Thunder Tiger GP 42

[George Mitchell]

This is the one that has two bolts on top to mount the carb.
Did Thunder Tiger make a bolt on venturi or must the case
be mutilated and drilled through. Thanks.

[Steve Helmick]

You really should email Leonard Neuman. Supposed to be pretty nice engines, but a PITA to change over to a venturi. AFAIK, there is no TT factory conversion. You might also try emailing the guy at TT in Taiwan...Sum Ting Wong.  Steve

[dennis lipsett]

Having done about 5 of these I wouldn't say that it's much trouble to convert it to a venturi and nva.
Leonard sells the venturi which has a slight taper to match the engine and you clamp your motor by the engine lug,hold the venturi tight into the case and drill the hole for the nva through the case and venturi at the same time. Install the nva and your good to go. No, you don't have to dis assemble the engine, at least I don't. A little piece of paper towel into the case and your good to go..
How does it run, Well you won't want to go back to your OS 40 FP or the LA 40. It's usually a 1 flip starter for me and very consistant runs. I like mine and highly recommend them to others.
dennis

[Chucky]

About a year ago, I picked up a pair of lightly used GP 42's at an R/C buddy's "gettin' out of the hobby" garage sale for $10 each.  Installed Leonard's black delrin venturi with OS NVA in one of 'em as Dennis describes.  I used a drill press and machine vise as Leonard recommended, otherwise same technique, including paper towel in the crank case to keep the shaving out -- no tear down required.  Findings at the field are in line with what Dennis describes.  Liked it so much, I converted the other one as well.  Am running Leonard's CNC tongue muffler on both.  Excellent power for a .40 motor.

[Scott B. Riese]

don't tell anyone but it's really a .39 when you mich it out..........