Vivitar 285HV - guide number (did it get a power bump in the last 20 years)?

The manual for one of my Vivitars (printed in 1985) shows the guide numbers at ISO 100 as follow:
1. Super Wide(28mm) - 70(ft)/21(m)
2. Wide (35mm) - 100 / 31
3. Normal (50) - 120 / 37
4. Tele (105) - 140 / 43

B&H site though has it as "Vivitar 285HV Professional Auto Shoe Mount Flash (Guide No.120'/37 m at 35mm)"

So either the guide number really increased in recent years (the difference by my guestimation is about the same as between Canon 430EX and Sigma 500), or there's an error (where?).

From my experience I think mine is closer to the manual, rather then what B&H lists.
On the other hand I've always thought that Vivitar 285 and Sunpak 383 deliver the same power, and given that the Sunpak 383 is listed with the same guide number 120/27 at 35mm - and it has no zoom...might be they both increased in power in the last 20+ years?

I don't have the captioned flash. But there's a review by PopPhoto here if you are interested to read.

There's a mentioning in the second page of the review about the guide number in the spec and as tested.

Personally, I think this flash is very interesting given its price and heritage.

Adorama site lists it at 120' at 50mm.

Likely a B&H misprint.

Redbird_xo wrote in post #3175474
I don't have the captioned flash. But there's a review by PopPhoto here if you are interested to read.

A quote from the above article:

That's exactly what I don't get - these flashes always get compared to 580EX (how is 140 similar to 191?) or SB800 or Sigma 500 , while in fact their power is exactly as 430EX and alike?!?

Kilikanzer wrote in post #3178203
That's exactly what I don't get - these flashes always get compared to 580EX (how is 140 similar to 191?) or SB800 or Sigma 500 , while in fact their power is exactly as 430EX and alike?!?

It begins to look a lot more similar at wider angles. The 580EX GN is 118' at 35mm and 137' at 50mm. And 191' is less than a stop more than 140'.

I think they can be logically classified in the same category of power when compared to some wimpy units, like the 220EX.

Curtis N wrote in post #3178650
It begins to look a lot more similar at wider angles. The 580EX GN is 118' at 35mm and 137' at 50mm. And 191' is less than a stop more than 140'.

I think they can be logically classified in the same category of power when compared to some wimpy units, like the 220EX.

True.
Still - why compare it to 580EX at all, when there's a closer match with the 430EX? ...And yet I rarely hear people saying that 430EX and 580EX have "about the same power"...