Author Topic: Super Tigre G60 Blue Head (Read 8501 times)

Joshua Harel · « **on:** November 18, 2011, 04:40:49 PM »

I have a ST G60 Blue Head RC engine. This engine is a ringed, flat top piston - non schnuerel. Has anyone had experience converting same to a stunt engine?
Thanks
Joshua

RandySmith · « **Reply #1 on:** November 18, 2011, 06:48:44 PM »

Quote from: Joshua Harel on November 18, 2011, 04:40:49 PM

I have a ST G60 Blue Head RC engine. This engine is a ringed, flat top piston - non schnuerel. Has anyone had experience converting same to a stunt engine?
Thanks
Joshua

Hi The single piece case V 60 is the one to get, The G-60 is very heavy and timed more for RC

Randy

Mike Greb · « **Reply #2 on:** November 19, 2011, 10:54:44 AM »

One of our local engine experts had a non-bluehead Tiger G60 and it ran quite well, but it was on a airplane designed for heavier engines. Also, I don't know if he did anything to the internals, he has passed away so there is no way of finding out now..
One problem with the supertiger line of engines is that over the years supertiger would slightly modify the motors over the different production runs.

David Zwolak · « **Reply #3 on:** November 20, 2011, 07:45:17 AM »

A number of years ago when he was still alive, GMA himself mentioned to me that he had seen a G60 fly well with a "stunt run". George stated the trick was to reduce the compression with head gaskets. Based on GMA's comments, I thought it would be interesting to try a G60...

Granted, the G60 is heavier than the ST60. But, if you check the old Peter Chinn engine reviews the ST60 and G60 share similar timing numbers. Not exact - but close.

No guarentees here. Just a bit more info for this thread.

Joshua Harel · « **Reply #4 on:** November 20, 2011, 07:55:35 AM »

A heart felt Thank You to all who replied thus far, I truly appreciate your comments and advice.
Joshua

Air Ministry . · « **Reply #5 on:** November 21, 2011, 07:45:27 PM »

Been a few enquieries here before . Good nfor semi scale. Saves nose Wt .

seen r.c. saying two 14 x 6 for four blade in P-47.Has a bit of torque .

Two or free renouned types think they give a good stunt run .

Whadareya building for it ??

Joshua Harel · « **Reply #6 on:** November 21, 2011, 08:09:06 PM »

Don't take it wrong everyone, I just don't understand why so many are getting a kunipsch over an ounce or so more on the engine when it comes to stunt? I am not planning to use this (or any other engine for that matter) in the NATs, I am just a sport flyer getting back into CL after 33 years hiatus. So, my question again: other than it being an ounce heavier than the stunt 60, can it make a good stunt engine for sport flying?
Thanks
Joshua

rustler · « **Reply #7 on:** November 22, 2011, 01:34:44 PM »

Just make your nose length accordingly.

One thing I have not investigated so far - GMA taught us that for a good 2/4 run you need a fairly low blow-down figure, - about 7deg. is good?
The ST porting is virtually simultaneous, so it should meet the stunt requirements. Yet this ST timing is used very successfully in their racing engines. Anyone know if they also give a nice 2/4 stunt run?

RandySmith · « **Reply #8 on:** November 22, 2011, 02:03:25 PM »

Quote from: David Zwolak on November 20, 2011, 07:45:17 AM

A number of years ago when he was still alive, GMA himself mentioned to me that he had seen a G60 fly well with a "stunt run". George stated the trick was to reduce the compression with head gaskets. Based on GMA's comments, I thought it would be interesting to try a G60...

Granted, the G60 is heavier than the ST60. But, if you check the old Peter Chinn engine reviews the ST60 and G60 share similar timing numbers. Not exact - but close.

No guarentees here. Just a bit more info for this thread.

Not really, The old aluminum colored head G-60 shared timing near the Sleeve timing of the ST V 60, The problem is they made many models after that and the one that he has is a Blue head version that is a knock off of Loop Charged ported with a flat top piston, this is a way to try to get around the loop charge porting patent. and the inside being very much more open gave a lot differant motor run, and a lot more power from these models

Randy

Steve Helmick · « **Reply #9 on:** November 22, 2011, 03:11:21 PM »

Quote from: Joshua Harel on November 21, 2011, 08:09:06 PM

Don't take it wrong everyone, I just don't understand why so many are getting a kunipsch over an ounce or so more on the engine when it comes to stunt? I am not planning to use this (or any other engine for that matter) in the NATs, I am just a sport flyer getting back into CL after 33 years hiatus. So, my question again: other than it being an ounce heavier than the stunt 60, can it make a good stunt engine for sport flying?
Thanks
Joshua

If you check the weights to the ST .60 and ST G.61, you'll find that the difference is more like 6 oz (19-ish oz vs. 13-ish). Seems like a lot to me, but might be just the thing for a round engined semi-scale model, too.

