ST .46 Ring Replacement

[Roger Altizer]

Gentlemen,
I have a good ST .46 that needs the ring replaced and I would like to have it "Stunt Tuned".  Who could you recommend do this for me?
Thanks,
Roger Altizer
AMA 17351

[Brett Buck]

Gentlemen,
I have a good ST .46 that needs the ring replaced and I would like to have it "Stunt Tuned".  Who could you recommend do this for me?

   I don't have a recommendation on who, Randy would probably be my first call. DO NOT have it "stunt tuned", it's stunt tuned already, it does not need modifications to work as well as it can for stunt purposes.

    Brett

[Roger Altizer]

Thanks, Brett, it has been a good engine that I use for OTS, but has become very hard to start after being so reliable the past 5 years.  From what I understand, hard to start is a sign of a worn out ring.  I thought maybe I could wring a little more power out of it by having it "tuned", so to speak.  It can't hold a candle to my schnurle ported Fox .45's or my OS .46 LA's, but it was great in my OTS Humongous.  I'll probably just install a new ring myself.  Can anyone tell me what the gap should be?

Thanks,
Roger Altizer
AMA 17351

[Brett Buck]

Thanks, Brett, it has been a good engine that I use for OTS, but has become very hard to start after being so reliable the past 5 years.  From what I understand, hard to start is a sign of a worn out ring.  I thought maybe I could wring a little more power out of it by having it "tuned", so to speak.  It can't hold a candle to my schnurle ported Fox .45's or my OS .46 LA's, but it was great in my OTS Humongous.  I'll probably just install a new ring myself.  Can anyone tell me what the gap should be?\

  Those are definitely signs of a worn-out ring. But most of the "stunt mods" done on ST46 was "to soften it up" which is *absolutely the last thing you want to do to it*. Get a good ring (which may prove problematic...) rough up the liner if necessary, and if it still doesn't put out enough power, add nitro.

  The most powerful ST46 we ever had around here was mine, *straight out of box*, with a good factory ring.

 .002 is a typical ring gap, tighter the better within reason.

   Brett

[Dan McEntee]

    I had a ST.46 in a SIG Chipmunk years ago. Was putting in practice flights ahead of the SIG contest. Put up my 2nd or 3rd flight of the day, and when my turn came around again, it would not start. tried all the usual stuff, and nothing. Gary Hajek said the ring just got fully worn out. He had a new one, so got it from him and proceeded to call Tom Lay to get the skinny on changing the ring. I had done ring jobs on motorcycle and kart engines before, but had heard tigers were tricky. Tom said to send it to him, but no time for that, so he coached me on how to disassemble it. Lots of these have been ruined either taking them apart or putting them back together, like one I had that had cracks and vice jaw marks on the bottom of the case from the previous owner using that to push the liner back in! It is tricky to get apart if it has a lot of time and castor crud built up in it. The liner has to be out to remove the wrist pin, and those are the two sticklers. The liner is a slight shrink fit int the cylinder the wrist pin has to come out through the hole in the case, I successfully got mine apart after a while. Tom told me .001" for ring gap but no more than .002". As mentioned, rough up the bore and check for anything that may catch the ring. Careful break in and you should be good to go. But, if you have never done a ST.46 or .60 ring, and have the time, send it off to Randy. I don't know of anyone else that does Tigers since Tom passed. I understand your passion for it Nothing sounds like a Super Tigre!  There may be better engines for modern competition, but none sound like those beauties. The closest thing is their G-51, and I have put in lots and lots of laps with those, but have yet to wear out a ring. Good luck with it!
  Type at you later,
   Dan McEntee

[M Spencer]

tres an oiticle ere , on toonin the Tigres . Liberated Via P A M P A I believe . Perhaps . Getcha the ring gap anyway .

http://www.clamf.aerosports.net.au/newsletters/ACLN/Issue39.pdf

THAT SAID , I believe the Tight Fit of the Bearings generally on Super Tigres is part of the design philosopy .
A heat gun seems vastly superior to other methods or bearing / sleeve  removal / fitment .

A machined dowel helps with the bearings , but some people have been known to use the crankshaft .

The Wrist Pin is the biggest #!*^ , to free / remove .
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The velly erry Tigres had the biiger Hemi Chamber narrower squish band , for a ' Hemi ' conversion , or copy . If you must .
The Dual Ring narrow bypass ' big chamber ' head  Tigre .46 .



Series Two ( Dual Ring ) ST ' V ' 60 hasa the bigga chamber head a there .
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Parrently there TWO ST Part Numbers for RINGS . as there were CHROME & later Non Chromed LINERS ,
one could be ? right in assuming that this relates to that ! .

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If ya can strip it down & clean it all , It may just be gummed up in the Gudgeon ( wrist pin ) which they say'll do that ( go gutless )
If yr carefull you WILL NOT break the RING . get it moving freely / rotateing with C.R.C. first .

Gently walk it off with thumb nails or a scalple blade . then CLEAN THE RING LAND .

Measuered a well used G 51 & it was sttill 5 1/2 thou. ring gap . So I guess if youve got 4 thou. your fine .

Youll find info /' debates ' in search in engine stuff here .

My From New 21/46 will swing a 12 x 5 & pull 65 Oz satisfactorally . Slow . the Mewgull High A/R sucker , at 70 ft. lines . .018 even .
5.5 laps. But its notta wind ship .Gotta Std. type intake @ .210 though .

Nuther trick from the unided states issa drill the spray bar , both ways , 1.5 m.m. , for better kneedling . ( outlet & bore )

SO its the strip , inspect , clean ( & polish if your that way inclined ) & handle with care .

Screwdrivers ! , 4th grade engineering was making things like that . If ye dinnae have one ta fit , Grind a CUSTOM blade , Flattish Taper ,
Exact Fit to slot & same width as screw head !

Dah . 

[Lyle Spiegel]

is this supplier produce same ST46 rings as previously sold by Frank Bowmen? Has anyone been installing them?   
https://rmjmachineworx.com

[RandySmith]

You need  to be  careful  what you do to this  engine,
I have  most all parts for it including  bearings  rings GOOD rings...  Cranks  pistons sleeves  etc...
The end gap will very for  chromed  or  just steel sleeves
You cannot  just install the  ring, You need  to clean it up and the  sleeve  needs to be   lightly honed or  else the new ring will  never seat correctly.
While its  apart  it should have  new bearings  if its had a  good bit of run time

IF you take it apart  please be careful  trying  to remove the  pressed in sleeve,  I cannot tell you how many  I have had sent to me  with  plier marks on the  top of the  sleeve  RUINING the sleeve, there are several pitfalls in working  on this  motor

Randy  678 407 9376