Is it possible to have a wiener so large...

…that when a male has an erection, so much blood is directed to the engorged member that the male passes out due to lack of oxygen to the brain?

Side question: if a man dies while having an erection, does the erection stay or does it immediately wither away?

Ask your doctor if your heart is healthy enough for sexual activity.

Just say no to viagra:D

Look up Jonah Falcon.

I get a little light headed, but that’s about it.

No.

What he said. The human body likely has fail-safes of some sort, keeping blood out of the penis, to avoid other, non-optimal results – death, unconsciousness, etc. Citation: the famous porn star Seka is quoted that sex with John Holmes wasn’t that great, his penis wasn’t as turgid as others, it was more like a giant slug moving in and out, in her experience.

You can lose a pint of blood and still be pretty functional. Donating blood they make sure you have drink enough fluids to make up the volume to avoid fainting, but you don’t fall over if you don’t. As noted above, the body has a range of failsafes, and will reach a point where it will shut down almost everything it can to preserve supply to the brain. Fainting is mostly a matter of pressure maintaining flow. After a blood donation your blood’s ability to transport oxygen is depleted by over 10%, but once the volume is made up the pressure and thus flow is fine.

There is no doubt that higher level male cerebral functions are seriously compromised in the presence of an erection, but there is no evidence that the size has any bearing on this observation.

Now we know where the Donkey in your username comes from…

I suspect that mutation would be negatively selected.

Beaten to the punch…line.

Once upon a time, I did the measurement, and my penis (of a not extraordinary size) takes about 6 ounces of blood to get erect. It’s not outside the bounds of plausibility that a penis might take three times that volume, and it’s also not completely unheard-of for a person to faint while donating blood. So by a purely volumetric consideration, it could happen.

But I suspect that the real answer is that, as others have said, unusually-endowed men just don’t get erect enough, because failsafes in the body kick in first.

I love that you did the measurement.

I wonder if they could fashion a little G-Force Flight Condom for your weiner that would allow you to have sex at up to 9 Gs without passing out.

They could call it “Cockpit” or “Joystick” brand.

But how was it done?

Comparison of both states using fluid displacement and a measuring cup, I imagine. I hope the water was tepid.

Yes. Cold water would have definitely affected the data.

What’s the difference between a “grower” rather than “shower”? (in water displacement)

OP may wish to consult the canonical list of big dick jokes. I don’t remember seeing anything regarding blood loss to the brain, but I haven’t been by in awhile.