Given that the thing runs steady and makes decent torque, you can always fall back (or forward!) to a 2-2-2 run and skip the 4-cycling nonsense...just run around 4" to 4.5" pitch...and enjoy much better fuel economy. It might not be what you remember from our youth, but your airplane will probably like it much better.

Steve

RandySmith · « **Reply #10 on:** November 22, 2011, 09:09:15 PM »

Quote from: Joshua Harel on November 20, 2011, 07:55:35 AM

A heart felt Thank You to all who replied thus far, I truly appreciate your comments and advice.
Joshua

Hi Joshua

When I said very heavy, I didn;t mean an ounce, the Blue Head is much more weight than the other 60, You can put a 18 or 20 ounce engine on a plane you will just need to have enough wing to carry the weight and adjust the nose/tail moment to balance the plane

Regards
Randy

Joshua Harel · « **Reply #11 on:** November 23, 2011, 04:46:02 AM »

Bob Zambelli and I compared the weigh of the ST V56 and the G60 BH yesterday. Both were without a muffler, the 56 had no carburetor and the BH had the RC carburetor on it. The weight difference was 2.5 ounces.
Joshua

RandySmith · « **Reply #12 on:** November 23, 2011, 08:37:00 AM »

Like I said above you can run the heavy motor, you will just need to get the balance right, So use it and let us know how the BH runs for you. I would look for a lighter muffler for the BH than the one ST made for it, remember you will have to balance the excessive nose weight with adding tail weight to the plane.

Does your BH have a Brass or steel sleeve in it?

Regards
Randy

Joshua Harel · « **Reply #13 on:** November 23, 2011, 09:55:28 AM »

Randy
The engine has a flat top piston and appears to have a chrome plated cylinder. I am not 100% sure though because I did not take the head off. Do you have head shims for it? Also, I need an NVA. Bob has kindly volunteered to machine a venturi and we plan on running it very soo. I will report back what we find.

RandySmith · « **Reply #14 on:** November 23, 2011, 12:46:22 PM »

Quote from: Joshua Harel on November 23, 2011, 09:55:28 AM

Randy
The engine has a flat top piston and appears to have a chrome plated cylinder. I am not 100% sure though because I did not take the head off. Do you have head shims for it? Also, I need an NVA. Bob has kindly volunteered to machine a venturi and we plan on running it very soo. I will report back what we find.

Yes the Enya 45 NVA will work as will the Mid sized ST NVA, I do not have a muffler that is not stock and about 6 ounces so You may want to try the MACs one. I do still have a few side to rear headers for this engine,
Regards
Randy

Jim Kraft · « **Reply #15 on:** November 23, 2011, 02:48:16 PM »

I flew one in R/C pattern for 15 years, and they do have a chrome sleeve. It was a good steady runner and I never did wear it out. If I remember right it did not like to 4 cycle, so I would use a flat pitch prop, and run it in a wet two stroke. They do like to turn up pretty fast.

Air Ministry . · « **Reply #16 on:** November 24, 2011, 05:33:14 PM »

Sounds like its the ABC motor , with the high out put .
Ringed blue heads are baffled piston .

They claimed 2 hp @ 16.000 for the ABC , better than most schneurles at the time .

Not to say it wouldnt work o.k. with a few head gaskets and a small intake for stunt .
Maybe a V small intake . The 21/35s with the 1/8 bore intake swing a 10 x 6 3 blade dead steady ,
unmuffled at least .

Joshua Harel · « **Reply #17 on:** November 24, 2011, 06:09:42 PM »

This may be a little unusual but the engine definitely has a Ringed Flat (as in NO-Baffle) piston.
Joshua

Joshua Harel · « **Reply #18 on:** December 06, 2011, 07:02:50 PM »

The conversion is complete - thanks Bob for the beautifully machined venturi, and, based on Randy Smith's advice an Enya midsize NVA was installed. We tested the engine on the bench and with a 13-6 prop it was notably smooth running and powerful. The engine does need full break in now to set the ring. Weight without the MAC 6900 muffler is 15.8 oz, the muffler added 2.6 oz. We plan to install the engine in a large model and fly it sometime after Xmas.
Joshua

Joshua Harel · « **Reply #19 on:** December 06, 2011, 07:04:29 PM »

Here's another shot.

David Zwolak · « **Reply #20 on:** December 08, 2011, 06:35:08 PM »

Joshua - Real nice. I am interested to hear how the G60 performs. Especially with the MACS muffler. I run a MACS on my LA40 to good effect. Keep us posted please.

