ST parts ID help

[Steve_Pollock]

I have two NIP ST heads.  One is marked 1341, fits into about a 20.5mm cylinder bore, head bolt spacing diameter about 29mm across the head, and it has a cut for a baffle.  May be a G21/40 head.  The other is marked 1550, fits into about a 20mm cylinder bore, head bolt spacing diameter is also about 29mm, and does NOT have a baffle slot.  May be a G21/35 combat head.  These part numbers are earlier than my reference material.  Since they are in original packaging I did not remove them to make exact measurements.  Thank you in advance for your help.

[Phil Spillman]

 ST had a plain bearing .35 billed as a Stunt Engine back in the 70's and 80's. It was also sold as an RC engine both varieties had plain bearings, not ball bearings. The Carrier community had a rule for awhile that only PB engines would be eligible for Profile Planes. after I bought one of these engines they changed their rules so my engine wasn't quite as good as I had wanted it to be! This engine did have a baffled piston and so your grooved head could be for this variety of the "C" PB group. They also had a Schneurle PB design which was great for Combat, Slo Rat, and Sport flying in general. This model didn't have a baffled piston as it wasn't needed! These were really fine running machines.

I've sold off or given away most if not all of my older ST's save for the vaunted G-21 .46's which still make a fine running Stunt engine!

Hope these ramblings were of some help to you!

Phil Spillman

[Steve_Pollock]

Thank you, Phil -- it does help.  I just don't have a parts list for the ST .35 combat and ST .35 stunt engines.  I have a bunch of parts, including ST parts, that I'm getting ready to sell, but I'd like to know what engines they fit before I list them.  The fact that Supertigre changed parts numbering systems several times doesn't help. either!

[Roger Vizioli]

Steve,
check your e-mail.

Roger Vizioli

[Bob Matiska]

My 1968 World Engines catalog doesn't list either part number. The 1974-75 edition, however,  shows part number 1550 as the head for both the G21/35 ball bearing engine and the plain bearing 35 Combat. The number 1341 doesn't come up in either catalog. An engine test of the G21/40 RC at Sceptre Flight lists the bore of that engine at 20.4 mm, so the 1341 head is indeed most likely from an ST 40.

Good luck,

Bob in NEPA