Bf.109G-2 / G-4

[Big Chudy]

What are the differences between the 109G-2 & 109G-4?

Any help at all is greatly appreciated.

Thank you,
Andrew

[harrison987]

not much...

FuG16Z instead of FuG7a...antenna loop moved further back due to this...660x160 wheels like the regular G6...350x135 tail wheel...

mike

[JoMe]

Hi

Also no spokes on the tail-wheel and an outward bow in the top of the wing (for the broarder wheel).

JoMe

[veltro]

I think that the words of the excellent book of Prien & Rodeike on "The Messerschmitt Bf 109F, G & K series" (quoted here for information and not in disrespect of any copyright law) can be the best description:

"(...)In spite of opinions to the contrary which are expressed now and then, the G‑4 was a development of the G‑2 designed expressly for the fighter role. Compared to the G‑2 the new variant differed only in detail. The FuG VIla radio of the G‑2 was replaced by an FuG 16Z; externally this was recognizable by the position of the fuselage antenna lead‑in, which was moved further aft, and the appropriate insulators on the antenna wire. Like the G‑2, the G‑4 dispensed with the pressurized cockpit, and like the G‑2 there were variations in cockpit ventilation. All told, however, the installation of all four inlets was much more common, although there were G‑4s without any cockpit ventilation openings at all.
Due to the steadily increasing weight of the Bf 109, in late summer 1942 it was decided to increase the size of the aircraft's mainwheels and tailwheel. Accordingly, it was decided to install 660 x 160 mainwheels on the G‑4 instead of the previously used 650 x 150 size.
It is obvious that the first G‑4s received the smaller mainwheels of the G‑2, while conversely the last G‑2s were delivered from the factory with the larger tires of the G‑4. The larger tires continued to be mounted on spoked rims on the G4 and even rare examples of the later G‑6 were to be seen with these. Along with the enlargement of the mainwheels came a change in the angle at which they were mounted. Instead of being almost parallel to the undercarriage leg, the wheel's vertical axis now approached the vertical.
Both changes made necessary the addition of shallow, roughly teardrop‑shaped fairings on the upper wing surface above the wheel wells, necessary to accommodate the upper part of the mainwheels which now projected further from the undercarriage leg when retracted. These were the first such external bulges, which resulted in the name "Beule" (Bump), a name which was to stick with the Bf 109 throughout the rest of its career.
Wings with provision for the larger mainwheels could be ‑ and often were, as referred to above ‑ retrofitted to the G‑2. A 350 x 135 tailwheel replaced the earlier 290 x 110 one.
As the larger tailwheel would not fit into the tailwheel recess, the retraction mechanism was disconnected, although in many cases it was not removed, and the tailwheel was mounted fixed in the down position.
There were individual cases where the tailwheel recess was covered with a metal panel. This modification was also applied to some G‑2s and even to a few F‑Series aircraft.(...)"

Of course inside the book there are dozens of great photographs and examples of the two version, which (togheter with the detailed captions) explain even better the topic...

Hope it helps.