Joshua Harel · « **Reply #21 on:** December 08, 2011, 07:39:02 PM »

I ran the engine today on the test stand. Altogether about 45 oz. of fuel through it. The engine fires on the first or second flip, I used a 14-4 prop and running slightly rich tached it at 8700 rpm. Noteworthy was the smoothness and steadiness of the run. The engine never missed a bit and was very smooth running. The MAC muffler is a real winner. I am very sensitive to noise and the muffler cut the high shrill and produced a rather nice, throaty sound. So far - I am very favorably impressed with what I see. The ring started setting and compression went high to where it is fairly difficult to turn the engine by the prop driver against compression.
Joshua

proparc · « **Reply #22 on:** December 08, 2011, 08:26:49 PM »

Screw the weight!! You Sir, have hit the Jackpot. I personally, will be eagerly awaiting the build thread commensurate of a motor of this caliber.

Russell Bond · « **Reply #23 on:** December 11, 2011, 06:09:19 AM »

I had one of these in 1979.
I bought it by mistake. (Instead of the V60.)
It has Perry porting and I remember it pulled around a 740 square, 75oz stunter with ease.

Joshua Harel · « **Reply #24 on:** December 11, 2011, 06:56:20 AM »

Russell

I am curious, do you recall if the difference in engine weight indeed made any noticable difference in the performance of the plane? What plane was it?

Joshua

Russell Bond · « **Reply #25 on:** December 11, 2011, 02:07:32 PM »

Haha, too long ago to remember.
All I know is it did seem to work ok, but I sold it and bought the correct one as it was lighter.
The plane was an own design.

Joshua Harel · « **Reply #26 on:** January 05, 2012, 06:45:01 PM »

We are going to install the engine in a Polaris and fly it tomorrow. I will take pictures and provide a flight report. Stay tuned.

Joshua

Joshua Harel · « **Reply #27 on:** January 06, 2012, 03:12:40 PM »

It flew GREAT:)
Bob installed the engine in an old (though beautifully built) Polaris, weighing approx. 80 ozs. 13-6 prop, 10-22 Power Master fuel and 65' wires. My obsevations:
1. Engine starts on 1st or 2nd flip.
2. Very smooth and near vibration free running.
3. Very powerfull, consistent run throughout the entire flight.
4. Airplane really pulls - Wowha!
Bob, if you read this, would you please chime in with your observations?
Joshua

Joshua Harel · « **Reply #28 on:** January 06, 2012, 03:17:46 PM »

Here are a few pictures:

Robert Zambelli · « **Reply #29 on:** January 06, 2012, 06:57:47 PM »

Adding to Josh's comments, I was quite impressed by the performance and running characteristics of the Blue Head ST 60.
While it did make the plane nose heavy and a bit sluggish, that can be easily trimmed out.
We should also note that this engine produces a somewhat different run than the small-case version, pretty much a constant speed throughout the flight. Keeping in mind that it has a flat-top piston and is either Perry or Schnurle ported, some rework might be required to obtain a classic 2-4-2 run.
I may have a spare head around and if I do, I will modify it by enlarging the combustion chamber radius and narrowing the squish band.
Josh was not kidding about smoothness - it was about as vibration free as anyone could ask for.
To be noted: It is THIRSTY! I left in the three ounce tank that I used when testing the ENYA 53 4 stroke and it just wasn't enough to do much. I suggested that Josh install the largest tank he can fit.

More to come.

Bob Z.

Jim Kraft · « **Reply #30 on:** January 13, 2012, 04:34:38 PM »

I am guessing that one is Perry Ported. The one I had was ringed with a baffle piston. I still have a spare head and it has the slot for the baffle. I don't think any of the Blue Head 60's were schnurle ported. That came later in the X-61 if I remember right.

Joshua Harel · « **Reply #31 on:** January 13, 2012, 04:38:49 PM »

Jim

Do you still own the engine or only have the spare cylinder head? Bob is looking for a head he wants to modify to get a 2-4 run.

Joshua

Joshua Harel · « **Reply #32 on:** January 20, 2012, 04:33:16 PM »

I ran some props on the Blue Head yesterday in my shop. The engine was mounted on a test stand'
Top Flite 13-5 9,700 rpm
Zinger 13-6 8,700 rpm
Top Flite 14-4 9,100 rpm
Top Flite 14-6 7,700 rpm

Joshua

Jim Kraft · « **Reply #33 on:** January 20, 2012, 06:41:45 PM »

Yes Joshua; I sold the engine long ago, but still have the spare head. It does have the slot for the baffle, but if you think it will work, it is yours. Just e-mail me with the address to send it to if you want it.

Joshua Harel · « **Reply #34 on:** January 20, 2012, 07:00:49 PM »

THanks a bunch Jim. I sent you an email with my address.
Joshua

Jim Kraft · « **Reply #35 on:** January 21, 2012, 11:44:47 AM »

Got it in the mail this morning Joshua. Hopefully you will be able to machine out most of the baffle slot, although it probably would not make any difference anyway. Otherwise I think it should be the same as the head you have on yours. Let us know how it works out.