event in Greenville, coordinate the dates with the NTRR events and I will CD it for you. Your in a great location close to a bunch of combat guys. The DFW/NT area probably has more dedicated combat guys than the rest of the country combined

Tell your guys not to worry about a lot of experience. They will have a blast at Paris, especially on Sunday in SSC. You don't need to win in combat to have a blast. If I can just get a cut or two on one of the top dawgs, and have fun doing it, I've had a great day.

My goal in Paris is to kick Lou Melancon's butt for comparing Texans to Yankees. I'm sure lots of the Texas pilots will have him in their sites. Since he doesn't fly much better than I, or your new pilots for that matter, he's probably going to be in a heap of trouble in Paris.[>:]

Cajun[8D]

Cajun
Our club is actually in Sherman, I live in Gainesville. Sounds like your event will be a lot of fun.