Strato Bug 304-A Cylinder

The one Strato Bug I bought from an estate of an older gentleman looked like it was never apart. But who knows what happened in those 60 years!

It has the later flanged crankcase and the large dia head. It has two bypass ports in the cylinder.

The first one I bought was fake. Gotta look at the backplate and the tank in the inside to see how it was made. From the outside you cant tell a real from fake.

Thanks Jason. Just what I was looking for: Someone with a flanged case and big head Strato Bug like mine that comes with a bit of provenance so that you might think it's untampered with. Dual bypass it is. Thanks to all of you and especially for making me feel welcome to the forum.

Now if someone can point me to a Tee Dee .09 in the orange bubble pack they're willing to part with.....

Did the Strato Bug Cylinder have sub piston induction? I went through the other threads, and I didn't see that it was mentioned. Is that because it didn't have SPI? Thanks. Andy

I often refer to the Cox Model Engine Handbook as it seems to me to be the best reference available.
I found this statement on page 11 regarding cylinder markings and it relates to the Strato Bug cylinder
question.

"P-40 - This was the first cylinder that Cox marked.
Although the P-40 cylinder was used in the P-40 model,
it signified that it was the first engine in which the glow
head thread size was changed. After all of the old size
glow head cylinders were used, the stamping of P-40
on the cylinder was discontinued."

This would seem to imply that if a Strato Bug was produced with the large diameter head
it would have had a cylinder with the P-40 stamping.

As for the lip on the rear of the crankcase I have never had any luck finding out when, why, or on
what these cases were used. The CMEH only mentions it briefly as a variation of the Space Bug
on page 39.

Another part to consider is the piston. The Strato Bug should have the pre 1957 three piece piston
with alloy connecting rod.

Sounds wacky to me that the 1959 P-40 Super Bee was the first large diameter thread engine. Weren't there lots of big head engines after 1955 and well before the P-40? I'd swear I have some. And didn't production of the Strato cease around 1955, well before the 1959 P-40? Well, I guess anything is possible.

Has there been a discussion on the little marking found inside the cast crankcases. I've seen them on all the bugs and the Thermal Hopper. Could it indicate the production run or perhaps the casting set used to produce the engine? Might they tie in to what could be valuable chronology?

A fun discussion. Thanks everyone.

I've never seen the mark inside the early cast case you mentioned. I'll have to check some
of mine to see what they have.

Definitely a fun topic but one I'm afraid may never lead to a solid conclusion.
I do believe much in the CMEH is accurate and admire the authors efforts (and
I dream about Dan Sitters Cox engine collection!) but there are areas that leave
me wondering and this is one of them. Same goes for the popular Cox reference websites.

The statement struck me as a bit wacky too, that the P-40 cylinders were only used to mark
the first large diameter cylinders because supposedly the P-40 airplane did not appear
until 1959 and the Strato Bug was produced until 1956 while the TD-3 and TD-4 airplanes
were produced from 1954-58 and 1956-59 respectively. During that time were there TD-3's
and 4's produced with Babe Bee's having small diameter single bypass cylinders?


I'm wondering if it is all just a confusing mix of manufacturing dates getting mixed up
with dates models hit the market or were removed from the market. When you consider
that a model would be in production long before it actually hit store shelves it kind of
makes sense that when a lot of production changes are happening around the same
time the history gets hard to sort out. Would also serve to explain the P-40 marking,
that perhaps the mark targeted those cylinders for the P-40 the manufacturing of which
must have started well before its 1959 release date.

I really have no idea. Researching old magazine advertisements would might help
sort it all out but a good mag collection is something I only wish I had.

I have copies of MAN from late 40's to 90's.

I can take a look around the '58-59 issues

I remember reading that as well...someplace...and I almost got to wonder if Tim Dannels might of got it confused with the Comet P-40 as that was the first model to use the new Comet/Cub engines with the new glowhead (same diameter as the '56 Babe Bee) instead of the smaller diameter head/glowplug...again same diameter as pre '56 Cox glowheads. That's almost too much of a coincidence?

I don't think there where any small head Babe Bees manufactured, that seems 180 from what I've read about Leroy Cox and Co., that they would deplete supplies before moving on? However that may be a perfect world scenario, I think they used up the last of the small diameter head/cylinder on the Space Bug and SBJ.

The flange was added to the cast case in early '54.
Production of the Babe Bee was Jan of '56
I think production of Strato Bug was '55 only.

Heres what I posted on my web site years ago, I think I got the info from Mud?:
The reason the cylinder was stamped “P-40” was so machining and assembly line folks could differentiate between it and the Space Hopper cylinder. Both cylinders looked identical. However, the P-40 cylinder had a straight bore, whereas the Space Hopper was tapered. It was also the first new production engine to use only the new style (large dia.) glowhead and after all the old style cylinders (small dia. glowhead) were gone. In 1961, Cox began a numbering system for the various cylinders already.

Hopefully we can summon the great Mudhen to clear this up!

Here's Mud's reply:
In the late 1950’s, all .049 product engines were single ported…until the P-40 Flying Tiger. Unfortunately, all .049 product engine cylinders looked identical.
The P-40 stamp was only used to distinguish the “Super Bee .049” product cylinder from other .049 product cylinders and to avoid having Water Wizards, Super Cubs and TD-3’s leave the factory with a twin-ported cylinder intended for the new Flying Tiger. The new “Super Bee” engine was only available in the P-40 model.

More info from Mud:
Dan's info on the P-40 stamp is wrong. The larger cylinder and head was released 17, Feb. 1955. (Blueprint # A302-A1, a copy of which I have.) Formal identification number stamps began in May, 1961 (based on the original Engineering Change Letter, which I also have.) So, according to Dan, ALL .049 cylinders manufactured between Feb 1955 and May 1961 would have been marked, 'P-40.' But that's not what we see. (In fact if Dan were correct, then we should see thousands of 'P-40' stamped cylinders.) What we do see is Cox releasing the New P-40 Flying Tiger with the new Super Bee .049; a twin-ported product engine found in a product. (go figure.) The early Space Hoppers had, (I think,) a tapered cylinder. So to differentiate between it and the P-40 cylinder makes sense. But, in short, the Super Bee .049 was the first twin ported product engine. And, at the time, the only twin-ported product engine. It needed an identification mark of some kind to avoid using it on anything other than what it was intended for, namely, the P-40 Flying Tiger.

Hope this helps.

Mark,

So it would make sense to conclude that the P-40 stamped cylinder would have only been used (as an identification method) from when they started to make the P-40 until the numbering system was instituted in late 1961. I actually have two P-40 cylinders that have the number 1 stamped over the P-40 stamp, so apparently Cox had leftover P-40 cylinders when the new identification method started being used, and decided to over-stamp the older cylinders.

Regarding the 304-A Cylinder. Do you know if it was sub piston induction?

Thanks, Andy